The Delivery

"Delivery" is the curling term for throwing a curling rock. Many will agree that throwing the rock properly is the most important aspect of curling. No amount of sweeping, brilliant strategy, fitness or mental toughness can overcome a poor delivery. This section provides a step by step guide to throwing the rock properly and consistently.

The delivery, as described in this section, is a compilation of interrelated steps and processes that allow the curler to reach their highest potential. It is the next generation of the time-tested balanced, flat-footed delivery and is the result of years of researching the skills used at the highest level. A straight delivery (balance) with consistent weight control (tempo and timing) is described in this section.

At first glance, it looks no different than most other balanced, flat-footed deliveries. Only after breaking down the parts can you fully realize the difference (and the value).

The Delivery Simplified 

The curling delivery can get very complicated with many moving parts.  Before we dig into the complexities, consider the following overriding principles.

The Big Three

CurlTech has identified the three most important things necessary for a proper, repeatable delivery.  These three principles will apply at all levels of curling.

1. Balance - To throw the rock in a straight line toward the skip's broom.

2. Tempo - To add momentum and gravity to generate energy for repeatable weight control. 

3. Release - To rotate the rock with all energy moving straight and forward with no lateral movement.


Where does the delivery energy come from?

Ideally, the energy to throw all shots comes from three sources.  How each source contributes to the total delivery power is called the Power Ratio:

This ratio allows delivery power to come from the entire body and does not isolate specific muscles. By using this ratio, you will achieve a sustained, efficient, and repeatable delivery.

These three things make up the foundation of the delivery and will be stressed in many different sections. Several things make the CurlTech delivery different from other deliveries. The first is the use of large AND small muscles to throw the rock. Most other delivery methods stress the large muscles of the legs as the key power generator. The delivery skills taught here, when done properly, will become seamless. Nothing about the delivery is stepped or broken. This is critical for the development of the body's kinesthetic sense of motion (kinesthetic sense of motion refers to the body's interpretation of relative movement through a variety of sensory inputs) needed for judging draw weight and achieving overall rock control. The delivery is smooth and seamless. The CurlTech delivery avoids short twitch movements which are also susceptible to stress, fatigue and anxiety.

Since the delivery method discussed here incorporates many muscles working in unison, no one muscle is dominant. Consistency and weight judgment are improved. Also, in tense situations, this delivery is less susceptible to nervousness and stress because many body parts are incorporated.

A delivery, with these principles, can be used by the novice curler as well as the Olympian. It is designed for ease of use AND maximum performance.

The remainder of this section describes these three main principles in detail.

Delivery At A Glance

If you are a new curler, read this section before your Learn to Curl Session. All of these things will be covered in the session.

You will be throwing the rock using a 1-2-3 cadence, a simplified version of the delivery. When it is your turn to throw, follow this delivery process:


In addition, with practice:

Keep reading the other delivery sections for more details.

Delivery Mechanics - How to Properly Throw a Curling Rock 

The delivery mechanics for throwing a rock can be broken down into five total steps.  Always keep Balance, Tempo and Release in mind as the three main delivery principles.  Below are the five steps to the curling delivery:

Let's break things down even further. The following is a detailed description of how the delivery works.

Line of Delivery

Before we get into the steps of the delivery, let's take a moment to understand a key curling term, the Line of Delivery.  The line of delivery is defined as the imaginary line between the skip's broom and the rock's starting point. The line runs through the center of the rock. The skip and the thrower establish the start and end of this imaginary line. When the skip puts the broom down, one end of the line is established. The line is complete when the thrower establishes the starting point, which is normally the same for any one player's shots.

Setup
The "Setup" refers to the body position in the hack as you begin the delivery process. It is the starting point of the delivery. Begin this process as your opponent's rock is traveling down the ice. When your skip is ready to call the shot, you'll be ready. Use the following guidelines for a proper setup.

Setup Option
If the squatting setup position is uncomfortable, there is a setup option. Position the feet as described earlier, bend the knees slightly and grip the rock. You are now in the hips-up position without squatting.  Although you lose a bit of natural body movement, this option is perfectly acceptable.

Clean the Rock - Flip the rock and clean the running surface. With the rock still inverted, clean the ice under the rock with your broom then replace the rock in position. You will see the running edge which is a 5-8 mm circular band about five inches in diameter. Make sure this running edge is clean. Do this to the side of the slide path to keep debris away from the sliding area.

Place your sliding foot flat on the ice, slightly ahead and to the left of the hack foot (heel to toe). There should be less than an inch between the toe of the hack foot and the heel of   the sliding foot.

Point the knee of your hack leg directly at the skip's broom. The shoulders and hips must also be square to the broom at this point.

Holding the broom with the pad facing up, place the head of the broom just ahead of your sliding foot. The broom handle should be gripped about 12-18" from the brush head. The grip point depends on the length of your arm and body. It should be in a position to comfortably hold the broom with the head in the correct position with the left arm slightly flexed. It is important to keep the head of the broom clearly ahead of your sliding foot throughout the delivery. Allowing the broom head to fade back in the delivery may move your left shoulder back and out of square. If you throw with a sliding device, place your hand on top of the device with a soft grip. Make sure your left hand is even with your right hand to ensure shoulder alignment.

Position the rock directly under your throwing shoulder. For most people, this is just to the right side of your hack foot (other starting points are discussed later in this section). The imaginary line between the rock's starting point and the skip's broom is known as the line of delivery (also discussed later). Your throwing arm must have a small degree of flex at the elbow at setup.

Grip the rock - Place your fingers under the handle until your middle finger is positioned in the center of the rock (directly over the center axis of the rock). Hold the handle with the first set of pads on the fingers (closest to your palm). Your palm, however, should never touch the handle. Bring your thumb across the handle to the other side and place it near, but not touching the tip of your index finger .Keep the wrist high without feeling awkward. Your hand should remain in this position throughout the delivery. Cock the handle in the opposite direction of the intended turn. The handle is cocked to the left for in-turns and to the right for out-turns. The position should be at a 45-degree angle for both turns (opposite sides of course). Keep this angle throughout the delivery until you are ready to release the rock.

The Forward Press (#1 in the 1-2-3 cadence)
Once you are comfortable in the setup position, the skip has called the shot, and the sweepers are ready, the fluid motion of the delivery (and the proper tempo) begins. Start by moving the rock slightly forward approximately 2 - 4 inches. This press is the beginning of your body's kinesthetic sense of motion and is the first step in establishing proper tempo and body movement in the delivery, which again is critical to proper weight judgment. Remember to maintain the grip and 45-degree angle described earlier.

As the rock is pressed forward, your lower body should remain still. Move only at the waist and keep both arms slightly flexed at the elbow. Your knee may drop slightly but try to avoid pressing forward with just your arm. This will take your shoulders out of square before you begin the delivery.

Some instructors are teaching the delivery with no forward press. DO NOT eliminate this step. It is essential for proper tempo and weight control.

Press Option - The Rolling Press
The next step is the draw back. It requires you to lift your hips AS you draw the rock back. This can be difficult. If you are not comfortable lifting your hips as you draw back consider the setup option where the hips are already raised. As you press the rock forward, roll your weight onto the handle and let your delivery arm assist you in lifting the hips. When you are at the top of the press the hips already be up. Now draw and step per the next section.

The Drawback and Step - Rock then foot (#2 in the 1-2-3 cadence)
This part of the delivery is one of the most important. Generating power with the body mass and tempo with the rhythm, is critical to controlling the rock. Power generation starts with the draw back as the hips are slightly elevated and shifted back. This positions the hips slightly up and definitely back which enables your body to shift forward and drop into position in the next step. The remaining power will be generated from leg drive and the arm extension, discussed later. During the draw/step, think of drawing-in energy while your hips come up and back, then directing the energy forward toward the skip's broom as you move forward.

The Foot Delay

Ideally, your sliding foot will delay twice.

Here's how the drawback works. Begin by drawing the rock back. Immediately after the rock starts back, lift your hips up (slightly) and back. Leave your sliding foot in place for a moment (the first delay). Then, as your hips are approaching top-dead-center, take a step back onto your sliding foot. When done properly, the sliding foot moves from the setup position to the step position rather quickly. The step is the #2 position.

