The Evolution of the Riser

2012-MidasIn this series I am going to discuss the evolution of the riser or the structural strength of the bow which houses the handle, to which the limbs are attached and other various accessories.  Originally the riser and the limbs were actually one piece, as you would see in a bare bow or instinctive bow, however in most modern bows the riser is completely independent component.

Historically, the original construction material was wood and sometimes combinations of different types of wood. Other historical materials included horn and sinew (A piece of tough fibrous tissue uniting muscle to bone or bone to bone; a tendon or ligament) to create composite bows.  Beautiful laminated wooden bows and risers are still manufactured for lightweight, beauty, tradition, and style.

1212210010_L1Although some bows are still manufactured from various laminated hardwoods and are quite durable, the development of other modern components with materials such as carbon arrows and various strings, wooden risers were strained.  Therefore bow makers were forced to invest in the development of other more durable materials for competitive archers to maintain that competitive edge.  Competition target archers need enough arrow speed with great sight marks, with minimal string creep, since they practice a lot of shooting (anywhere from 150 – 1000 arrows a day).  Wooden bows will eventually break under the additional loads of pressure applied from the stress and strain.

Today there are two primary types of risers used by Olympic target archers, CNC machined aluminium and Carbon fibre or a combination of the two.  In the past, other materials and manufacturing methods were used such as forging and casting.

Forging

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This method hammers a metal bar under high temperature and high pressure that results in an extremely strong riser. Typically forging is an expense development process which requires machining, straightening and painting with very few variations.

Casting

ben-castingUsually a mix of aluminium and magnesium were developed with either die-casting or sand-casting methods.  Still available in the market today with low-to-mid range bow are a relatively cheap to make once you have the mould.

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CNC Machined Aluminium

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A computer controlled method to machine a riser from stress-relieved aircraft grade aluminium alloy until they weigh less than 3 pounds. Sometimes, in order to reduce the costs, risers can be extruded through a die to minimise the amount of machining required. CNC risers are usually anodised to provide a hard wearing finish.

Carbon Fibre

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A method of layering synthetic fibres usually over a dense foam core mould, which is cured with resin epoxy to develop an extremely strong and lightweight riser. Although this method can be expensive to develop and test with, the process has almost infinite number of possibilities in terms of strength and flexibility of design.

Currently, the market is primarily CNC Machined Aluminium with overlayed Carbon Fibre to gain the best of both worlds. Who knows what the future holds for risers as target archers look to find the competitive edge and manufacturers investigate in cost savings.

String Alignment

Consistency is the key to a successful archer. In an earlier blog, we developed a consistent anchor point to develop a starting point for your hand and grip to help develop consistent vertical groupings. Now we need to address consistent horizontal groupings through the use of string alignment.

IMG_8525So, while at full draw at your anchor point, you should be able see a blurred image of your string; align this “blurry” image of the string with the riser. If it’s slightly off, rotating your head either left or right slightly will correct this. (Remember to maintain your anchor as you quickly check for this alignment). If the string picture is in the wrong place, then your aiming accuracy will be off and the result will be groups which are spread horizontally.

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Quick Tip : Note that sometimes a dark string is difficult to see against a dark riser, therefore try adding a small strip of white tape along the inside of a dark riser to help see the string.

Ideally, you should try to use the same spot for all distances, however this can be different for all people. It can help some archers by aligning the string on the inside of riser for close distances, middle of the riser for middle distances, and outside of the riser for long distances. The best alignment it is different for everyone because everyone has different head and nose structures. Therefore, you will need to experiment with the string alignment until you have the perfect string alignment for you.

Quick Tip: If you are having difficulty seeing your string, try closing you non-dominant eye.

Remember once you have your string alignment, changing things such bow length, draw length, arrows or anything else can effect your “perfect spot”. Consistent form is vital for consistent groupings, if you get a consistent string alignment, the bow will be at a consistent horizontal angle, and your horizontal grouping should improve.

Moving Clicker Question?

Back-musclesConsistently using a clicker is one of the most difficult things for an archer to master, however once mastered you will love your clicker. Check out my earlier blogs about clickers and learning to shoot with a clicker.

Recently, one of my readers asked:

This is a bit late of a response, but I’ve started my clicker training and one of the things I’m having trouble with is nocking the arrow behind the clicker. I move the clicker with my fingers while nocking my arrow, but every time I do so, I move its position. 

First, there are three types of clickers…

riser-mount-clickerRiser-mounted clickers
The clicker is mounted directly on the risers and is still relatively vertical about 1-2 inches beyond the pluger/ pressure button.

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extended-riser-mountExtended Riser-mounted clickers
The clicker is still mounted to the riser however the click arm is adjusted horizontally beyond the face of the risers (1-3 inches beyond the front edge of the riser).

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sight-mount-clicker

Sight-mounted Clickers
The clicker is mounted to the arm of the sight and is used for archers whose arrows are well beyond the face of the riser (2-10 inches beyond the front edge of the riser at full draw).

