Measure

How to measure almost everything on your bow.

String length

If you have been able to really get to know how your bow performs best and fine tune your brace height, you might want to get more specific about the length of your string. Also if you prefer a certain number of twists in your string, it may also be necessary to customize your string length beyond the manufacturer recommendation. Here's how to measure your string to get the same length for your next string.

What you will need:

A tape measure
A bow stringer (to remove your string from your bow)
A nail in a fixed location (or a friend to hold one end)

How to measure:

Remove your string from your bow
Hook one end of your string to a fixed point, such as a nail (or have someone hold it for you)
While leaving all the twists in your string, measure from loop tip to loop tip with just enough tension to keep the string straight

This string length can be duplicated in your next string! Just provide that measurement with your order.

Note: This method is not reliable when measuring a Dacron or flemish twist strings.

A note on AMO* measuring specifications: Some string makers will make your string to a specified length under 100 pounds of tension. That's great if every customer has the means to be able to measure their string under 100 pounds of tension. Since that is not typically the case, we prefer the above method as it is more accessible to archers.

*Archery Manufacturers Organization which is now the ATA (Archery Trade Association)

Length recommendations

Here are the string length recommendations from bow manufacturers:

Brace height

The brace height is the distance from the pivot point of the bow to the string at rest.

Your string will come with twists in it. You can customize your brace height by:

adding twists shortens the string and increases the brace height
removing twists lengthens the string and decreases the brace height

Most manufacturers have a recommended brace height range but you can work with your coach to fine tune this setting. Once you set your brace height it's important to keep the twists and not let the string unwind (losing twists) when you unstring the bow. Make sure to secure the end loops together to prevent losing twists when the bow is disassembled.

The best way to keep your brace height consistent is to make sure you don't lose twists when taking down and setting up your bow. There are a couple different ways to do this:

Loop the end loops together
Clip the loops

Recommendations

Each manufacturer recommends a brace height range for their bows. Here's a summary of those recommendations:

Riser

If you want to verify the length of your riser you can measure the overall length.It's usually an odd number and the lengths are in 2" increments. Standard riser lengths are 23", 25", 27". While there are other sizes out there these are the most common.

Limbs

Limb length can be a bit confusing as there are 2 different ways they are labelled. The common lengths are:

short (or 66")
medium (or 68")
long (or 70")

While some manufacturers use short, medium, and long on their labels, others mark limbs with an overall bow length measurement in inches that assumes they will be used with a 25" riser. That's not to say those limbs can only be used with that length riser, but that's just how they label them. Those limbs will be labelled as 66", 68", 70".

The sample limb labels shown here all represent 28 lb medium limbs. Some include the overall bow length and draw weight if they were used on a 23" riser also.

Overall bow length

For single piece bows or to just to verify the length of your setup, sometimes it helps to measure the overall length of a bow. Here's how that can be done:

Unstring the bow and lay it on a flat surface.
Measure from string groove to string groove. Follow the curvature of the limbs but go straight over the riser.

Measuring tips:

If you don't have a flexible tape measure, try laying down a piece of masking tape or painters tap along the bow. Make a mark where the string grooves start. Then pull off the tape, stick it to a flat surface, and measure with a metal tape measure between the 2 marks.

Chart

Here is a general guide for determining bow length:

Related article: See How to order a custom string

Center serving

Here's how you can customize the measurement of your center serving length and position for your next string. The first step is to measure your current string.

Here's what you will need:

Your current string
A tape measure
A piece of tape (blue painter's tape works well)
A marker
Pen and paper to make notes

1. Find the center of your string

Keep in mind that the nock set is not usually the center. Start by taking the string off the bow. You can use one of 2 methods to find the center:

Fold the string in half. Try not bend the center serving.
Measure the overall length of your string and divide by 2.
You can use a piece of tape to avoid marking your string. Use a marker to draw a line exactly in the center of the string on the tape.

2. Measure above the center

This will be the length above the center mark, measured in the direction of the top (larger) loop. Notate that measurement in inches.

3. Measure below the center.

This will be the length below the center mark, measured in the direction of the bottom (smaller) loop. Notate this measurement in inches.

Send along those measurements with your next order to get the exact center serving you would like.

End Loops

Strings are built with 2 different size end loops. The large loop goes on the top limb and the smaller goes on the bottom. This is designed so the large upper loop can slide down the length of the limb when unstringing the bow.

Sometimes archers prefer to customized the size of these loops for particular limbs. This can be done by specifying this measurement. Each loop can be measured from the outer edge of the loop to the point where the loop comes together.

End Serving

The purpose of the end serving is to add a layer of protection between the limb and the bow string material. Ideally this serving well extend a little past where the string makes contact with a recurve limb. For most recurve limbs that is about 6". We usually do 4" for longbows and longer for super recurve limbs as the contact area is even longer for those limbs.

This measurement can be customized if needed. It is measured from the tip of the loop to where the end serving ends.

Nock fit

There are 3 things to test nock fit:

When you have a good nock fit, that is one less thing to worry about in your tuning and shot process.

1. You should be able to slide the nock up and down the center serving (in an area where the nock set is not tied in).

2. You should NOT be able to rotate the arrow when it is clicked onto the center serving.

3. When you pull the arrow it should disconnect from the string when pulled 1/2". This can be tested by:

Place your bow square on your bow and see where your plunger button is on the ruler
Nock an arrow facing away from your bow
Pull the arrow and see how far it goes before disconnecting from the string (watch the ruler and the plunger button as you pull)
This distance should be about 1/2"

Note: Not all nocks are created equal. Some nocks need to be tighter on the string (#1) to create the same release (#3) as nocks that are looser on the string for that same release.

Related article: See How should my nocks fit?

Nock set

It's important that the nock set location be documented so it can be set the same when you set up a new string on a bow. Here's how to notate this measurement.

Start by snapping your bow square onto the string and line up the bottom of the square on the arrow rest. (Some prefer to line up the bottom of the square with the bottom of the plunger button. That works too, but just make sure you do it the same way every time.)

Now look at the bottom of the top nock set (the upper red line in the illustration). See how far above the 0 point (bottom red link in the illustration) the nock point is set. This is the nock elevation.

If you are enjoying all this measuring, you should really check out Archery Path. There is so much more to measure!

Archery Path is an online tool that allows you to input all your measurements and then be able to try out various scenarios to get the best tune before making any changes to your actual bow. It's much cheaper than cutting arrows too short. And they also offer seminars. Highly recommended and OCD-approved!

Check it out