TSBI Tech · Bow Challenge · sourcing in Canada · listings checked 9 Oct 2026

Bow Challenge Parts List

Everything needed to build the bow-lift rig shown in the 3D simulation, with a suggested listing for each part. Spec comes first: if a listing is out of stock, any product that meets the spec works. Fabricated parts need a quote from the local vendor.

What the indicator must do for our software

Accept one 4-wire or 6-wire 350 Ω strain-gauge load cell at 2 mV/V.
Stream readings continuously, without a request, at 10 readings a second or faster.
Serial: RS-232 (DB9) or USB virtual COM port, 9600 8N1 or configurable.
Plain ASCII frames with a stable or unstable flag, e.g. ST,GS,+0042.6,kg. We need the frame format from the vendor's manual before we write the parser.
Front-panel zero (tare) and span calibration with a known weight.
Resolution of 0.1 kg or better across 0–300 kg. Runs on 120 V AC.

Safety requirements for the fabricator

Every extension spring gets a safety cable through its centre. A spring that breaks without one can whip across the stage.
A travel-limit chain runs alongside the springs, so the bow cannot rise past chest height however hard someone pulls.
All rigging (shackles, turnbuckle, chain, anchor) rated at a working load of 1,000 kg or more. That is more than 3× the strongest expected pull.
Anchor plate bolted or welded through the base plate. The participant stands on the plate, which also holds it down.
Bow prop under about 8 kg, with no sharp edges at the tips. Grip diameter 35–45 mm.
Load cell mounted in straight-line tension only, with no side load.