Bow Tuning – Advanced Tuning

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So far in this series, we started by discussing the basic Olympic recurve bow setup. We covered what tools you require for bow tuning and to basically setup your bow. This included limb alignment, how to measure, installing the arrow rest, nocking point and setting up your basic center shot.

Now that your bow is basically setup, you have been practicing with it and have a fairly consistent arrow group it is time to do some advanced tuning of your bow. Remember that basic step-up and tuning can be done quickly to get you started however advanced tuning is a time consuming task through trial and error.  Proper shooting technique is always the first thing every archer should focus on. If you are still struggling with the basics then get your bow basically setup and work on consistency.  To avoid massive amounts of frustration, it is very important to focus on changing and tuning one thing at a time. Read my earlier blog about Consistency and Change.

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Next we will focus on individual areas for you to tune such as nocking points, bowstring fit, centering, clearance, brace height, sight alignment, tiller, clicker and plunger adjustment. Since I already created several blogs about tuning specific components your bow, you should start by reviewing the following…

Sight : Following the arrow and adjusting your sights

Clicker : Adjusting and shooting with a Clicker.

Arrows and various tuning methods : Arrow Series – Part 8 – Fine Tuning and Numbering

Remember, bow tuning is an advanced technique and if you can I recommend you employ the knowledge and experience of a trained coach, since another pair of eyes can really help make the difference between a good tuning and perfection. In the next part of the series we will continue and take a deeper dive into the remaining areas of your bow that can be tuned. 

Bow Tuning – Basic Setup

IMG_7304For a beginner, if you purchased your bow from an archery shop, hopefully they worked with you to “basically” setup and tune it for you. If you are in the unfortunate situation were you do not have a pro shop near by and/or purchased your bow online you will need to perform the basic setup yourself. This may be a difficult task if it is your first bow and you are a green horn to archery. Shooting form has the most impact on your performance and you need to be relatively consistent to see any major impact from bow tuning.

That said in the first couple of blogs, I will give a basic overview of how to setup your bow so you can begin shooting with it. Later in the series we will discuss the intricacies of tuning each area of the bow.

For any bow setup you should have a couple of basic bow tuning tools

IMG_7604Bow Square: T-shaped tool for measuring brace height, tiller and nock position.

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IMG_7606Nock Pliers:  Specially designed pliers for installing nock points.

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IMG_7608Bow Stringer: Provides a safe and convenient way to string recurve or long bows.

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You may also need an Allen Wrench Set (Hex Keys), Pliers, adjustable wrench, scissors and/or various screwdrivers depending on the composition of your equipment. Reference the manufacturer’s manuals for necessary tools. There are a ton of additional bow tuning tools such as a pressure button measuring tool, bow scale, electronic chronograph, bow press and leveling tools. These are optional and will not be used for the basic tuning.

Completely assemble your bow, for a quick and simple step-by-step guide check out my earlier post about Putting an Olympic Bow Together.

Make sure you gather all the pieces that you are going to use including the riser, limbs, stabilizer system, string, nock, arrow rest, sight, clicker and plunger. It is important to start with everything when tuning, since even one change can have you starting all over again.  Start by making sure that all the pieces fit together, and are correctly assembled so you have a tight fit.

In the first blog we will make sure your limb alignment is correct, the string and brace height are within specifications, and the tiller is properly set so the limbs are correctly set. Olympic bows are typically take-down bows with risers that have International Limb Fittings (ILF) so you can easily replace them. It is very important that limbs are aligned straight and that both limbs are aligned with the center of the grip. Some risers ILF slots can be adjusted side-to-side and you may need to make some adjustments to align the limbs.

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For good limb alignments the things to check are…

  • The limbs are correctly installed and the top limbs in the in top slot, and bottom in the bottom. (this may sound obvious but it would not be the first time someone got their limbs mixed up)
  • The string is lined up with the center of each limb and the center of the grip.
  • The limbs are not twisted – check out my earlier blog about Twisted Limbs.

brace-heightNext we need to make sure you are using the correct string for the bow. This is measured using the brace height or the distance between the center of the string and the grip when the bow is strung using a bow square. Each bow manufacturer provides the specific tolerances for the brace height however the following chart is a pretty good guide.