The term "step" refers to putting pressure on the sliding foot at its farthest back position (heel to toe).From the setup position, simply move the sliding foot back into position and put your body weight on it. This requires lifting your hips and upper body with your hack leg. The sliding foot should now be about 12 inches behind its setup position. Your throwing arm will almost be straight. At this point, your hips should be back (anywhere from directly over the hack to well behind it, depending on the shot, your skill level and ice conditions) and one to two feet higher than the setup position with a slight bend at the knee. Your weight has shifted to the sliding foot with the foot about two to four inches behind the hack. It is very important that the sliding foot is directly behind the position it started in, straight back from setup.If your weight is not on the sliding foot at this point, you have not shifted your weight properly, giving up critical delivery power and control. Remember, to be perfectly fluid, step back only after you have begun the drawback and elevation. This allows the step to be quicker, adding tempo to the delivery.

Think of this motion as an opportunity to create a pendulum action with your hips. Many will argue that consistent draw weight was achieved through the pendulum motion of the old back swing delivery. We agree to some extent and think that the hips up and back position is very similar to the backswing motion. To maintain the proper tempo in the delivery don't shift your weight back any farther after you've stepped onto the sliding foot. This interrupts the pendulum-like motion by creating a flat movement back. It also disrupts the tempo of the delivery.

The Second Foot Delay
The second delay is the most overlooked part of the delivery. The second delay of the sliding foot allows the upper body to drop into place and provide added power to the delivery. Once your hips are up and back, begin moving the rock forward toward the skip's broom without moving your sliding foot (delay). Your body will follow the rock (except for the sliding foot). This puts the rock in front of your body keeping it on the line-of -delivery. Leave your sliding foot behind the hack until the rock is 2-3 feet in front of the hack, halfway to the back line. As your body moves forward over the hack and then over the ice, quickly bring your sliding foot to a position under the center of your upper body. Your sliding foot heel will raise slightly to allow the foot to stay back while the upper body is moving forward. Your foot should catch your body as it drops. Try and wait until the last moment to bring your sliding foot forward and place it in a position on the ice that will allow your body to balance over it.  As a reference, the rock should almost be halfway between the hack and the back line as the sliding foot is crossing the hack. The combination of the fast-sliding foot motion and the weight of your body coming forward and down to the delivery position will generate the power needed. With this combination move, you will generate enough power to throw the wide range of shots with accuracy and consistency. This allows you to generate power using the entire body instead of just the hack leg. Calibrating draw weight is MUCH easier using this method. Be careful not to kick your sliding foot past the center of your body (too far right). The result will be a drift to the right, as your body is not balanced over the sliding foot.

A correct Foot Delay is an athletic move and requires a certain amount of coordinated body movements and leg strength. It requires practice. Start slowly by delaying the sliding just a little bit and work into it.

Managing the Foot Delay
The foot delay can be difficult for some. If you are not comfortable with the mechanics, start by not delaying the foot at all. This may be more comfortable. Slowly try to delay the foot more and more. You can still make all the shots without the delay. Fine tuning your repeatable draw weight and throwing harder weight take-outs will require a delayed foot.

The Slide - (#3 in the 1-2-3 cadence)
Now that you've moved the rock forward and delayed your sliding foot, you're ready to move the body into the sliding position. After the rock is moving, catch your body by quickly moving the sliding foot under the chest. At the same time gently push out of the hack with your leg. The leg drive should perfectly compliment the weight given to the rock by weight shift and body drop. Leg drive is roughly 20% of the total power of the delivery. The body dropping down as a result of the foot delay will generate about 70% of the power with arm extension representing the remaining 10%.Excessive leg drive produces more of a push from the large leg muscles (quadriceps) instead of a fluid throw from the whole body. This is the major difference between the CurlTech delivery and the others.

Pro Tip:  After your weight has transferred back, start moving forward with the rock first - moving it directly toward the skip's broom.

As you slide out, you will now transfer all of your weight from the hack foot to the sliding foot. This is the most difficult part of the curling delivery. Your sliding foot should move in behind the rock with the heel on the line of delivery and behind the center of the rock. Once your sliding foot is in place, the heel should be underneath your sternum. Try to angle your sliding foot out at this point. By rotating the foot counterclockwise (out) you increase the sliding area of the foot. Approximately 30-45 degrees is optimal however, some people cannot turn their foot in this manner. Turning the foot is not delivery critical. It simply helps you balance. It does however help turn your sliding leg out (called an open hip) which helps the body stay square to the broom. Angling the sliding leg in (called a closed hip) may angle your body to the right, making alignment more difficult. After the initial weight transfer, the slide should be established. This should occur at or before the tee line.

Watch the video above. Watch the delivery in full speed. Pay close attention to the two foot delays. One delay as she's drawing the rock back and the other as she's moving the rock forward. Rock, foot, rock foot.

Once your delivery is established, no downward pressure should be on the rock or the broom (sliding device) at this point. As a practical matter though, the broom can be used to help you stay upright if you inadvertently place the sliding foot too far right. It also helps newer curlers not fall while they practice good balance. Perfect balance is great but, as mentioned earlier, the goal is not to put excess pressure on the rock or broom. Your hack foot should trail directly behind your body, on the line of delivery.

Your upper body should be roughly 30-45 to the ice at this time. This position allows good balance and visualization of the entire plane in front of you. A position that is too low will not allow the visualization of the plane while a position too high will not allow good broom alignment and sighting.

Your grip should be soft at this point with the handle still coked at 45 degrees and some bend at the elbow (finesse not strength). NO ROTATIONAL PRESSURE SHOULD BE APPLIED IN EITHER DIRECTION UNTIL RELEASE. Think of the slide as the time to lay the rock down for your sweepers. A nice, smooth slide with no rock movement will keep the rock on the line of delivery.

Your broom head is still clearly ahead of your sliding foot and your shoulders are square. The broom should be resting on the ice with minimal pressure (If one of the sweepers kicked it, your delivery would still be sound).

Sliding Foot Angle

The sliding foot, in a proper delivery, is the platform that allows the body to slide balanced.  If possible, angle the sliding foot outward a few degrees.  Anywhere from 10 degrees to 40 degrees is recommended.  Even a small foot angle increases the platform width and makes it easier to balance.   Avoid turning the foot more than 40 degrees as this is places a strain on the hip.

The Trailing Leg and Foot
Your trailing leg (push off leg) should trail straight behind your body. Keep as much pressure as possible off the trailing leg as it will drag, create friction and cause your delivery to decelerate. The trailing foot should be rolled over with either the top of the foot on the ice or just the toe. Angling the trailing foot can act as a rudder which will rotate the body on its vertical axis (see Axis Analysis later in this section).Keep it as straight as possible. Dragging the knee is not improper but does add significant drag to the delivery. The more pressure that is applied to the ice by the knee, the faster you will decelerate.

The Release
As you slide through the house, your arm should still be slightly flexed, and the handle still cocked. They both should remain this way until just a few feet from the intended release point which, depending on how much power is being generated by the delivery, should be somewhere near the hog line.

All of the rock's rotation is applied within a 4- or 5-foot area by shifting the handle from the cocked position to the twelve o'clock or hand shake position.

At this point all of the energy from the delivery is hopefully moving toward the skip's broom.

When you are four or five feet from the release point, begin rotating your rock and straightening your arm. The flexed arm allows you to throw the rock instead of just letting it go. This is known as a positive release, referring to the solid rotation of the rock and the forward movement of the arm toward the skip's broom. Keep the energy moving forward by applying the release evenly with no lateral movement.

Application of the Handle (rotation) in Detail
In order to keep the rock on the line of delivery, the rock must be rotated over its center point. The pressure that turns the rock comes from only two fingers and the thumb, depending on the turn, one finger on each side of the center point. For an in-turn, the thumb moves to the right and ring finger to the left, counter to each other. Each pressure point is the same distance from the center axis of the rock. For the out-turn, the index finger and ring finger apply the necessary pressure.

Any lateral movement of the rock while putting on the turn will result in the rock moving off the line of delivery. This is where many shots are missed. Extend the arm through the base of the skip's broom. Never raise the arm at release. This will interrupt the fluid forward motion of the release.

