Primitive Archer
Main Discussion Area => Arrows => Topic started by: islandpiper on September 20, 2009, 05:34:02 pm
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I just gotta brag a little....... Here's my new "Jim Hill Sorta" spine tester. I need to cast a 2# test weight and it will be done.
(http://i498.photobucket.com/albums/rr346/islandpiper51/DSCF0002-2.jpg)
Mostly just leftover scrap materials except for the Dial Indicator which was contributed to the project by Ian_Johnson's dad. (Thanks buddy!)
piper
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I like it :)!
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so when can i expect my first dozen shafts? ;D
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Trey..........advice from an old guy: get a job, look at your pay stub, you'll get the shaft every pay day!
Soon as i cast the two pound weight and get to weigh it ACCURATELY i'll cut some ash shafts and plane them up. Been a little busy caring for my wife and running a business. I wish i had home work like you do , i'd work shorter hours.
piper
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lol. i hear that. its just fun to poke the ole bear with a stick sometimes.
btw im lookin for a job. not exactly easy to find when your new town consists of 2 service stations and a mom and pop gorcery. >:(
i been wanting to learn to make cane arrows. i may be swinging in after you get it done to test some shafts.
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Very cool, i have been really wanting to build one like that. I had some poc shafts given to me so i put that project on hold. Yours looks nice. BTW they have dial indicators cheap at harbour freight tools.
Mike
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If you are going to be making hardwood shoot or cane arrows make one of the uprights adjustable to accomidate the irregular surface of these materials.
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Hey 'Pipes? Could you post the dimensions and such, I think more than a few of us would like to copy that handy li'l tool?
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Hey guys, glad you like it. Here's the link. the inventor used lots of metal. I have a wood shop. Yup, my dial indicator is from Harbor Freight, a gift from Ian Johnson's dad Our Harbor Freight is about 35 miles from here. That's cool.
I have the lead on hand now. Just need some time to make up the two pound push-weight
piper
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Trey..........advice from an old guy: get a job, look at your pay stub, you'll get the shaft every pay day!
;D ;D ;D
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mr. keith, is yer link one of them new invisible ones?
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Piper, Here is my version of a James Hill spine tester, also made with scrap wood. As per Art Butner I used a large diameter bolt for the weight. As you can see it pushes down through eye bolts rather than pulls down like a suspended weight. I'm not sure if the direction of deflection matters or not. ::) Also from Art, the adjustable upright. The one on the right has a slot in the wood where the bolt goes through and a wing nut for quick adjustment. I think I got my dial indicator from Grizzly.
The drop bolt weight has a copper plumbing sweat fitting forced over the hex head with lead added inside to make up the 2#. I weighed the components using lead shot until I had the 2# then melted the lead shot and poured it into the copper fitting.
I used skateboard bearings for the arrow shaft to rest on when spine testing.
I also have a suspended weight that I use. It is a small metal PVC pipe cleaner can with a cup hook in the lid. I added lead shot to it to make up the 2#.
(http://i5.photobucket.com/albums/y199/PatBNC/spinetester001.jpg)
(http://i5.photobucket.com/albums/y199/PatBNC/spinetester002.jpg)
(http://i5.photobucket.com/albums/y199/PatBNC/spinetester003.jpg)
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http://www.jamesmhill.com/Spine_Tester.html
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I guess the bolt was Hill's idea. ;D I couldn't get enough washers on my bolt to make weight so I went with the copper fitting and lead shot. Actually having the bolt come down directly over the dial indicator would give a more accurate reading than a weight that is hung off center.
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I have one similar to Pat's although I went the washers on the bolt route. As far as adjustable I put two wood screws in the notches where the arrow rests, on both sides. Also, because I spine unstraightened bamboo shafts I have the dial indicater on a swinging arm kinda thing in case the shaft bows out I can still move the indicator under the shaft to get a truer reading.
possum
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whats he purpose of the chart?
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Great work everyone. I have to make me one of those real soon...
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The chart is to convert the arrow deflection to pounds of spine weight.
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sorry, but i need a little more laymans terms. i'm still new to arrow building
\
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A spine tester shows how much deflection(bend) an arrow has with a 2# weight hung from it. That deflection coincides with with a spine weight on the chart. example, .578" deflection means the arrow is spined for45#, .473" for 55# spine, .400" for 65# spine, etc