62” Bow            7 3/4″ – 8 1/4″              197 – 210 mm
64” Bow            8” – 8 1/2”                    203 – 216 mm
66” Bow            8 1/4” – 8 3/4”              210 – 223 mm
68” Bow            8 1/2” – 9”                    216 – 229 mm
70” Bow            8 3/4” – 9 1/2”              223 – 242 mm

If your brace height is just slightly out of range you can try to add a couple of string twists to adjust within the specific tolerance however never put more that 20 twists in a string.

tiller-measureNext we need to make sure the correct amount of draw weight is shared between the limbs. The difference between the top tiller and the bottom tiller will effect the bow reaction on release and your ability to hold steady at full draw and aim. Your hand on the grip is centered in the bow however your arrow is actually above center, the bottom limbs needs to be slightly heavier to compensate. This is accomplished on an Olympic bow using the adjustable tiller. Most risers are shipped with the tillers adjusted to the correct depth. Adjusting the tiller is an extremely advanced bow tuning technique, and should ONLY be adjusted by a someone with experience. The thing for you to check is to make sure that top tiller is about 1/8” to 1/4″ (3-8 mm) greater than the bottom tiller, if not take your bow to a professional pro-shop or coach to help you adjust it.

In the next post, we will cover installing the arrow rest, nocking point and setting up your center shot.

Bow Tuning – A Simplified Series for Beginners

IMG_7304Your bow is  very personal to you and should be tuned specifically to you and your shooting style. Since there are tons of in-depth, technical articles about bow tuning produced by many organizations and manufacturers, my goal is to simplify the concepts for beginner archers. Although, my primarily focus will be an Olympic recurve bow, some or most, if not all, the principals can be applied to other disciplines.

In this series we will discuss, but not limit to, nocking points, bowstring fit, centering, clearance, brace height, sight alignment, tiller, clicker, plunger adjustment and discuss various tuning methods. Remember that basic step-up and tuning can be done quickly to get you started however advanced tuning is a time consuming task through trial and error.  Proper shooting technique is the first thing every archer should focus on. If you are still struggling with the basics then get your bow basically setup and work on consistency. From there, a well tuned bow can help compensate for personal idiosyncrasies and help you achieve the maximum performance.

So, in preparation for this series, review and ensure you have the correct equipment for you. You need to have equipment you can use. If the bow is too small or light, or alternatively too heavy, in-depth tuning is not going to provide many advantages. Alternatively, if your equipment is just above or below were you need to be; advanced tuning can help rein a bow in. Also, make sure you have selected the correct arrows for your setup. Review my Arrow Series about arrow selection to make sure you have selected arrows that are best for you.

StudyingAlways remember that there are several steps to properly tune your bow for maximum performance. You should record every adjustment so you are able to retrace your steps should an adjustment provide negative results. Remember to adjust only one thing at a time and then test. Remember that even one piece of new equipment will require bow tuning and the amount will depend on the importance of that piece. For example, a new plunger a little bit of tuning and new limbs with higher poundage means you may be starting from square one.

Bow tuning is an advanced technique and should be only attempted by archers with at least a good understanding the bow mechanics. I recommend you employ the knowledge and experience of a trained coach. I still work with my coach to tune any new bow that I receive, since a second or third pair of eyes can really help make the difference between a good tuning and perfection.

Archery: One of the Safest Recreational Sport… No Really!

safety-firstThere is often a misconception that archery is very dangerous. Although a bow and arrow can be a lethal weapon, archery is actually one of the safest sports because there is a culture of safety. Statistically, archery is one of the safest recreational sports there is with only 0.65 injuries per 1000 participants as outlined in the USA National Electronic Injury Surveillance System and represents the hospitals which actually record the information. Check out the Archery Safety report from Arizona State and Fish Department from 2004.