How Many Rotations?
For consistency and predictability, the rock should rotate approximately 3 - 5 times during the length of a draw shot. Ice conditions will effect the number of rotations.  This is very important since the number of rotations directing impacts the speed AND curl of the shot. For example, a rock that rotates 1-2 times will stop shorter and curl more than a rock rotated 5 times. In some cases, a lot more. For league play, try to target 3-4 rotations. For competitive team play, each team must agree on the rotations so that the ice measurement and sweeping tools can be consistently applied.  Ice conditions will likely dictate the number of rotations.

For example:

Very straight ice 1-3 rotations.

Straight ice 2-4 rotations.

Swingy ice 3-6 rotations.

Very swingy ice 4-7 rotations.

Consider the following:


Split Time Rotations Distance Curl

3.85 2 Rotations Top Twelve 5.0 Feet

3.85 3-4 Rotations Tee Line 4.0 Feet

3.85 5 Rotations Back Twelve 3.5 Feet

As you can see, the same spilt time can produce three different shots. The Hog to Hog time will also change with different rotations.

There are times when more or less rotations are necessary. Aggressive (or bald) running surfaces, ice that curls over five feet or ice that runs straight. These are advanced concepts and should discussed with your team.

The Follow-Through and Post-Shot Assessment
The follow-through is also a key component of the delivery. It is important to stay in the sliding position for several seconds after letting go of the rock. This will prevent you from popping up too early and will also give you a good look at the shot as it travels down the ice. This is valuable in the assessment process that each player should go through immediately following the shot. To improve balance and build leg strength, hold the balanced delivery position until you stop. Never rest your hand on your sliding foot. This will create a balance dependency in the follow-through and reduce overall balance consistency. Avoid the temptation to follow directly behind the shot. This is a team sport and the other players on your team have control of your rock. After release, consider this the hand-off point to your sweepers and skip.

Watch the rock as it travels down the ice. This will allow you to see the rock's overall path for future reference. The farther away you are the better your overall view of the entire shot. The skip and sweepers should be prepared to handle all sweep calls.

Do not rest your bare hand on the ice for longer than an instant. Your body temperature will melt and damage the ice in a matter of moments. Also, never rest your knee on the ice for longer than a few seconds. Even with pants on, your body temperature will melt and damage the ice.

During the assessment of each rock, determine if you've hit the broom with the proper weight. If it was a good shot, try and remember what it felt like so you can do it again.

If you missed the shot, try and figure out why. Make small adjustments.

The Weight Window 

The responsibility of the person delivering the rock is to throw the proper weight on the proper line (hitting the broom). Because sweeping can add up to 10 feet of distance to a rock (league sweepers are more like 2-3 feet), the thrower only has to hit this weight window. Your weight window is based on the effectiveness of your sweepers and a little on ice conditions.  Depending on the quality of your sweeping, the window ranges from 3 feet at the league level to 10 feet at the elite level.  This means that if a league rock is thrown 2 or 3 feet short of the intended stopping point, the sweepers can increase the distance and place the shot. So, any rock thrown inside the weight window is thrown correctly. For sweepers to effectively manage the rock placement, the ideal weight is in the back half of the weight window. It is then up to the sweepers to complete the shot. If a rock is thrown beyond the intended stopping point, there is nothing the sweepers can do to help. In other words, it's better to be a little light than a little heavy on draw shots.

The weight window ranges from a zero foot window with no sweepers (wheelchair curling) to approximately a ten foot window with two world class sweepers. The perfect window is on the short end of your sweeper's ability. If your sweepers have an eight-foot window, throw the rock on the font end of the window to allow your sweepers to place the rock. A true team shot.

Consider the following:

Club level sweepers at 60 lbs. of pressure. 2-3 foot window.

Competitive level sweepers at 80-120 lbs. 3-6 foot window.

World class sweepers at 140 lbs. and above. 8-12 foot window.

As you can see, good sweeping is a huge advantage.  See the Sweeping Section for tips on adding pressure.  Determining proper weight is difficult to teach because it relies mostly on the body's sense of position and movement. This kinesthetic sense is different with all players. Practice, and the level of fluidity in the delivery will dramatically increase this skill.

Adjusting the Delivery for Different Weights 

One of the most commonly asked question from beginning curlers is, "How do I adjust the delivery for different weights". Several different weights are required to throw all of the shots in curling. In addition, ice conditions are different from club to club. They may even be different within the club, where the conditions are constantly changing. From guards to heavy peels, the CurlTech delivery can accommodate.

The answer to the above question is that all power generators of the delivery need to get stronger for stronger shots. Specifically, the weight shift, body drop (slider foot delay), leg drive and extension.

For example, on heavier shots and heavier ice, the weight shift may change from the hips being over the hack to hips being completely behind the hack. Body Drop may change from a slight delay to a long delay. Leg drive may change from almost nothing to a full push. Arm extension may change from a slow extension to a quick one. Extra power is also needed with small-framed or petite curlers. The body weight/rock weight ratio changes significantly from a 100 lb. frame to a 185 lb. frame. The smaller framed curler must use the extra power to throw all shots. The rock is 42% of the 100 lb. curler's body weight. This is equivalent to the 185 lb. curler throwing a 78-pound rock!

Harnessing the Power 

Changing weight first depends on the body's ability to generate power and ice conditions at the time. Each person has a varying degree of athleticism. This is a big factor when it comes to describing how to adjust weight. Early thinking on the no-lift delivery centered on leg drive. More weight - more leg drive. Less weight - less leg drive. This is not the case. The leg muscles cannot be tuned finely enough for the subtle changes needed, particularly on fast ice.

As a general rule, curlers should generate enough power to slide through the hog line.

Now that we understand the power generators, we must adjust them all when adjusting weight. The following matrix is directional only. Each curler will differ. Use it as a base point and modify if necessary. The first matrix describes how the power generators may work throwing different shots on different ice conditions.

Weight Control Simplified
All players can establish a draw "default weight".  This is the weight that is the most natural and and repeatable.  This default is based on the conditions you normally play in and what type of sweeping you normally play with.

Sweeping Default

Recreational Top eight foot.

Athletic Top 12 foot.

Elite Top 12 foot.

To establish the default, split time your delivery and make adjustments based on conditions.  Below is a guide:

Conditions Split

13.5 seconds 3.60

14.0 seconds 3.75

14.5 seconds 3.90

15.0 seconds 4.10

Many curlers over-think the weight control necessary to make most shots. As it relates to draws, there are an infinite number of places a rock can stop between the hog and the back line. A common question is, "How do I change my weight for all these different shots" .The CurlTech suggestion is to break down all draw shots into three weights. 

Balance, Tempo, and Release

As mentioned in the beginning of this section, there are five major components of the delivery, set up, press, draw/step, slide and release. If you want to perfect your delivery, you will have to add some detail on the key components. There are three enhancements that will perfect the delivery. Focus on the following.

Balance - The Foundation of a Good Delivery 

The term balance in the curling delivery means the body being centered or balanced over the sliding foot. Balance is needed to throw the rock straight and to allow the power and energy to be funneled down the line of delivery (a line AND weight issue).Your athletic ability will dictate to some degree the level of balance that can be achieved. Two important factors should be considered, your spatial skills and proprioception skills.

No matter what your ability, though, balance is still a key component. Some people can balance perfectly on their sliding foot with no pressure on the rock or broom. This is an ideal situation but is not necessary for most curlers to enjoy the game. For most, balance simply means not favoring either side (rock side or broom side) during the delivery. This means your sliding foot is under your body.  A little pressure here and there on the rock or sliding device is not a problem for most club-level curlers. Balance allows the body to slide more upright. The more the body is upright, the straighter the slide becomes without lateral energy to steer you away. A straight slide will produce a straight line of delivery giving the curler a greater chance to hit the broom. Refer to the Line of Delivery Section for more good information.

Balance is the number one building block to throwing the rock on the line of delivery and tempo is the building block for weight judgment. Balance allows you to slide straight and channel energy toward the skip's broom and to throw the rock on the line of delivery without lateral movement (drifting).Focus on balancing over the sliding foot. If possible, put no weight on the rock or broom (sliding device).Without some type of balance, you will never reach your true potential as a shot-maker. Most curlers favor the broom side by leaning on the broom. This puts your body weight off-center and results in a drift to the right with energy being diverted to the right.

