Paper Tune Root-Cause Diagnostic

A tear is just the arrow leaving the bow with some yaw — the nock end and the point end aren't travelling in exactly the same line. What puts that yaw there varies a lot: the nock pinching or slapping off the string at release, the rest sitting off the arrow's true center line, the nocking point set too high or low, a cam leaning or coming out of time on a compound, grip torque steering the riser at the shot, something physically clipping the vane or a cable on the way out, a bent shaft or an insert seated crooked, or the shaft being outside the bow's real spine window. The tear itself doesn't say which — it only says a yaw exists. That's the whole reason this tool exists instead of just reading a chart.

Direction tells you the plane the yaw is in — horizontal or vertical — and horizontal tears share a short list of usual suspects (center shot, cam lean, grip torque) while vertical tears share a different one (nocking point height, nock pinch). But more than one of those can produce the same-looking tear, and reading direction alone can't tell a center-shot problem from cam lean, or a nocking-point problem from nock pinch. What separates them is what happens when you actually test each one — which is why this tool asks about your rest-move result and three free mechanical checks, not just the tear.

Nock pinch is the string groove gripping the nock too hard, so instead of releasing cleanly it kicks the tail sideways or vertically for a fraction of a second after the string separates — after the arrow is already committed to a flight line the fletching then has to fight. It shows up mostly as a vertical tear (nock high or low) that won't fully close no matter how much you move the nocking point, because the nocking point was never the actual problem. Check it by feel: the nock should seat on the string with a light, even click, not a hard squeeze and not a loose wobble. A too-tight nock is a common, quick-to-fix cause that a lot of paper-tuning advice skips straight past on the way to the rest.

Yes, and it's one of the more argued-about causes in tuning threads precisely because it looks identical to a center-shot problem on paper — both put a horizontal tear in the sheet. The giveaway is what happens when you try to fix it with the rest: a center-shot issue closes up within normal rest travel, while cam lean keeps producing a tear (or a tear that won't fully close) even after the rest has run out of reasonable adjustment, because the string itself is tracking off to one side at the cam. That's a draw-board and cam-timing fix, not a rest-position fix, which is exactly why this tool treats "the tear didn't change after several small rest moves" as a real signal rather than just telling you to keep moving the rest further.

Three checks, none of which cost anything: spin the arrow on a spinner or across two field points seated in a scrap of 2×4 and watch the tip against a fixed mark — a tip that traces a circle is a bent shaft or a crooked insert, not a tuning problem. Dust the vanes and rest with foot powder or lipstick and shoot one arrow — a clean wipe across a launcher arm or cable makes a tear no rest position will ever close. Shoot a few arrows with a completely relaxed hand and a wrist sling — if the tear changes or shrinks, the bow was never the actual problem. All three take a few minutes and rule out things a rest adjustment structurally cannot fix, so they're weighted heavily in the ranking below.

Because the tear alone is one data point and the rest-move result is a second, independent one — and two data points rule out far more than one. A tear that closes cleanly after a couple of small rest moves is very likely a center-shot or nocking-point issue, plain and simple. A tear that barely shrinks, or doesn't move at all after several moves, points somewhere the rest can't reach — spine, cam lean, or a mechanical fault. Treating those as the same situation is how people end up chasing a rest position for a problem the rest was never going to fix.

For a finger release there's a published reading: Easton's tuning chart treats a nock-right tear as stiff and a nock-left tear as weak for a right-handed archer, so the recurve/longbow option shows it, mirrored for left-handed shooters. For a compound shot with a release, experienced tuners argue that a horizontal tear is a center-shot signature first and says little reliable about spine, and that disagreement shows up in the same tuning threads year after year. What isn't in dispute is the behavior: if a tear won't close after several correctly-directed small rest moves and every mechanical check comes back clean, spine is a genuine suspect worth checking against a manufacturer chart with your real draw weight, draw length, point weight and cut length.

Fix in the order the tool ranks them, one change at a time, and shoot paper again after each one before touching anything else — changing two variables at once is how a correct fix gets missed or credited to the wrong cause. If spine comes back as a suspect, run your real numbers through the Dynamic Spine & Shaft Flex Calculator before buying shafts. Once the tear is clean, the Broadhead Flight & Tuning Stability Checker shows what any remaining yaw would have cost you downrange with a fixed-blade head on.

With fingers, the string rolls off the fingertips and the shaft flexes around the riser, so a horizontal tear is read as a spine reaction first. Easton's tuning guide says that for a right-handed finger shooter a nock-right tear is a stiff arrow and a nock-left tear is a weak one (mirror it if you shoot left-handed). The levers before a new shaft are plunger spring tension, point weight, brace height and draw weight, and a higher brace height makes the arrow shoot weaker. The nocking point also starts higher, about 1/2 in above square for fingers against about 1/4 in for a release.

You log the starting tear, then one change per round and the tear it left. The log fills in the rest-move answer for you, flags a tear that flipped sides, grew, or hasn't shrunk after three moves on the right plane, and, once two rounds used the same adjustment and the tear is shrinking, estimates how many more steps should close it. That estimate is a straight line through your own numbers, not a formula, because no published source gives a fixed ratio between rest travel and tear size.

Step back 6 ft and shoot paper again, then run a bare-shaft planing test at 15 to 20 yards: three fletched arrows, then two bare shafts at the same aim. Bare shafts high or low mean the nocking point moves toward them. After that, shoot broadheads against field points at your hunting distance; a vertical split goes to the nocking point and a horizontal one to the rest or plunger.

Partly because the arrow is still flexing when it reaches the paper. Run typical compound hunting builds through the planner below and they flex roughly 70 to 85 times a second, so at 255 to 300 fps one flex cycle covers only about 3.5 to 4 feet of flight. Two papers half a cycle apart catch the flex going opposite ways, so the tear can shrink, grow or even flip without anything on the bow changing. The whole-arrow nose-left, nose-right swing that fletching corrects changes much more slowly, over tens of feet. The Paper Distance Planner on this page works out the flex cycle length for your own arrow and speed, and suggests a second paper between 10 and 15 feet that sits a whole number of flex cycles from the first, so the flex part of the tear looks the same at both.