I went all round making various spine testers, never really happy with any, (but then I don't have KidCurry's engineering skills) so I ended up buying one of the Bearpaw arrow analysers. This plugs into a computer and weighs/spines and measures straightness, and keeps a record of the values for each arrow.
I make a lot of arrows, especially wood shaft, both for myself and about a dozen other archers, so measuring spine and weight, so I can batch select shafts, is important. I don't want to make arrows with shafts that are supposed to be say 30-35 spine as bought, but usually spine from 28-38, I want to get them into batches that are within 1 spine and 5 grains weight. I usually buy 12 dozen shafts at a time so I can batch them into say 10 sets of twelve with a couple of dozen canes for the garden left over.
I shoot both Trad (Hunting Tackle) field and target
longbow to a fairly high standard (MB at both) and yes being this fussy does make a difference.
This is probably about half of my arrows!
Arrow analyser, bend the arrow until it touches the stop.
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