To test for proper balance, raise your broom one inch off the ice after your delivery is established (tee line). If you use a sliding device, take the pressure off the handle.

To achieve a balanced delivery, your sliding foot must be in the correct position as you slide. The sliding foot must be under your chest with the heel on the line of delivery.

Finding Your Balanced Foot Position

Not all sliding feet are created equally.  Since  there a differences in body types, so are the foot placements for balance.  Your sliding foot angle can dictate where the foot is placed in relation to the line of delivery.  A severe foot angle of 45 degrees or more will place the heel of the foot on the line of delivery.  A non angled foot (straight) may place the foot slightly left of the line.  To find your position, follow the steps below:

The "Tripod" Affect

All curlers want to feel stable and safe as they deliver the rock.  Because balance is difficult (all weight over your sliding foot), newer curlers add tripod-type stability to feel stable and safe.  The three points of the delivery tripod are:

Notice that the rock itself is not part of the tripod since, at some point you must release it.  The most common tripod configuration is the sliding foot to the right of the line of delivery.  This forces a slight "lean" to the left that can be comfortably controlled by leaning on the broom or device. This is very stable.  However the result is lateral energy to the right that takes your delivery off line.

Learn with a Sliding Device
Every beginning curler should learn to deliver with a sliding device. The Sliding Device gives you left-side stability while you learn to slide (balanced) over your sliding foot. Unless you're a top athlete, it's unreasonable to expect you to balance over the sliding foot right away. Some people never feel comfortable sliding balanced. If and when you are comfortable sliding balanced, switch to throwing with your broom. Switching to a broom too early will lead to other delivery issues. While using the sliding device, work on your balance by focusing on your sliding foot directly under your chest. As you slide out, test for balance by taking weight off of the sliding device. DON'T LIFT THE DEVICE OFF THE ICE. Try holding the device with a very light grip, just in your fingers.

Tempo 

Tempo is a musical term that we can apply to the curling delivery. In our case tempo is the pace and rhythm of the delivery. More specifically, it's the fluid pace and rhythm of the delivery. Later in this section we will talk about how tempo is incorporated into the three main steps of the delivery. A delivery with tempo helps the body control power and energy. Many other sports use tempo in the mechanics of the athletic move. A  baseball pitcher using the windup. Every golf swing, every bowler, every baseball hitter. Removing rhythm and tempo from the delivery removes the ability to naturally control the body movement essential for weight control. The timing and the flow of the moving parts will also help the fluidness of the motion.

Tempo keeps your body in motion, which is good. Perfect tempo can be measured by the old one-one thousand, two-one thousand, three.

Release 

The above section described the release mechanics. Release is one of the big three because you must keep the rock on the line of delivery by keeping the energy moving forward. Any lateral movement or sharp forward movement (jab) at release will make your shot making inconsistent.

More on the Power Ratio

Let's talk more about how power is generated during the delivery. There are misconceptions here. There are three key power generators in the delivery. They must exist each time you throw a rock:

Followed by, to a lesser degree:

The Sliding Foot Delay
The Foot Delay by CurlTech, is also a key delivery component. If done properly, it is seamless.  The Foot Delay refers to the sliding foot being delayed two times in the delivery. Once as the rock is drawn back and another as the body moves forward to slide. The second delay allows the body to drop slightly down and forward. This allows gravity to help generate power. It is covered in detail later in this section.

Delivery Equipment

The Sliding Device


The rules permit a player to deliver a rock with a broom, without a broom or with a sliding device. The use of a sliding device began in the late 1990's.Devices such as the Crutch or Stabilizer can be used by any curler to help achieve a more upright, balanced-like delivery.

ALL new curlers should learn with a sliding device. As you begin to feel more comfortable over your sliding foot, transition to your broom for sliding purposes. Your goal is a neutral left side.  Using a device to assist if needed. It shouldn't matter what is in your left hand.  Transitioning to a broom helps eliminate one piece of equipment. Proficient adult curlers can expect to transition to a broom from the sliding device after curling for one or two years. If balance is difficult (or impossible) to achieve, we recommend the permanent use of a sliding device. This allows you to place a little weight on the broom side of the body. As mentioned earlier, the more weight you put on the broom or sliding device, the more your body will be out of square and a drift to the right will occur. If you need the device for any reason, try to apply as little pressure as possible.

Caution!!
Don't allow the ease-of-use of the sliding device to prevent you from achieving a more balanced delivery. We've seen capable curlers never achieve a good balanced delivery (causing line of delivery and weight problems) because of the sliding device. It's very easy to simply lean on the device and feel comfortable.

The sliding device can also cause some logistics problems with your team. After delivery, the device must be placed at the opposite end of the sheet in preparation for the next end. Front-end players (lead and second) are not allowed outside the hog lines during the end unless they are throwing, sweeping or preparing to sweep. Moving though the house area with your sliding device is a violation of the rules and may be distracting to your opponent. Using a team sliding device (everyone slides with the same device) is a better option. Each player simply hands off the device to the next player. You may even have two, one at each end.

Sliders

You learn to slide with a step-on slider.  This is perfect.  After you have played a few games consider buying curling shoes.  Any curling-specific shoe will provide more stability in the slide and allow you to achieve a more balanced delivery.


The sliders that are built into curling shoes are faster and more stable than the slip-on sliders used by newer curlers. Stability is necessary for good balance. As soon as possible, invest in a good pair of curling shoes for improved stability and balance. The best shoes for stability are ones with a thick Teflon slider on a shoe with a good, stable, high-grade leather upper. Shoes with a full, thick slider on the whole surface are more stable.

CurlTech Choice for shoes:

Teflon sliders come in two types, the full and the pad type. Pad types have two pieces of material, one on the heel and one on the front foot. These sliders are more comfortable to walk in since they hinge in the middle. Full sliders are more stable. This is why we recommend them.

Delivery Troubleshooting

CurlTech receives many requests to analyze individual deliveries. Visit the "Analyze My Delivery" page for individual analysis. Our first response to curlers would be to ask the following questions:

If a curler can answer yes to all questions, no changes are necessary, even if the delivery is not proper. A proper delivery simply helps the curler be consistent with line and weight. Of course many curlers answer no to at least two of the questions. This is where delivery analysis and troubleshooting comes into play.

Common Line-Related Problems 

The following examples are the most common things we see in clinics at all levels.

Sliding Foot Placement
The number one problem we see with beginning and intermediate curlers (and even some advanced) is the improper placement of the sliding foot during the slide. In most cases, the foot is over-placed, meaning the foot is too far right and not under the chest (see the tripod affect earlier in the section). This results in an out of balance delivery drifting to the right.  The drift is caused by the momentum of the sliding foot and leg moving from left to right.  Correct this by placing the sliding foot farther left and on the line of delivery.  Make small adjustments to the left until balanced.

Right-Side Vulnerability
Most people require a little assistance with balance. Leaning on the broom or sliding device is the most common type of support. It is easy to let the broom or device help keep you stable. Stability is not the same as balance. Since the broom or device is on the left side, pressure can be applied. There is no such option on the right side so people tend to over place the foot creating a tripod with the sliding foot, trailing foot and broom. The tripod causes the over-placed sliding foot slide and lateral energy to the right is created. Correct this by practicing balance (see the Skills and Drills page).

Improper Alignment and Sighting

Even with the sliding foot in balanced position, the the thrower must still throw at the skip's broom.  Misalignment in the hack may cause the rock to start (and possibly stay) off the line of delivery.  Improper sighting of the skip's broom and line is also a problem.  Few curlers can perfectly sight the rock down the line, mainly because the line of delivery is outside their sight line.  Feedback from the skip or coach will allow the thrower to "feel" what the line looks like.

Pro Coach Tip:  Determine why the thrower is "off the broom" before you fix any mechanics.

Lateral Release Energy
Even with good balanced and sighting, shots can still be missed at release. All release energy must be straight down the line of delivery. Any lateral (inward or outward) energy will put the rock off-line (or change the profile of the curl). Correct this by holding the 45 degree angle and rotate to the hand shake position.  Rotate the handle over the center of the rock and finish forward and not to either side.  Avoid release that a quick (jab) and all back-handle releases as they will almost always apply lateral energy at release.