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Ideally, the clicker should be positioned as vertical as possible and should extended a couple of mm beyond the bottom of the arrow. If the clicker sits on the top half of the arrow it may apply downward pressure and cause inconsistent arrow flight. So select a clicker that can be mounted as vertical as possible.

Next, I suggest you mark your riser/sight arm so you can ensure the clicker position before every use. Part of your pre-game bow assembly is to verify the clicker is in the correct position and the screws are tight secured. If you are still noticing that your clicker is still constantly moving the screws may not be providing a tight fit. Try replacing the attaching screw or add a locking or plastic washer.

I hope I have been able to answer your question and I would love to hear more from you.

Do you have any questions?
Are there any topics you would like me to cover?

Although, I will continue to write articles about my experiences, I want to hear from you. Everyone has questions, I would love to hear yours and I love answering them. I also encourage you to leave comments or share additional information on any article on my site.

My Bow

IMG_7304Recently, one of my Tumbler followers asked me to share the details of my competition bow since they were moving towards competitive archery and wanted to know about my bow. First, I will explain the story of how I got to my current bow.

I have been searching for the perfect bow for me since the day I started shooting. Finding the perfect bow takes experimentation, trial and error. Your bow is a personal preference, so much so that in ancient times, it was a person’s most treasured possession and many kings were entombed with their bows. Finding the perfect bow may take years… and it may change as you grow, change and develop.

When I was just starting out at 9 years old, I needed a light mass weight bow. Something that would not damage my bow arm long term however would allow me to practice a lot. I was a good shot however VERY small for my age. I was able to come across the Fiberbow riser with a mass weight of only 599 grams, less than half the weight of other bows and it allowed me to practice a lot with less fatigue. This was a great bow until a couple of years ago, when I became stronger than the bow.

So before training for the Canada Games, I switched to the Cartel Midas 25” riser. I love that bow, it helped me win a Silver at the Canada Games and it took me to the World Indoor Championships in Las Vegas . This was an awesome bow for me as a cadet, however, with the change of divisions and greater distances as a junior I need to generate more power for outdoor shooting. Therefore I switched to a 23” Midas Riser and increased my limbs to 36 pounds. On initial tests I was able to top 196 feet per second and had to add additional weights to consistently settle on 194.5 fps. This is high for a recurve archer with only a 25” draw length.

IMG_7317My new bow is as follows…

  • 23” Cartel Midas Riser
  • 36# MK Archery Medium 1440 limbs
  • Cartel Spectra Sight
  • Cartel XD Stabilizer system with Midas V-bar
  • AAE Extended Clicker
  • Cartel Rest
  • Cartel Cushion Plunger
  • Custom String

Wow, this bow is amazing; I hardly feel the shot. The limbs are the smoothest I have ever shot. The limbs use carbon foam-core technology and are extremely smooth and straight. I love my new bow and it is the perfect bow for me right now. Although bow selection takes time and experimentation I hope you too can find the perfect bow for you.

Arrows Series – Part 7: Center Shot and Archer’s Paradox

Now that you have determined the arrows you should use you need to fine-tune your bow to maximize your arrows consistency. Most people think that once you set up a plunger and a nocking point it is all good to go, however that is not the case. The center shot of your arrow is one of the most over looked things when setting up a bow.

The center shot is where the arrow rests on the bow when looking behind it.  When setting up your center shot the arrow needs to be completely behind the string. Most traditional bows do not have a cut-away in the riser and the arrow has to deflect around the handle with something called archer’s paradox.

Archer’s Paradox: The term was coined by Robert P. Elmer in the 1930s. The paradox refers to the phenomenon that in order to strike the center of the target, the arrow must be pointed slightly to the side of the target. Modern use of the term has caused the interpretation of it to be corrupted and the bending of the arrow is often considered incorrectly to be archer’s paradox.

In order to be accurate, an arrow must have the correct stiffness, or “spine”, to flex out of the way of the bow and return back to the correct path as it leaves the bow. Incorrect spine results in unpredictable contact between the arrow and the bow, therefore unpredictable forces on the arrow as it leaves the bow, and therefore reduced accuracy.[1] Additionally, if an archer shoots several arrows with different spine, even if they clear the bow they will be deflected on launch by different amounts and so will strike in different places. Competition archers therefore strive not only for arrows that have a spine within a suitable range for their bow, but also for highly consistent spine within sets of arrows. (Wikipedia)

For an Olympic archer, ideally your set up should be 100% behind the string. Some people actually require the arrow lean a little to the opposite side of your riser so that the arrow can get past the bow without hitting it. You can reduce the effects of “Archers Paradox” by adding spin to the arrow by fletching your vanes or feathers with an offset or helical. It is critical that the arrow must have the correct spine so it can bend around the bow, so the fletchings do not touch anything for consistent arrow flight.

Therefore, once again I stress, for proper safety and best performance, arrows need to match your entire bow setup.

