Spine Tester

Well fast on the back of making a mess of my new arrows and after being seriously impressed with the spining of the arrows from TAC, i set about making a spine tester all of my own. I wanted to adapt the bow press to take the spine tester as the Ratfighter's den is full of motorbikes and i like the modular "one stop shop" idea.
Basically the tester comprises of 2 supporting ends, a centre weight and a dial gauge. The correct distance for the ends is 26" and the centre weight should be 2lbs. this combination provides the industry wide spining standards. I intended to make the ends, floating, as spining is largely irrelevant for us compounders who purchase matched shafts but the 26" gap is a trice too big for Una-Vita spindly little shafts.

I knocked up the ends from 8mm alloy plate utlising 8mm centred roller bearings (£1.25 each)
the 2lb weight was formed from a bl**dy large bolt, fitted with sufficient washers (24) super glued onto the shaft to make the weight up. This was located though to 12mm eye bolts and aligned to my dial gauge directly under. The construction took 20 minutes but numerous problems saw the thing a tad difficult to use. A groove was taken from the weight which allowed the arrow to spin better and served well enough to spine my 4 remaining "old" 3d selects. after trawling through the internet, I think the design would be better served with the dial gauge above the arrow. I have some nylon bar, which i will fashion a foot for the gauge. This means that I will not be able to uses the bow press, so i'm on the lookout for some alloy I beam for version 2. Cost so far, £10.30, although i already owned the dial gauge, (autojumble find at £20 for a quality bit of kit). Not bad for something retailing at @ $230. The bow press i made earlier cost £45 including paint so, it has to be the cheapest pro shop in the country.
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