The Wide Trifecta
Balance problems are more noticeable on outturns thrown on the right side of the sheet. We call this the wide trifecta of delivery problems since there are three delivery issues at work.

It gets worse... Not only is your shot wide but the two (the first is just a visual problem) sources of lateral energy are effecting the curl profile, lengthening the free run. The trifecta is the source of many complaints about the ice being straight in this area.

If your outturns are consistently wide and straight on the right side of the sheet, don't blame the ice tech until you fix your delivery.

Common Weight-Related Problems - Power Ratio

Improper or No Weight Shift
Consistent weight control requires the entire body working in unison. Shifting your weight from the hack foot Press (1) to your sliding foot during the drawback and Step (2) moves your hips back and slightly up. Without the weight shift, power and control are lost. Correct this by consciously placing weight on the sliding foot in the Step position.  You are now ready for the forward movement in the delivery.

Lack of Tempo
Consistent draw weight requires a fluid motion with rhythm. One-one-thousand (1), two-one-thousand (2), three (3). These steps must have an even rhythm without pause.

Lack of Sliding Foot Delay
Delaying the sliding foot from the Step (2) position to the Slide (3) position is necessary for fluid power and to create the proper Power Ratio". The foot delay allows the body to drop into place to help calibrate weight. A lack of delay causes the power to come from the hack leg or push off.

Extra Power added at Release
A noticeable push or jab at release can add several feet of distance to a draw.  Only a small portion of the weight is created at release. The arm and hand represent small muscle adjustments to weight.  Correct this by managing the Power Ratio.  This is difficult without a trained analyst.

Common Line/Weight Combination Problems

Rock Rotation
The number of rock rotations  can change the line AND weight of a delivered rock.  We suggest 3 rotations on straight ice and 4-5 rotations on ice that curls.  Over-rotating will add distance and less curl while under-rotating will add curl and less distance.

Delivery Quick Reference

Setup

Forward Press

Drawback/Step

Move Forward and Delay the Foot

Slide

Release

Follow-Through

Advanced Delivery Skills

The CurlTech gets many requests in the advanced delivery category. There are only a few true advanced concepts when it comes to throwing the rock. The advanced player may be seeking a higher level of competition which requires mastering the skills. Advanced skills should only be used after you are proficient in the fundamental skills. Test yourself and your readiness for advanced skills by answering the following questions:

By answering the questions, you can gauge your readiness. If you answered no to any of the questions, more work is need on the basics.

What to expect in this section:

Mastering the Skills 

Many curlers come to the CurlTech asking for advanced delivery tips. Most of these curlers are looking for a quick fix to some fundamental problems. These curlers are often told to refocus on the basic delivery skills. We direct them to the certain delivery components that can be changed for better performance.

First and foremost, there are three things (Remember the Big 3) that when mastered, will allow you to achieve at ANY level. They are:

All delivery components are designed to achieve the above. Mastering the delivery critical components of the delivery must be done first.

To master draw weight, add Foot Delay and Tempo

To master Line of Delivery stay Balanced with a proper Release.

Master the above delivery components and you have a delivery shared only by players at the highest level. Only after mastering the above skills can you fully benefit from advanced skills.

Here are some tips on mastering the fundamentals:

If there's one thing that rises to the top of the list, it's balance. Balance is the main building block of the delivery, particularly when it comes to throwing the rock straight. Weight shift and body drop with tempo are necessary for draw weight consistency. A proper release with no lateral movement if necessary to complete the delivery on the LOD. Tempo is an added feature that helps you gain consistency.

Balance First 

The term balance comes up a lot in this manual. To the advanced curler, balance is still fundamental. Of course having perfect balance does not guarantee the other components are correct. Once balance is achieved, the other key areas such as tempo, proper step and drop and release can be achieved. Good balance is helped by the two following skills:

Spatial skills help your judge how stable you are, how fast you are moving and how fast you are converging (to the other end of the ice).Both are essential for good weight control. Proprioception skills help with placing your sliding foot in the same spot every time. Both of these skills can be developed.

In addition to the obvious line of delivery issues associated with a straight delivery, there is also a subtle weight component. A balanced delivery moves straight down the line of delivery. This means that all of the energy in the delivery is concentrated toward the skip's broom.

An out of balance delivery that leans on the broom drifts to the right. As the delivery drifts, a portion of the delivery energy is diverted laterally, from forward to sideways. This may not seem like much but on 14-15 second ice it could be the difference between the button and the top eight-foot. As energy is diverted laterally, some compensation must be made.This leads to inconsistency with weight. In a perfectly balanced delivery, 100% of the energy is down the line. Diverting the energy sideways may pull 5-10% of the energy to the side and it is very difficult to calibrate draw weight every time.

The advanced curler owns balance. To a top-level player, balance is not an occasional thing or something that must be thought of on every shot. Balance must become instinct to achieve a high level of success.

Balance Factors
Different players have different levels of natural balance ability. The following are a few examples of things that effect balance:

Good news...You can practice and get better at some of these. Strength and flexibility can be increased by working out properly and maybe doing some yoga. Contact your local trainer to help with this. Proprioception skills can be practiced. Try this quick measurement test. In the warm room, balance on just your sliding foot for as long as you can. This will help your body feel what it's like to slide over that foot. Now close your eyes .If you tip over within a few seconds, you need to practice. Athletes that have good proprioception skills can balance on one foot with their eyes closed for 15 seconds or longer.

Based on the above factors, one player may be able to slide balanced each and every time with little practice or effort. On the other hand, some curlers must work constantly on their balance to ensure an instinctual balance situation in games. A few will always struggle. Read the Practice Section to learn about how you change instinct.

Shoes

Shoes can help performance.  Any shoe with a thick slider and firm support can assist you in your balance efforts.

The Sliding Device
As mentioned earlier, we recommend the use of a sliding device for any curler who is unable to balance properly. Take this test. Take a practice slide out of the hack with no broom. If you can do it (even if it's wobbly), you can slide balanced. If you can't (either you fall or your sliding foot is completely out of control) you should be using a sliding device. This is called the gun to head method of testing for skills. If forced to throw balanced, can you? Most people lean on the broom or sliding device because it's easy, not because they have to. If it is not possible to throw balanced, use a sliding device. It also helps keep the shoulders upright and square to the broom.

Adding Tempo to the Delivery 

To gain weight consistency in your delivery and shot making, add tempo to the delivery. Tempo refers to the rate and rhythm of the press, draw/step and slide. In golf, instructors teach tempo to regulate the swing as not to swing too fast or slow. The same logic applies to curling. To gain the most consistency in the delivery, a constant rate and rhythm must be incorporated. It's as simple as slowly counting to three (one, one thousand - two, one thousand - three).The human body is profoundly rhythmic and your kinesthetic sense of movement is enhanced by adding rhythm and movement to the delivery. Taking the rhythm (tempo) out of the delivery and becoming more static, or movement free, will take away performance and draw weight consistency.

In the 1990's some curling professionals argued there is too much movement in the delivery. These professionals taught a delivery with very little movement other than a push out of the hack. This was a mistake and CurlTech never taught this method. Today, we see less and less of the old static delivery.

Tempo Detail
Use the following to master tempo. Adopt the 1-2-3 cadence.

Tempo allows all body parts to work together fluidly. Any delay or quickening of the count disturbs the rhythm (and performance).

Tips on Tempo
As you progress with your tempo, one more modification is necessary. To allow the entire body to throw the rock (one of the key principles of the CurlTech delivery), add a slight delay between drawing the rock back and drawing the sliding foot back. This is the most difficult part of adding proper tempo. The sliding foot must delay slightly before moving to the step position. In the overall process of the delivery, think about this as a double delay. This means the sliding foot delays twice during the delivery. Delay the foot as you start to draw back and delay it again after forward movement. Think about the sliding heel kicking in behind the rock (rock moves out first) and never moving simultaneously with it.  This is a subtle modification. It is also a truly advanced delivery characteristic. When done properly, the sliding foot moves under the body quickly, allowing the body to drop in place. If the sliding foot does not delay, a push delivery is the result, dramatically reduces your draw weight calibration (and power).

