Bow press and draw board for compound: Anwar 2026

An Indonesian group built a device that combines a bow press and a draw board in a single rigid frame, with load cells and digital gauges that read draw weight and draw length while the bow is being worked on, and had it used for four weeks during the ordinary training sessions of university compound archers at Universitas Negeri Makassar.

Only one number is published. A "string precision score" rises from 71.3 ± 2.22 before to 85.7 ± 2.35 after the four weeks, an average increase of 20.1%, with p = 0.002 on a paired-samples t test and an effect size of d = 2.48. The comparison covers six archers, measured before and after, with no group that did not use the device.

Everything else in the paper is descriptive. The coaches rated the system as safe, functional and useful for training on a Likert-scale questionnaire, and the observers report steadier posture, a smoother release, tighter groups and less cam misalignment over repeated draws. None of those impressions comes with a figure: the paper reports no scores, does not measure group size, and does not say what changed on the target face.

The work presents itself as engineering research and development: needs analysis, technical review, CAD design with a finite-element check on the frame's stiffness, construction of a prototype and laboratory testing. The experimental part uses the simplest possible design, one group measured before and after, with no control group and no randomisation.

The device is a mechanical frame with adjustable jigs, pressure sensors and digital gauges reading in real time; draw force comes from a load cell and draw length from a linear displacement gauge. The questionnaire for coaches and athletes was reviewed by two archery experts and one mechanical engineering lecturer. Before testing, participants completed a short physical activity and readiness questionnaire. The sessions took place in the faculty's sports science laboratory, which has a shooting field, strength facilities and biomechanical instruments, and three certified coaches supervised them.

On the sample the paper contradicts itself: the participants section gives fifteen athletes, the results six who completed both measurements. The more serious gap concerns the measured variable. The "string precision score" is never defined: the paper does not say what scale it sits on, what the instrument reads, who assigns it, or how many attempts produce it.

The main limitation is that we do not know what was measured. Without a definition of the string precision score, the move from 71.3 to 85.7 cannot be translated into millimetres, into pounds, into cam synchronisation or into any other quantity an archer would recognise. The number stays internal to the paper.

Other limitations pile up around that one. There is no control group, so four weeks of ordinary training remain mixed in with use of the device. Six participants were analysed, and an effect size of 2.48 computed on six people says very little about archers in general. Shooting accuracy, which the abstract lists among the aims, is nowhere measured: the tighter groups are a visual judgement by coaches who knew which phase of the work they were watching.

The text also shows signs of light editorial review. The conclusion contains a truncated sentence ("1% in string precision after one month"), the introduction cites an "Author, 2023" and an "Author, 2024" that were never replaced, and at least one reference carries a DOI that looks like a placeholder. The published title misspells "Compound". The venue is flagged as regional in the registry. None of this makes the data useless, but the result should be read knowing how little supports it.

For a compound archer this record is worth having because it shows that something has been published on a home-built tuning rig, not because it helps decide how to tune. What the paper documents is that a press combined with a draw board, fitted with a load cell and a displacement gauge, can be built and used in a university setting, and that the coaches who tried it found it safe and convenient. The rest is thin: the 20.1% gain refers to an index the paper does not explain, and no score, no group and no distance on the target face was recorded.

So there is nothing here that says how much cam synchronisation is worth in points, what tolerance is acceptable, or whether measuring the draw-force curve on a draw board changes results in competition. The study does not really address cost either, beyond noting that professional presses are expensive and that many archers in Indonesia rely on improvised tools. It stays in the registry as a trace of an almost empty line of work, the testing of compound tuning equipment, not as support for any claim.