Bowhunting Tech Tip: Crossbow Maintenance

Crossbows are becoming more and more popular these days, as their use during archery hunting seasons expands across North America. One of the reasons they are so popular is they are easy to become proficient with and easy to use, when compared to vertical compound and traditional bows.

Because they are so easy to use, however, crossbows often times aren’t maintained as diligently as they should be. Like other bows, crossbows have to be maintained in order to get peak performance from them.

In this video, Lancaster Archery Supply TechXpert P.J. Reilly runs down some simple crossbow maintenance practices. He covers checking the limbs and cams for damage, waxing the string and cables and lubricating the rail, among other maintenance procedures.

Before using your crossbow, watch this video to learn what signs of wear and tear to look for, and how to address them if you find them.

How to wax a bowstring and perform other basic string maintenance

Think of your bowstring as the engine that drives your bow, whether it’s a compound, a recurve or a longbow.

To get energy out of the bow to propel an arrow, you must put energy into it. And to do that, you have to draw the string.

Duane Price

Photo by Jeff Sanchez – BowDoc Archery

Your car engine needs regular maintenance to keep up with wear and tear. Same goes for a bowstring.

(And our discussion of bowstrings here includes the cables on a compound bow.)


The simplest thing you can do to maintain your string is to wax it. How often should you wax it? That depends on many factors – humidity, how often you shoot, the presence of dirt, etc.

Basically, you should be able to touch your string at any time and feel a slight tackiness to it. That’s a well-waxed string. If it feels slick and dry, give it a shot of wax.

When you see “hairs” start to stick up from the strands of the bowstring, like the string is getting furry, it’s time to apply some wax. If you see individual strands sticking out, that’s a damaged bowstring, and it has to be replaced.


Here’s a string that needs to be waxed. Notice how the string looks fuzzy.


Here’s the string shown above after it was waxed.

Applying wax to a bowstring is simple. Most bowstring wax comes in a stick, like deodorant. Just rub the stick up and down the string to apply wax, and then rub it into the string by running your thumb and forefinger up and down the string. Use enough pressure so that your fingers heat up. That will cause the string to melt between your fingers as you work it up and down the string.


Applying wax to a string.


Rub your fingers up and down the string to spread the wax and massage it into the string fibers.

When you’re done, there should be no visible chunks of wax.

Do not apply wax to any serving material. The wax can work its way under the serving material, causing it to slide and separate.

Be sure you don’t over-wax your string. This can adversely affect performance.


Closely inspect all of the serving on your strings and cables. Serving is thread that’s tied in over top of the string.

All bowstrings have serving in the nocking area. The ends of strings, where they attach to the cams or the limb tips usually are served. Also, most compound strings and cables have serving anywhere they touch a cam, roller guard or string stop.

You want the serving to sit in tight coils, neatly stacked one on top of the other, on top of your string.

Any separation in the serving in the nocking area must be addressed ASAP. This can affect accuracy.

Slight separation of the serving coils in other places isn’t a pressing concern, but it’s only going to get worse, and it will have to be fixed at some time.


Slight serving separation.

If the serving breaks, it must be fixed no matter where it is on the string or cable.


Broken section of serving.


This is the string shown above after the serving was repaired.

Your local archery pro shop can fix serving issues, or you can learn to do it yourself. Reserving some area on compound bows, however, will require a bow press.

Be aware that serving thread comes in different thicknesses. Serving thickness is most critical in the nocking area, since you want to use whatever thread allows for proper nock fit.


Recurve archers will want to constantly measure their bow’s brace height to check for string stretch. The brace height is the distance between the throat of the grip and the string. Over time, the brace height on a recurve can shrink if the string stretches – especially within the first few days after a new string is put on a bow.

measure brace height

Here’s an archer measuring brace height – the distance from the throat of the grip to the string.

In that case, unstring the bow and add twists to it until the brace height is where it needs to be. Twisting the string will increase the brace height.

On compound bows, archers need to check cam timing to determine if there’s been any stretching of the cables. You want the cams on dual-cam bows to roll over perfectly in synch. If they are out of synch, accuracy will suffer. Twisting a cable will bring out-of-synch cams back together.

If you have a single-cam bow, check with the manufacturer to find out how to determine proper cam position for your bow. The fix for cable stretch still will be to twist a cable.

How to tie a D-loop

In this video, Lancaster Archery TechXPert P.J. Reilly demonstrates how to tie a D-loop onto the string of a compound bow.

The D-loop is attached to the bowstring, to provide both a nocking point for your arrow and a connection for your mechanical release.

You hook your release to the loop before drawing the bow. By doing so, you protect the serving on your bowstring from the wear and tear caused by your release.

Reilly gives a step-by-step explanation and demonstration of the D-loop tying process, which you can imitate at home, and describes the tools you can use to do the job.

Below is an illustration of how to tie a D-loop.


How to change the draw cord on QAD HDX Ultra Rest

The Quality Archery Design (QAD) Ultra Rest is a popular arrow rest used by many archers today.

It’s a full-capture, drop-away rest, that’s triggered by a cord tied into, or clamped onto, the bow cable that pulls down as you draw the string.

From time to time, the rest cord can wear out, or you might want to change it to match your bow’s color-scheme or you might need to change it upon moving the rest from one bow to another.

In this video, Lancaster Archery TechXPert P.J. Reilly shows you how to change the cord on the Ultra Rest HDX.

This process would apply to most of the new QAD Ultra Rests. Some older models, as well as the current Hunter and LD Pro series rests, have a slightly different construction, and so this video can help guide you in changing the cord on those rests, but the process is not exactly the same.