The sequence looks like this:

Advanced Release 

As mentioned above, the proper release will have a positive component. This can mean two things:

Positive Forward Movement
This means the rock will moves away from the body at release. This is proper because it helps the bodies kinesthetic sense of movement and helps calibrate draw weight. There two types, extension and rotation.

Positive Rock and Handle Rotation
Positive rotation refers to extra rotation which may be necessary to adjust for conditions like a bigger than normal curl or ice degradation (fudging).

Positive Lateral Energy
Be careful here. There are very few situations that require setting it out at release. Discuss this with your team if you think this is something that will help you. In most cases, a straight line of delivery with 3-4 rotations will work.

Rock Rotation
Earlier we talked about the best number of rotations for your league and social curling. Approximately 3 - 4 rotations is a good average. It's worth talking more about how the rotation impacts the speed and curl. For competitive team play, each team must agree on the rotations so that the ice measurement and sweeping tools can be consistently applied.

If all of the different rotations stop on the tee line then the HTH times will change. The HTH times get longer with more rotation. There are times when more or less rotations are necessary. Aggressive (or bald) running surfaces, ice that curls over five feet or ice that runs straight. As your team discusses these issues, it's important to keep the rock energy in mind. Whatever you decide as the team rotation, no lateral energy can be applied. If conditions dictate, and you decide to move the extremes. Practice applying the rotation without lateral movement.


More on Line of Delivery 


Line of Delivery Defined
The term line of delivery has been used many times so far in this section. Line of delivery is defined as the imaginary line between the skip's broom and the rock's starting point. The skip and the thrower establish this imaginary line. When the skip puts the broom down, one end of the line is established. The line is complete when the thrower establishes the starting point, which is normally the same on all shots. This line is fixed once it has been established. Obviously, the skip's broom position will likely change each shot. On the other hand, the throwers starting point should be the same each time.


The big question - Where should you start the rock?

Line of Delivery Options
The answer to this seemingly simple question is still being debated among the curling instructional community. Instead of providing the answer, we'll provide the options and let you decide what works for you.


Option #1 (preferred) Directly under your throwing shoulder

Option #2 The center of the hacks (between the hacks)

Option #3 Your hack toe


Option #2 was used almost exclusively when the rock was thrown with a back swing. We had no choice. Now that the back swing is a thing of the past (at least as far as instruction goes) we have three options.
Option #1 is the most comfortable and allows you to throw the rock by extending the arm in a straight-forward manner. This is preferable . It is also the easiest method. The ease comes at a cost however. Because the rock starts left of the center line, the geometry of the line of delivery changes as it relates to the sheet geometry. F or example, when the skip's broom is on the centerline, the line of delivery runs down the left side of center.
Option #2 offers the most consistency if you play on a team with right-handers and left-handers .It is a more conventional starting point because it utilizes the line of delivery we've used for many years. This option is rarely used today. However it does provide:

Option #3 is not recommended because it dramatically changes the line of delivery geometry from one side of the centerline to the other. Rocks thrown on this angle travel down the inside of the center line. It also forces you to throw from your chest (like throwing a Frisbee) increasing the chances of lateral movement in your release.


Field of Play and Line of Delivery

As mentioned earlier in this section, the rock can be drawn back to several different points. Since the rock's draw back point is the starting point of the line of delivery, the LOD changes for each drawback location. The rock can start the LOD anywhere from the center line to the front of the toe. When the rock starts at the centerline all shots are centered in the field of play. This means all shots start in the center of the sheet. As you move the drawback point farther left (righties), shots start at a point left of the center of the sheet. Why is this important? It may or may not be depending on the quality of the ice. The ice technician prepares the ice parallel to the side and center lines. When the ice is scraped, the machine moves parallel to the side and center lines. The refrigeration pipes under the ice, in most cases, are also parallel to the side and center. This may cause rocks to run along the scrape and pipe lines. This is irrelevant if the rock is drawn to the center. Rocks draw left of center will either have to have to cross over the pipe and scrape lines or stay parallel with them.


Hitting the Broom

Hitting the broom refers to accurately throwing the rock down the intended line of delivery. It is very difficult to sight the rock from the delivery position. Most curlers can never truly sight the broom since the dominant eye is rarely on the line of delivery. Since the rock is always slightly to the right of the body center (a little farther right than the right eye) it is very difficult for the shooter to accurately sight their shots. As a thrower, try to accept the skip's feedback as to whether or not you hit the broom. The skip is the only player to have true sighting ability of the rock. This probably leads to the cause of skip/player disputes regarding hitting broom.


Shooter: "Why did I miss that shot?"
Skip: "You were wide"
Shooter: "No I wasn't"
We encourage players to feel what it's like to hit the broom. 


The Release and the Hog Line

The current WCF rules states that the rock must be clearly released by the hand before it touches the hog line. In championship play, the hog line rule has been contentious for many years. This rule does not favor the athlete. It essentially says that if the Hog Line Judge can't tell, it's a violation. Canada and the United States play slightly different rules. In the US, the rock must be clearly touching the hog line before it's a violation. This favors the athletes and is much easier to call from a Judges perspective.
Repeated video analysis of players releasing the rock near the hog line suggest that the hand really is quicker than the eye. Testing showed that a rock pulled by a hog line judge was released properly 75% of the time. The hog line judges were not incorrect since the rule favored them. A better system was needed.


Sensor Handles
In world play (and in most national play) there are no human Hog Line Judges. They have been replaced by technology. Sensor handles are used to determine violations. The handle measures conductivity when the hand is placed on it and has indicator lights that will either shine green or red. If the handle senses conductivity from your hand when the leading edge of the rock touches the hog line, the lights shine red indicating a violation. A clean release will activate the green light. If red is flashing, it's a violation and the rock is to be removed from play.


The handles work in combination with a magnetic strip just below the ice surface. It is important these strips are placed in the correct spot. Before each shot, the internal mechanism of the handle must be activated to allow conductivity to be measured. This is done by flipping the rock upside down during the cleaning process.IN ORDER TO PROPERLY ACTIVATE THE HANDLE, THE HAND MUST BE ON THE HANDLE AS YOU FLIP IT.A handle that is not properly activated will not sense your hand and will act as a dead or inactive handle. An inactive handle can be thrown over the hog line with no red light. Of course players are already figuring this out. Check your opponent's rock as it travels. A clean release will shine green for about half the sheet. If no light shines, it's inactive. Expect a new rule from the WCF that requires proper activation prior to each shot.


How many hog line violations can your team afford? The answer is none. This was brought to our attention by a former world champion that claimed he never had a hog line violation in his 40 years of curling. His point was to train yourself to release a foot before the line. 

Other Advanced Topics

The Curl Profile

The curl profile is the shape of the rock's curl and its path. After release, rocks will stay on the current path (hopefully the line of delivery) for a period of time. Most rocks run straight at or near the skip's broom for a certain amount of time until the forces under the rock will make it curl. See Why Rocks Curl in the Field of Play Section for more information. The rock curl profile has five components:

Slide
During the slide, the rock is the hand of the shooter. The friction under the rock has no effect on the rock because the hand won't allow the rock to begin curling (or decelerating) and there is no rotation. In rare cases, an aggressive running surface and ice condition can cause the rock to curl while still in the hand. A light grip may be susceptible to this.

Release
Once the rock is released, friction makes the rock decelerate immediately. Differential frictional melting begins (or leading edge scratching) and the rocks can start curling. At release point, the turn is applied. By quickening or shortening the release, the shooter has the opportunity to lengthen or shorten the free run respectively. 

Free Run
The free run is the portion of the shot after release where the rock begins to decelerate but has not started to curl yet. On straight ice, 1-3 feet on draws, the rock can run free for 20-30 feet before noticeably curling. On swingy ice, 4-6 feet on draws, the rock can start curling immediately. 


Break Point
The break point is the point where the rock noticeably begins to curl and leaves the line of delivery.

Active Curl
After the rock breaks, it will continue to curl through the remainder of the shot. It will also stay on the initial curl path.

Finish
The finish is the last 6-12 feet of the shot where sweeping can control the weight and the curl. Directional sweeping is most effective during this phase. 


Manipulating the Curl Profile

A truly advanced delivery topic that can be discussed is manipulating the curl profile through line of delivery and release modification. Manipulating the curl profile and line of delivery can produce dramatic results. Use the following techniques when you are proficient at the basic delivery and release mechanics. 


