The Delivery is the curling term for throwing the rock. This section documents of the entire delivery process. It is the most comprehensive documentation in the world regarding the delivery. CurlTech does not have its own delivery. Our organization simply documents the proper delivery. It 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 studying the curling greats and what made them great players. The new era ice conditions require finesse and precise weight control. A straight delivery (balance) with consistent weight control (tempo and timing) is described in this section. Simply stated, the CurlTech delivery is a balanced delivery with tempo.
This section contains lots of material. You will benefit from reading all the content. If are new to the sport, read the following.
This section offers a simplified version of sweeping instruction. 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 using the 1-2-3 simplified version of the delivery. When it is your turn to throw:
In addition, with practice:
The remainder of this section will cover the details of the delivery.
Before we get into the detail about delivery mechanics, let's consider some history. The methods for throwing a curling rock (the delivery) have evolved over hundreds of years. In the early days it was as simple as gaining a foothold on the ice and hurling an object forward. In the 20th century, equipment such as rubber hacks and polished rocks were introduced. It wasn't until the 1940's that the slide was incorporated into the delivery, thanks to Canadian curling great, Ken Watson. By adding a slippery surface to the non-hack foot, the curler could slide out of the hack and control the rock's weight and direction with greater ease. It was at that time that the delivery began its accelerated evolution. Almost immediately after Watson showed curlers his slide technique, they began to modify it. The ice was rough and slow, and the first modification was the toe-tuck delivery where the sliding foot was tucked under the hip by rolling onto the toe. Lifting the heel off the ice h added less friction and allowed the player to slide farther. In some cases, a lot farther. Because of this modification, a significant rule change was needed. The near hog line became a dual-purpose line as the players were not allowed to slide past it (no part of the body could cross the line). Ice conditions varied around the world, but most curling club ice was slow compared to today's standards. Some thought that sliding with less effort would improve their game and they began to roll up on the toe of the sliding foot reducing foot contact with the ice. The toe-tuck delivery was born. Although a flat-footed slide was introduced by Watson, the tuck delivery became popular for two reasons. It reduced friction on the slow surface and allowed the curler's body to get closer to the ice. Since the slower conditions were conducive to a takeout game instead of draw game, this delivery allowed them to better sight the rock toward the skip's broom on the takeout. Again, a rule change was need. Since many players were sliding, the hog line rule was changed so the body could cross the line as long as the rock was released by it. This type of long slide, toe-tuck game continued through the 1970's but some leading-edge players preferred the stability of the full-foot slide. In the early 80s, ice conditions improved dramatically due to the introduction of purified water/ice and the use of the ice scraper as regular maintenance tool. These two things improved the speed of the ice and curling began a rapid evolution to an aggressive, draw-type game and the need for the tuck delivery was no longer. In 1990 the Free Guard Zone rule further propelled the game to finesse and draws.
The delivery, described by CurlTech is a no-lift, balanced, flat-footed delivery with tempo. 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 proper delivery is made up of the following key components:
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.
The CurlTech delivery can be used by the novice curler as well as the Olympian. It is designed for ease of use AND maximum performance.
Although all deliveries can be broken down into major parts, the delivery mechanics for throwing a rock can be broken down into five total steps.
Let's break things down even further. The following is a detailed description of how the delivery works.
A Quick Note: All descriptions of the delivery are for right-handed players. Lefties please adjust.
Pre-Shot Mental Preparation
Mechanics of the pre-shot mental preparation:
It is important to visualize the weight and line before visualizing the completed shot. The entire setup and mental preparation process should take less than 10 seconds. Visualizing the completion of the shot instead of the components may train you to steer the rock toward its destination instead of throwing at the skip's broom with proper weight. Trust your skip. If the broom is wrong adjustments can be made on the next shot.
The Forward Press (#1 in the 1-2-3 cadence)
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 Drawback and Step - Rock then foot (#2 in the 1-2-3 cadence)
Here's how it 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. 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 (Figure 4). 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.
Unleashing the Power - Transitioning from the Drawback/Step to the slide.
The Foot Delay
The Foot Delay Process
How to Delay the 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 slow by delaying the sliding just a little bit and work into it.