This is largely because of the culture of safety that encompasses the sport. All coaches start by instructing their students with the fundamentals of archery safety. I remember my first lesson was about safety first. Nowadays, I regularly shoot through my house for practice and we never worry about danger because of the culture of safety within my house. Everyone follows the basic archery safety rules. For archers there are two basic areas of safety that you should maintain, personal safety including equipment and field or range safety.

Personal Safety

  • Always shoot with well maintained equipment and arrows
    • Always inspect your equipment and arrows before shooting
    • Before shooting each arrow inspect the arrow and nock for damage
    • Cracked or bent arrow must never be shot.
  • One should always use a bow-stringer for longbows and recurve bows. This will reduce the possibility of damage to the bow and injury to the person.
  • Shoot with good archery form ensuring you wear proper attire and a properly positioned arm-guard.
  • Never, ever shoot while intoxicated or with anyone who is.

Good Rule of Thumb: If in doubt, stop and get it checked it out.

Field and Range Safety

  • When shooting…
    • Do not shoot with ANYONE in front of the shooting line
    • Do not nock an arrow while anyone is in front of the shooting line
    • Only nock an arrow whwn you are on the shooting line and after the signal to start shooting
    • A loaded bow is only pointed at the assigned target
    • NEVER EVER point an arrow at anyone, whether on a bow or not.
    • Arrow must never be shot straight up into the air
  • When not shooting
    • Pay attention and be respectful of other archers
    • Once finished shooting you must be behind the shooting line and paying attention
  • When retrieving arrows from the target
    • Leave your bow behind the shooting line (hang-up your bow), you will need two free hands to collect your arrows from the target
    • Always walk forward to collect the arrows, never run.
    • Always pick-up arrows on the way first. Whether they yours or not.
    • Always walk up to the side of the target butt, so as to not to accidentally walk into the rear of the arrows lodged in the target.
    • One person at a time should withdraw their arrows from the target.
    • When withdrawing arrows from the target, ensure no-one is standing behind you. Pulling arrows may require a lot of force and they can come out of the target suddenly and could hurt someone standing behind them.
    • When carrying arrows, always hold them to your side with the points down.
    • Make sure that EVERYONE has returned behind the shooting line before starting the next shooting end.

Individual ranges may have additional rules specific to their courses, all ranges will adhere to the basic archery range safety rules. Whether you are a beginner or an experienced professional archer, if we all continue to practice the culture of archery safety we can enjoy the sport for many years to come.

Rests

Basically an arrow rest is part of your bow setup that holds the arrow in place, ready to be shot. Allen asked…

What kind of rest would you recommend for a beginner recurve shooter? I’m a COMPLETE newbie to archery, so I blindly went with the archery shop guy’s recommendations when buying my first bow. I ended up buying a Samick Polaris that he set up with a rug rest. Is this a bad kind of rest to use? Wouldn’t the two non-index fletches hit the bow on the way out? My arrows tend to hit the target at an angle instead of perpendicular, so I wonder if the rest could be causing it.

First lets cover the various types, most people say there are four basic types of arrows however I believe there are five; shoot-thru, containment, drop-away, pressure/plunger rests and the additional shelf. The shelf is often overlooked because it is part of the bow, however you do “rest” the arrow on it.

Here is a general overview of each type.

Shoot-thru (or prong) rest : A two-pronged arrow rest with a gap between and spaced about two-thirds of the width of the arrow to create a cradle. The arrow sits on top of the prongs with one fletching pointing down between them and is usually spring-loaded to allow additional clearance for the fletchings. These rests can be tricky for beginners because the arrow can fall off with wind or bad form.  They are best for hunting and the use of a mechanical release.

Containment rest : A totally encircled or a simultaneous 3-point contact arrow rest holding the arrow completely in place until release. These are the most common choice for archery hunting, they are relatively easy to install and tune. Great for beginner hunters since the arrow will not fall off the rest.

Drop-away (or fall-away) rest : Designed to drop out of the way upon release and therefore eliminate any chance of contact with the arrow. Activated by the release of the string, the rest holds the arrow long enough to keep straight and needs to drop out of the way before the fletching reaches the rest. Since this can be very tricky to tune; it is best suited for a compound bow. It is popular for hunting with large fixed-blade broad heads and helical fletchings.