Arrows Series – Part 6: Fletching and Indexing

Now that you have cut your arrows you need to fletch them. Fletchings are found at the back of the arrow, traditionally made from bird feathers and are used to stabilize the arrow by creating a small amount of drag.

Wikipedia: Fletching (also known as a flight) is the aerodynamic stabilization of arrows or darts with materials such as feathers, each piece of which is referred to as a fletch. The word is related to the French word “fleche”, meaning “arrow,” via Old French; the ultimate root is Frankish fliukka. A fletcher is a maker of arrows.

Nowadays, there are two types of fletchings, real or synthetic feathers and plastic vanes. Some target archers have them attached to the arrow with a slight twist to increase arrow spin because a spinning projectile is more stable and helps reduce the effects of Archer’s Paradox (We will discuss Archer’s Paradox in more detail in the Part 7 of the series).

The most conventional style of indexing is a three-feather fletching where feathers or vanes are mounted to the arrow, evenly distributed around the spine of the arrow. One feather, called the “cock”, is set at a right angle to the string and pointed at the archer and the other two fletchings on the riser side are angled up and down away from the bow. This is done so the fletchings/vanes will not contact the bow when the arrow is shot. For compound archers the cock feather’s indexing depends on the type of arrow rest.

Quick Tip: Choose a different colour for the “cock” feather. It is great reminder to always point it towards you and away from the riser for proper nocking of the arrow.

Fletching an arrow is a time consuming and tedious task to do accurately by hand. In modern times, most people use a fletching jig, especially to fletch arrows with a slight twist. Check out my earlier blog about fletching jigs.

It is important to understand that once an arrow is released it starts to bend and if the arrow is not correctly indexed the feathers or vanes will make contact with the riser. This will cause the arrow to react differently than expected, distort your feathers and possibly cause damage to you or your equipment.

Arrows Series – Part 3: Draw Weight

Obviously, force is required to move the arrow forward off the bow and it is generated from the tension of the limbs through the bowstring. Therefore, when purchasing arrows you need to know your draw weight so you can purchase the correct corresponding spine size for best performance. Limbs stiffness is determined by the amount of force, measured in pounds, required to draw the bow to a 28” draw length as outlined in the following Archery Trade Association (ATA) standard.

AMO BOW WEIGHT STANDARD

For Conventional Bows

Bow weight is the force required to draw the nocking point of the bow string a given distance from the pivot point of the bow grip (or the theoretical vertical projection of a tangency line to the pivot point parallel to the string). Draw length from pivot point shall be designated as DLPP and shall be referred to as TRUE

DRAW LENGTH.

For the purpose of uniform bow weight designation, bow weight is the force required to draw the bow string 26 1/4” from the pivot point. This weight will be marked on bow as being taken at 28” draw (26 1/4” plus 1 3/4” = 28”) See DRAW LENGTH STANDARD.

EXAMPLE: Weight Adjustment Range: 45/55 lbs. Weight Set At: 50 lbs.; Hold 32 lbs. Draw Length Range: 29” – 30”

EXPLANATION: The pivot point is a more realistic measuring point (when compared to the variations of profile of the back of bows at the handle section) for establishing bow weight since the pivot point is a constant in all bows as well as the contact point of the bow hand from which the true draw length is generated.

The 26 1/4” DLPP is the approximate equivalent of the 28” draw used previously on the more massive wooden handle bows.

Therefore, your draw weight is a combination of your draw length (See Arrow Series – Part 2 Measurements) and the combination of your riser (23” or 25”) and your limb stiffness (15#-50#).

For example, a 25” riser with a 34# long limb produces a 70” bow with a draw weight of 34 pounds at a 28” draw length.  If these same limbs were used on a 23” riser, the combination would produce a 68” bow with a draw weight of 36 pounds at a 28” draw length.

However, not everyone has 28” draw length, especially young archers whose draw length will change progressively with growth. So as a rule of thumb you can add or subtract approximately two pounds for each inch your draw length is over or under the 28” standard.

Using the previous example, if an archer has a 26” draw length and uses a 25” riser with 34# long limbs it will produce 30# of force at full draw OR uses the 23” riser with 34# long limbs it will produce 32#.

This is very important to select limbs that enable you to develop and compete however do not cause long-term physical damage. When purchasing limbs you need to determine if the limbs are too heavy, you can try this simple 7-second challenge.

7-second challenge

  1. Draw the bow to the anchor
  2. Hold seven seconds
  3. Let down without lowering your hands, stay in set-up position to take a 2 sec brake,
  4. Repeat several times.

If you cannot do it properly then the limbs are too heavy for you. If you find this challenge extremely easy, you can look at heavier poundage limbs, if you choose.

Now you understand draw weight and used in combination with your draw length you can see the arrows that match your equipment using a manufacturers arrow selection chart. In the up coming blogs we will try to examine the arrow spine, flex and stiffness.