Managing the Foot Delay
The Slide - (#3 in the 1-2-3 cadence)
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, Figure 2-8, making alignment more difficult. After the initial weight transfer, the slide should be established. This should occur at or before the tee line. Figure 2-7 shows an established delivery with an open hip, ready for release.
Video 1. 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)
The Trailing Leg and Foot
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. More on the positive release in Advanced Delivery section later this section.
Application of the Handle (rotation) in Detail
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?
Consider the following:
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
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 minor corrections on your next shot. Be objective and critical of your delivery. Acknowledge your mistakes. You can't get better without learning from them.
And there you have the five steps to delivering a rock. The next sections will describe some components to a great delivery.
The Big Three - Balance, Tempo and Release
As mentioned in the beginning of this section, there are five key 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.
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. Both of these skills are discussed further in the Advanced Delivery part of this section.
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. 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. 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.
Learn with a Sliding Device
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 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.
Proper tempo mimics the old back swing delivery. Tempo keeps your body in motion, which is good. Perfect tempo can be measured by the old one-one thousand, two-one thousand, three.
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 at release will make your shot making inconsistent.
Let's talk about how power is generated during the delivery. There are misconceptions here. There are four key power generators in the delivery. They must exist each time you throw a rock. The first two and most important are:
Followed by, to a lesser degree:
The Sliding Foot Delay
The Sliding Device
ALL new curlers should learn with a sliding device. As you begin to master the balanced delivery, transition to your broom for sliding purposes. Proficient adult curlers will 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.
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.
A note about sliders.
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.
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 8-10 feet of distance to a rock, the thrower only has to hit the weight window. Depending on the quality of your sweeping, the window is approximately eight to ten feet deep, meaning that if a rock is thrown ten feet short of the intended stopping point, the sweepers can increase the distance. 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 middle 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 size of the weight window depends on the ice conditions and the sweepers. It ranges from a zero foot window with no sweepers to approximately a twelve foot window with two world class sweepers. Which one do you want? 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.
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.
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) and to a certain degree, leg drive.
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!
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.
As you can see, the delivery can compensate for different ice conditions. Use these to start and modify as needed.
Weight Control Simplified
Understanding the conditions if necessary to play today's game. The Free Guard Zone rule makes it necessary to build your game and your mechanics around the draw shot. Timing rocks will assist your with your weight calibration.
The section on Timing Rocks for a detailed explanation of this process.
The Default Weight or Default Delivery
Try not to throw shots to their exact spot. Remember sweeping can add eight feet or so.
CurlTech receives many requests to analyze individual deliveries. 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. The following matrix will help identify any problems with your delivery. These apply to right handed curlers. Lefties please adjust.
The following examples are the most common things we see in clinics at all levels.
Sliding Foot Placement
Right Side Vulnerability
No Weight Shift
Lack of Tempo
Lack of Sliding Foot Delay
With novice and intermediate curlers, most shot problems can attributed to balance first then release. An out of balance delivery normally results in a drift to the throwing hand side, adding lateral energy to the rock. As you're drifting, any correction to the lateral energy can result in release problems.
The Wide Trifecta
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 shots are consistently wide and straight on the right side of the sheet, don't blame the ice until you fix your delivery.
Delivery Quick Reference
*Check the manual for options
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:
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 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.
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.
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 P 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.
The Sliding Device
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 allows all body parts to work together fluidly. Any delay or quickening of the count disturbs the rhythm (and performance).
Tips on Tempo
The sequence looks like this:
As mentioned above, the proper release will have a positive component. This can mean two things:
Consider the following:
As you can see, the same spilt time can produce three different shots.
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.
Line of Delivery Defined
The big question - Where should you start the rock?
Line of Delivery Options
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. For 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.
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 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.
We encourage players to feel what it's like to hit the broom.
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.
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.
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 Sweeping Section for more information. The rock curl profile has five components:
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 and Corner Sweeping
The Quick Release
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
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.
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.
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
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
The Longitudinal Axis
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.
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
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.
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.
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?
Of course as soon as you develop options for delivery, people will immediately use it to their advantage.
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.
The job of a good coach is to identify why shots are being missed. He or she 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.
Tempo and Foot Delay
Lateral Energy During the Slide and at Release
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:
All of the terms used in the chart are described in the
Equipment and Performance
CurlTech recommends the Balance Plus Deluxe 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.
Brushes and Brooms
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.
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.