Directional Sweeping (melting and scratching)
In the Sweeping Section, directional sweeping is discussed further. It is possible to change the curl profile using diagonal sweeping techniques. Corner sweeping as it was known in the 1990's is a method of controlling the amount of curl (mostly to keep the rock straight). Of course this happens after the release. It is also known as differential sweeping. This, and directional sweeping is covered in detail in the Advanced Sweeping section.


The Quick Release
The term positive release was used in the Delivery Section to help curlers with a more predictable curl of the rock .It means making a move slightly toward the skip's broom by extending the arm from the flexed position and rotating the rock at a certain rate to ensure a 3 revolution spin.
The quick release provides more extension and more rotation, extending the free run and straightening the overall curl profile (less differential friction).Instead of applying the turn over a 3-4 foot area, try applying the turn over a one foot area. This will increase the rotation to 4-5 revolutions. Quick releases work well on ice that curls 4-6 feet. The positive action at release changes the curl break point, making it happen later in the shot.


Setting the Rock
Setting is the positive outward motion at release. This takes the rock off the line of delivery to the wide side and creates a shallower curl profile (straighter). Extreme curl conditions may warrant the setting of the rock.


Spinner
The spinner is the radical version of the quick release. Spinning the rock (6+ revolutions) at release dramatically increases the rotation and virtually eliminates the friction differential under the rock. This results in a very straight curl profile.


Why do people do this?

Three reasons; some players need to take the curl out of a rock without throwing extra weight. For example, a draw that needs to sneak through a port and stay straight to finish. Another reason would be to add some predictability to a known bad rock (either a pig or cutter).Rocks with pits will run truer if more rotation is added. The other is very swingy ice or flat ice due possibly to a warm (or worn) ice surface.


Squaring Off
In simple terms, squaring off refers to the deliberate shift from standard L.O.D. acute angles to known field of play vectors in order to prevent a subsequent opponent counter-play. Just kidding, see the next paragraph for a better explanation.


Square Release
The square release is used on very straight ice. It means slightly over rotating the rock past 12 o'clock and releasing the rock inside the line of delivery. This causes the opposite effect of the positive release. It changes the break to an earlier point. There are two ways to square a rock.

Slide wide and turn the rock in with a normal release

Hold the handle straight and release inside past 12 o'clock

This happens quite a bit in regular play but it's done inadvertently. You may have heard the term dump at release. Squaring is a controlled version of the dump.


Jump Sweeping
Jump sweeping is a cool way to say early sweeping. If the sweepers jump the rock early, they can lengthen the free run. This can be done deliberately or as a result of early sweeping for weight.


Axis Analysis - A CurlTech Exclusive

Axis analysis regarding the curling delivery is an industry first. CurlTech created this type of analysis. In a proper curling delivery/slide, the body should be fixed over three axis'. An easy way to troubleshoot a delivery/slide is to look at the three primary axis' to lead us in the right direction.
The curling delivery involves three primary axis':

In addition, and on a more complicated level:

During a proper delivery, the body is fixed and there is no rotation around any axis throughout the delivery. The only visible movement in the delivery is the arm extension and release rotation. Rotation around these axis' is will create problems.
Let's discuss how this happens.


The Vertical Axis
This axis runs straight up and down and perpendicular to the line of delivery. While in your extended delivery position, the axis runs from the ice surface, through your mid-section and continues to the ceiling. In a proper delivery, the body (as it relates to the vertical axis) should be fixed through release with no rotation around this axis. The shoulders and waist should be square to the skip's broom.
There are two types of vertical axis problems:

The position of your trailing leg and foot has an effect on the vertical axis, both fixed and rotational. A trailing foot angled to the right (outside) will cause a clockwise rotation while the left angle will cause the opposite (counterclockwise).Experiment to confirm. Fixed Vertical axis problems exist when the curler slides out of the hack and is fixed in an out of square position. This can be measured in degrees off center. The most common fixed axis problem is a delivery 5-15 degrees to the right. Another common vertical axis problem is caused by what's known a closed hip. In the proper delivery, the hips are square to the broom, perpendicular to the line of delivery. The upper left leg is extended to the left at 10-30 degrees. A proper delivery at these angles has an open hip. Angles of less than 10 degrees or anything right of the line will close the body and result in an out of square position to the right. Rotational problems exist when the player slides out of the hack and rotates around this axis during the delivery. The most common problem is a rotation to the right (clockwise).This is also known as a fishtail. The cause of the problem is an incorrect push from hack and compounded by a possible out of balance situation. The fishtail may correct itself by rotating counter-clockwise resulting in severe lateral forces being applied to the rock.
One type of vertical problem is balance related. In an effort to slide smoothly, some curlers will bend the trailing leg at the knee while keeping the lower leg flat on the ice (some as much as 90 degrees).This creates a comfortable position to balance in because the back leg is supporting the delivery. The problem exists when the bent leg forces the waist and shoulders to be out of square to the right as mentioned earlier. What does this look like out on the ice? Because the out of square curler is facing to the right, they will have a difficult time staying on the line of delivery. They will miss to the right in almost all cases. Out-turns will seem to float out and in-turns will appear to be narrow and curl more.


The Horizontal Axis
This axis runs across the body and perpendicular to the line of delivery and parallel to the ice. Imagine a line from sideline to sideline, parallel to the ice and running through your mid-section. Again, the body should stay fixed throughout the delivery. The most common horizontal axis problem is movement of the upper body at the hips. Fixed horizontal axis problems occur when your upper body is too low or too high. A variable problem is the upper body moving up or down during the slide.


The Longitudinal Axis
This axis runs parallel to the line of delivery. Image a line from head to toe. Rotation around this axis is the most common. It looks more like a tilt in the body during the slide. It's caused by an out of balance slide where the sliding foot is too far right. This causes a noticeable reliance or lean to the left on the broom or sliding device.
A Compound Longitudinal problem exists when the body is turned to either side at the waist. It is most common when a player leans to the right, putting the delivery out of square at the upper body only.


The Parallax Syndrome

Parallax refers to sighting angles. The dominant eye discussion revolves around this. Imagine a line that starts at the broom, passes through the extended hand, up the arm to the shoulder. This is the true line of delivery. Since the shoulder is about six inches from the right eye and 8 or 9 inches from the left, neither eye is behind the true line. This results in sighting the broom at a slight angle (parallax).This can be confusing at a minimum. Right eye dominant right-handers get a closer look than left eye dominant players.


The bottom line is that if you're right eye dominant, you have a parallax sighting problem. If you are left eye dominant, it's worse.

Don't Over-think the Parallax Problem
This issue has been discussed for decades. Many instructors identify the parallax problem as a key problem in the delivery, particularly left-eye dominant curlers, and try to create solutions. Turning your head, leaning to the right, drawing the rock to the toe are all attempts to solve a problem not worth solving.
The reality is that we all feel what it's like to throw the rock straight. Very few of actually see it. It's important to have a coach or teammate view the shots during practice since it's very difficult to see from the throwers angle. Video analysis really helps here.


Using a Backswing

The deliver by CurlTech is very versatile. It can generate power and finesse to throw most of today's curling shots. Occasionally, you will face a situation where extreme power is beneficial. Extreme power can be used for shots like the following:

To attain extreme power a backswing can be used. Adding a backswing delivery to your no lift delivery can allow your team to add more shots types to your game plan. A backswing delivery is different in a few ways. Instead of simply swinging the rock with your normal delivery, a few modifications are needed to throw the rock accurately. Let's start with the hack foot. Using a no lift, the hack foot is straight in the hack pointing parallel to the line of delivery. With a backswing delivery, the hack foot must be turned slightly to allow the rock to pass by the ankle without taking it off line. The next change is the weight shift. With a backswing delivery, the hips to not move behind the hack as in a no lift delivery. The hips stay over the hack. The sliding foot should be placed back in a similar fashion to the no lift but no weight is placed on it.

The rock should be swung back between knee height and waist height. When done properly, the swing delivery can generate hits weights in the 2.0 - 2.4 split range. Be careful. The line of delivery changes with a backswing. If you normally draw back to your toe, the backswing line will be 4-5 inches to the right.

