Before you start

The string is held at 100 lb of tension on the building jig — the same measurement load used throughout the build. The bundle has already been burnished and settled. The nock area of the bundle is clean, waxed, and free of stray fibers. The serving jig is threaded, tension is set, and the serving material spool is oriented so the serving lays flat against the bundle — not on edge.

String tension while serving. 100 lb. Not the 200 lb burnishing load, not the 300 lb final stretch load, not brace tension. Serving is done at the same 100 lb the string is measured at, so the served bundle geometry matches the geometry it was spec'd to.

Decide the length of the served region before the first wrap. Mark it lightly on the bundle with a soft pencil or a piece of tape. Overshooting is easy. Undoing wraps to shorten is not.

Serving direction — against the twist

Before the first wrap goes on, decide which way the serving will travel around the bundle. This is not a stylistic choice. The serving must wrap in the direction opposite to the helical twist of the bundle underneath it.

The bundle, after twisting, is a right-hand or left-hand helix depending on which direction it was twisted on the jig. The serving wraps around that helix. If the serving is laid in the same direction as the twist, every wrap of serving nudges the bundle in the direction of more twist — or, worse, it lifts along the strands and slides. If the serving is laid against the twist, every wrap of serving crosses the strands at an angle, bites into the bundle, and locks the twist in place instead of adding to it.

The rule. Serving direction is cross to the bundle's twist. If the bundle was twisted clockwise (viewed from one end), the serving wraps counter-clockwise from that same end. If the bundle was twisted counter-clockwise, the serving wraps clockwise. The two helices cross each other.

The check is visual. Sight down the length of the bundle before serving and note which way the strands spiral. Then set the string on the jig so the serving material will lay in the opposite spiral. If the serving looks like it is following the strands, stop and reverse the string. If it looks like it is crossing them at an angle, it is oriented correctly.

A serving laid in the wrong direction will feel fine going on. It will fail in service. The bundle will unwind against the wraps over the first few hundred shots, the serving will loosen, the D-loop will start to shift, and the peep will rotate. There is no fix short of cutting the serving off and redoing it.

Starting the serving

Two methods. Both work. Pick the one your jig supports cleanly.

Method 1 — Trapped tag start

  1. Pull 6 to 8 inches of serving off the jig as a tag.
  2. Lay the tag along the bundle, running in the direction the serving will travel.
  3. Begin wrapping the serving over the top of that tag. The first turn traps it. The next 8 to 10 turns lock it in.
  4. Keep the wraps tight and touching. No gaps. No overlaps. Once the tag is fully buried, either trim flush under the remaining serving wraps, or pull the tag back, cut it, and burn the end. The pull-back-and-burn method leaves a small plug that adds a mechanical stop against slippage.

This is the cleaner start. The tag disappears completely inside the wraps and the beginning of the serving reads as a single, uniform edge.

Method 2 — Half-hitch start

  1. Tie a single half hitch of the serving material around the bundle at the start point.
  2. Snug it against the bundle with hand tension. Not tight enough to crush fibers.
  3. Begin wrapping normally from the hitch.

Faster to set. Slightly less clean at the transition. Fine on cable serving or anywhere the start is not visually critical. On a center serving, prefer the trapped tag.

Which to use. Trapped tag for the serving. Axial never uses half-hitch methods.

Serving tension

Serving tension is set at the jig, not by hand. The jig applies constant, repeatable pull on the serving material as the string turns beneath it. Hand pressure introduces variation; the jig removes it. If the jig can't hold consistent tension, fix the jig before serving the string.

The target: firm enough that the serving beds slightly into the bundle and does not slide under thumbnail pressure once finished. Not so tight that it deforms the bundle or squeezes the strands out of round. Most builders will not serve tight enough on the first attempt.

Feel check. A correctly tensioned center serving looks tight and uniform, feels solid to the thumbnail, and shows no visible gaps or high-and-low turns. If you can push individual wraps sideways with a fingernail, the tension is too low. If the bundle underneath is visibly pinched or hourglass-shaped, the tension is too high. You can sometimes measure it: the outer diameter of the served section changes with tension.

Different jigs and different serving materials will read slightly differently on the tension dial. Halo, 62XS, and Powergrip do not all pull at the same setting for the same finished look. Do a short test length on a scrap piece of the same bundle count before serving the actual string, and calibrate the dial to that. 3D notoriously requires additional tension.

End serving direction

End serving can be a challenge. The overlap at the junction between the end serving and the end-loop serving is a real indicator of build quality. The technique is: serve toward the end loop, then back-serve. That combination sounds easy but is a real challenge in limited space — it is possible to wrap the back-serve material around the steel post rather than around the Y of the end loop, and that is a defect that is hard to spot until the string is on the bow.

The back-serve finish

The back-serve is what locks the end of the serving without a knot. Done right, it is invisible from the outside and mechanically as strong as the rest of the served length. It will appear and function exactly the same as the trapped-tag start.

The idea is to give yourself additional material to "undo" as the wraps go on, so the finishing tag can be pulled back through the last section of serving.

  1. Stop about 8 to 10 wraps short of the finish point. Don't serve all the way to the end.
  2. Lay a pull loop along the bundle with the closed end pointing back toward the served section and the open end (the two tails) pointing forward, in the direction the serving is still traveling.
  3. Continue serving over the top of that loop for the remaining 8 to 10 wraps. The loop is now buried under the last section of serving, with the closed end sticking out backward and the open end sticking out forward past the finish.
  4. Cut the serving from the jig, leaving a 6- to 8-inch tag on the string side.
  5. Thread that serving tag through the open end of the pull loop.
  6. Pull the closed end of the loop backward — the direction it was pointing when you buried it. The loop pulls back through the wraps, dragging the serving tag with it, tucking the tag under the last 8 to 10 wraps.
  7. Trim the serving tag flush where it exits the wraps. It will not pull out. The wraps clamp it in place.
Why it works. The back-serve traps the tag under the same wrap tension that holds the rest of the serving on the bundle. There is no knot, no bulge, and no failure point. The finish is as strong as the middle of the served length.

Common back-serve failures

  • Loop too short. If the pull loop is shorter than 6 wraps, the tag doesn't get enough grip and can slide out under load. Use 8 to 10 wraps of coverage.
  • Loop material too weak. The loop has to survive being pulled back through the wraps under significant friction. A single strand of serving thread is not enough. Use a folded loop or dental floss.
  • Pulling the loop the wrong direction. The loop pulls back the way its closed end is pointing. If you buried it with the closed end pointing forward, you'll pull the tag out the wrong side and it won't lock. Check orientation before the last wraps go on.
  • Trimming the tag before pulling it through. Do not trim until the tag is fully seated. Once it's under the wraps, then trim flush.

After the serving is finished

Bring the string up to the 300 lb final-stretch load and check the serving under that load. Look for:

  • Any wrap that has migrated or opened a gap.
  • Any section where the underlying bundle looks pinched or distorted.
  • The two ends of the serving. Both should sit flush against the bundle, with no fuzz, no lift, and no visible tag.

If the serving passed those checks under load, it will hold through the D-loop install, the nock set, and the archer's service life. If it did not, cut it off and re-do it. A center serving is fast to replace on the jig and expensive to replace after the string is installed.

Published 2026-07-04  ·  Axial Bowstrings