Pressure/Plunger rest: Used commonly by finger shooters (no-mechanical release), they are designed to counter-act the horizontal oscillation from release with your fingers. Standard type bows without a cut-away, typically use a simple flipper rest (a rest with an additional “flipper” that acts like a plunger to help push-back against the pressure). Bows designed with a cut-away for your center shot typically use a rest along with an adjustable plunger. A pressure rest is used on Olympic bows and can be used be any finger shooter.

Shelf: Most traditional longbows and modern recurves bows are now designed with a cut-away area in the riser which includes a shelf area. For this type of bow instead of a pressure rest you can choose to shoot off the shelf. An arrow rest is attached to the shelf of your bow and is usually installed with an arrow plate to the side. They serve as protection for the bow and arrow and act as a soft, smooth surface for the arrow to be shot from.

Selecting a rest depends on a list of things including…

  • Type of bow (compound or recurve)
  • Chosen application (hunting or target shooting),
  • Type of release (finger or mechanical)
  • Budget (cold hard cash)
  • Experience (your ability to tune the rest and bow)
  • Form (some rests are more forgiving)
  • Tradition and historical nostalgia
  • Competition division (division restrictions)
  • And personal preference (bling factor)

There are a ton of rests available on the market and most bow manufacturers follow the same AMO (Archery Manufacturers Organization) standards. Therefore the drilling and tapping for the majority of bows are universal however before you purchase or upgrade make sure a selected rest will work and function with your bow.

A rug rest is a type of rest for a shelf and could be a very good selection for your shooting style if you are shooting traditional however it would not be the best selection for an Olympic archer or a compound hunter.  I am not in a position to recommend the best rest for your bow, since the bow is only as good as the alignment between the rest, release and nocking point. Obliviously, a better quality rest for your style of shooting can impact your accuracy.

To specifically address… My arrows tend to hit the target at an angle instead of perpendicular, so I wonder if the rest could be causing it.

A rest is only one small piece of the bow, and has very little to do with controlling the oscillation of the arrow. I would personally need to watch you shoot and inspect your bow to provide any valued and specific advice. There are a ton of things that can cause your arrow to impact the target on an angle. The bow may need tuning, you may be plucking the string, the arrows may be too stiff or too flexible, and a lot of other things.

Quick Insight: “Bows only perform actions as directed by you; so make sure you have good form first.”

For more information on good form check out my website page The 10 Basic Steps of Archery and to understand controlling arrow movement such as oscillation, check-out the complete Arrow – The series.

Arrows Series – Part 4: Spine, Flex and Stiffness

Before we discuss the topic of arrow spine, for proper safety and best performance, arrows need to match your entire bow setup. If you change draw weight, draw length, limbs, riser size, etc. this will affect you arrows. You may need to adjust the arrow length or require different arrows.

Arrow Myth:  An arrow is always straight.

Arrows SHOULD be perfectly straight when not in motion. However, when an arrow is released the force applied from the string causes the arrow shaft to be compressed against the resistant static weight of the arrow point and therefore bends.

Newton’s First Law of Motion: Every object in a state of uniform motion (rest) tends to remain in that state of motion (rest) unless an external force is applied to it.

Since the force applied is greater than the  resistance (weight of the tip), the arrow is propelled forward, and the shaft continues to flex and oscillate as it straightens itself. Arrow shafts that are either too stiff or too flexible will not fly well and will impact the accuracy of your shots or fail causing damage and/or injury. Therefore, we need to manage the flex properly so the arrow does not make any contact with the bow, or your arrow flight will be affected.

Important Tip: Arrow spine refers to the arrow shaft’s degree of stiffness (how much the arrow resists being bent) and is called spine deflection.

Basic Rule 1:  Shorter arrows act stiffer and longer arrows act more flexible.

Basic Rule 2: Powerful bows require stiffer arrows and less powerful bows require shafts that are more flexible.

Basic Rule 3: The heavier the tip equals greater the resistance, therefore the greater amount of compression.  So, a heavier tip causes the arrow to flex more and a lighter tip increase the stiffness.

According to the American Society for Testing and Materials (ASTM) the modern standards (ASTM F2031-05) an arrow’s official spine deflection is measured by hanging a 1.94 lb. weight in the center of a 28″ suspended section of the arrow shaft and is used for aluminum and carbon fiber arrows. (I believe original AMO standard has a basic guide to use for wood arrows spine determination and uses of 2 lb. and 26” section for standard measurement.) The actual distance the 1.94 lb. weight causes the shaft to sag down is the arrow’s actual spine deflection

For example, if a 1.94 lb. weight causes the center of a 28″ arrow to bend down 1/2 inch (.500″) the spine deflection would be .500″.  Stiffer arrows will bend less and more flexible arrows with bend more.

Almost every arrow manufacturer has its own numbering system and there are no universally agreed spine sizes among the various arrow manufacturers. Simply, the lower the deflection measurement equates to a stiffer arrow and higher the deflection measurement the more flexible the arrow. Manufacturers can number, size, and market their arrows anyway they want, as long as they provide the deflection data and test using the industry standard method.

Fortunately for us the engineers have already done the math for us and manufacturers provide spine selection charts. You are able to select an arrow based on your draw length and draw weight.

So when selecting arrows a good rule of thumb is that lighter draw weight, shorter draw length and/or lighter tip weight equals LESS arrow spine OR heavier draw weight, longer draw length and/or heavier tip weight equals MORE arrow spine.

Arrows Series – Part 2: Measurements

As we start to dive deeper about arrows, my goal is to simplify the information so young archers can have a good basic understanding; it is not meant to be all in compassing or a physics lesson, remember I am still learning too. Therefore, the next step is to understand how arrows are measured and how to determine draw length.

The Archery Trade Association (ATA) formerly the Archery Manufacturers and Merchants Organization (AMO) has the following standard for measuring draw length:

AMO DRAW LENGTH STANDARD

For Manufacturers

Draw length is a specified distance, or the distance at the archer’s full draw, from the nocking point on the string to the pivot point of the bow grip (or the theoretical vertical projection of a tangency line to the pivot point parallel to the string) plus 1 3/4”. Draw length from pivot point shall be designed at DLPP (Draw Length Pivot Point) and shall be called TRUE DRAW LENGTH.

EXAMPLE: 26 1/4” DLPP plus 1 3/4” is the equivalent of 28” draw.

For Dealers and General Use

For practical reasons not requiring precise terms, draw length is the distance, at the archer’s full draw, from the nocking point on the string to the back of the bow at the arrow rest.

EXPLANATION: The standard Manufacturers is consistent with the Bow Weight Standard as related to the pivot point. The DLPP plus 1 3/4” is compatible to previous concepts of draw length. Draw length for Dealers and General Use relieves the burden of preciseness not required for general use and facilitates determining arrow length. THIS STANDARD SUPERSEDES THE PREVIOUS STANDARD.

This can be technical and confusing, however with most recurve risers, the distance of the draw length pivot point (DLPP) to the front edge of the riser is 1 ¾”. Therefore, in general terms…

Your approximate draw length is equal to the distance from your string to the front edge of the riser at full draw.

You could use a measuring tape to measure this distance however unless you have a very consistent anchor point and good form you will have varying results, since you should measure several times. Therefore, any archer who is at the point they are fining tuning arrows for high-level of performance they should consult a professional. Otherwise, I would suggest you use the following simple method to determine your draw length.

Arms Length method

Using a ruler (or other straight stick), place one end in the “V” of your neck (where your neck meets your chest ) and relaxed, reach straight out until your palms touch the ruler. At the point for your fingers is your approximate draw length. Your arrows should always be at least 1” to 2” longer than your draw length for safety reasons and young archers often need to set their arrow length little longer ( 2” to 3” ) to allow for growth.

This gives you a basic understanding of draw length and how arrows are measured, however, things get very complicated for young competitive archers who are still developing and growing in size once you add-in arrow stiffness and flex, arrow cost, type of equipment and bow weight.

It is important to understand how things are measured so you can understand why you are using the arrows you have.  I highly recommend you visit your local archery professional for assistance.