Only One Hack?

It's clear that when you look at the design and placement of the hacks, they were designed for curlers with a backswing delivery. The right-hander's hack (left one) is three inches left of the center line. This puts the entire body left of the centerline at setup. This was required to clear the leg in the backswing when everyone lifted to rock. With almost all new curlers learning the no-lift delivery, the question is constantly asked, "Why can't we design a single hack for both right and left-handers?"
This may seem like a simple question. It would be if all players used the no-lift delivery. The main reason we have not seen a uni-hack is because there is still a percentage of back swing type deliveries. At the time of this update no instruction includes the backswing delivery and fewer and fewer curlers use it.

The CurlTech Hack is a prototype hack made of a single piece of rubber, 8 inches wide and slightly concave. It is placed with its center point on the center line. This allows most curlers to setup with the rock on the center line creating symmetry for both turns and for right AND left-handed curlers. Curlers using a backswing will have to adjust to the new geometry.

What's best for the existing hacks?

The best thing for no-lift curlers would be a hack that is closer to the center line. This of course is unacceptable for a back swing curler. An adjustable hack is the answer. A single hack on a sliding track with five positions:

Right-hand backswing - three inches left of center

Right-hand no-lift - one inch left of center

Right and left no-lift drawing to the toe - center

Left-hand no-lift - one inch right

Left-hand backswing - three inches left

Of course as soon as you develop options for delivery, people will immediately use it to their advantage.

Advanced Shot-Making Troubleshooting

The above chart covers some common delivery problems related to mechanics. There are some other shot-making problems that can be addressed. All missed shots can be put into one of four categories.

Delivery Mechanics
Many shots are missed due to improper deliver mechanics. In this case, the curler was not trained properly or proper training was not followed by enough practice and repetition.


Mental Mistakes
Some shots are missed due to mental mistakes. Not thinking the shot through or rushing the shot. Not fully understanding the skip's call. Not thinking about the pro and amateur-side misses.

Physiological Breakdowns
This problem is slightly different and combines the mechanical problem with the mental problem. This is when the stress and anxiety of a given situation affects the mind AND body. The most common problem is nervousness that causes excitability and an inability to control the power and muscle movements. If the heart rate is high or butterflies exist, the tendency is to over throw due to an increase in adrenaline. This is why many last shot draws are too heavy. If the body is susceptible to nervousness you will either come out too hard and heavy or come out hard and heavy then pull back (missing short).

External Factors
Everyone is familiar with external factors. External means outside the throwers control. These include sweeping errors on draw shots and line call errors on take-outs. Bad information on ice speed or bad rocks is also a good example.


The Coach's Role in Troubleshooting

The job of a good coach is to identify why shots are being missed. The coach must work at two levels:

Coaches must review missed shots throughout the season to determine if the problem is systemic (faults in the delivery, physical problems, behavioral and mental issues) or game induced (unusual conditions, mismatched rocks, high degree of difficulty type shots, etc.).Systemic problems can be addressed off the ice and in practice. Game problems must be addressed during the game which is very difficult for curling coaches since curling is a passive coaching sport.


Breakdowns at the Highest Level
Curlers at the World/Olympic level miss shots. There are many reason but the top two are mental breakdowns and small mechanical breakdowns. Let's talk more about the mechanical breakdowns that occur at the highest level. (or at the next lower level preventing them from getting to the top).Thera are two main factors when it comes to high-level mechanical breakdowns.

Tempo and Foot Delay
Lack of tempo and proper foot delay result in inconsistent forward energy. As mentioned many times earlier, the large muscles in the legs cannot calibrate draw weigh effectively enough, particularly in high stress and high fatigue situations (world and Olympic play).Master the tempo and delay skills and own draw weight.


Lateral Energy During the Slide and at Release
A proper release requires 100% of the rocks energy to stay on the line of delivery as its being rotated and leaving the hand. Even the top players may add lateral energy to the rock at release. This may work in many high level games and can be corrected by good sweeping, particularly when the lateral energy is applied inside the line of delivery. In this case good sweeping can lengthen free run and limit active curl. The real problem is when lateral energy is applied outside the line of delivery. It is unproven that directional sweeping can make a rock curl more at takeout weights. Outside lateral energy is almost always bad. It lengthens the free run and completely changes the curl profile. In some rare cases, lengthening the free run is necessary. Outside lateral energy an work in the following situations:

Delivery Theory Flow Chart

Below is a revolutionary new way of thinking about how and why the delivery works. Use it to ask questions about your delivery and to help troubleshoot. The chart clearly shows how all of the delivery components are interrelated.
Using the chart:

To ask "How" questions, work down the chart.

To ask "Why" questions, work up the chart.

For example:

How do I achieve consistent weight?

Why do I need good balance?

All of the terms used in the chart are described in the Delivery section.


Advanced Equipment

Equipment and Performance
Having the proper equipment is an important component to playing well. Since there is an endless list of equipment, decisions on the best equipment to use may be difficult. The following is a list of subtle differences that you should consider.


Shoes
All serious curlers must have dedicated curling shoes. There are a few options. Several manufacturers make curling shoes. CurlTech recommends Teflon as the slider material. Remember, your balance can depend a lot on your shoes. The better the sliding platform, the easier it is to slide balanced. In addition to performance, your shoes should be comfortable and warm. Teflon can be customized for additional performance. A company called Balance Plus makes a slider with shallow holes drilled into the bottom. This provides a perimeter effect similar to a perimeter-weighted golf club. The holes provide a greater sweet spot in the center of the slider, increasing balance performance.
CurlTech recommends the Balance Plus Delux shoe with the full ? slider and two holes.


A slightly less expensive alternative is to purchase a good pair of athletic shoes and have the slider added to it. The Balance Plus company can add their slider to most flat-bottom shoes.


Sliders
Sliders come in various speeds, shapes and materials. Generally, the advanced curler will use a slider that provides the least amount of friction and provides the most stability. The thick Teflon slider is the most common advanced slider and can be used be the novice and advanced curler .It is fast and quiet, provided very little friction. The only other slider that may be faster is one made of stainless steel. Stainless steel sliders are cost prohibitive for most curlers and don't provide the much additional performance enhancement. Other advanced sliders include the red brick slider. It is a fast slider that was effective on poor or rough surfaces found many years ago.


Brushes and Brooms
The terms brush and broom are interchangeable. Natural bristle brushes were popular in the 1980's and 1990's. Horsehair and hog-hair brushes were the standard. Today, the standard is synthetic (hair brushes are banned in championship events due to the extreme scratching damage).Synthetic brushes are made of Cordura or other high-friction material. The biggest advantage to using synthetic brushes is the weight-to-effectiveness ratio. They require less effort to create friction resulting in much more efficient sweeping. They are also much cleaner due to the reduced amount of shedding. Curlers playing on multiple teams such as league play should purchase a broom that allows them to sweep on both sides of the rock.


As a rule, don't purchase a straight, fixed-head broom. Some type of adjustable or swivel broom is a must for sweeping effectiveness on both sides of the stone. Straight brooms are for sliding and skipping.


CurlTech Choice:

Any swivel head, light weight brush

Any other adjustable type

The brooms listed above are for individuals sweeping on both sides and playing on different teams. They will work on competitive teams but are not the most effective. A light-weight, fixed angle broom is the most effective for team play. It allows you to twist the handle and apply pressure to on edge.

Using a "Stick"

Throwing with a stick (or other throwing device) has allowed many curlers to keep playing beyond their "traditional delivery" days. In fact, many curlers that transition to a stick find that they can throw take-outs with the same or more weight than with the traditional delivery.  Stick leagues are available at some clubs.  The stick cannot be used at anything leading world play as the WCF rules states the rock must be thrown with the hand.  In many cases,  although takeout weigh has increased, draw weight consistency using a stick can be elusive.

Our wheelchair curling friends demonstrate amazing shot-making skills, especially on calibrating draws. All with no sweeping.  The secret is in how they use the throwing stick.  Wheelchairs must remain stationary so all of the forward energy comes from the arm and they generate smooth power by starting with the arm/elbow in the back position.  A smooth and consistent push forward and a positive release equals a sustainable and repeatable delivery.

Let's talk about this key stick principle for able-bodied curlers.

Try this: