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Main Boards => PowWow => Topic started by: AALLFAB on January 07, 2010, 10:15:00 PM

Title: HOW 2 Callibrate an Arrow Spine Tester??
Post by: AALLFAB on January 07, 2010, 10:15:00 PM
How can I tell is this spine tester is up to accurately measure spine close to accepted standards. I just made it and it is so cool but I cant figure out how to attach a photo directly to this message.  It is a way cool looking direct pressure over a gauge style. Jim
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: Fletcher on January 07, 2010, 10:41:00 PM
Check it with some Easton aluminums.  They are very consistent.
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: SCATTERSHOT on January 07, 2010, 11:12:00 PM
2016 = 60#
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: luv2bowhunt on January 07, 2010, 11:22:00 PM
Jim, send me the pix to kwaite@bit-stream.biz and I'll post them for ya... I'd love to see it myself  :D

Kevin.
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: AALLFAB on January 08, 2010, 12:04:00 PM
(http://i985.photobucket.com/albums/ae340/aallfab/SPINE%20TESTER/100_6981.jpg)
(http://i985.photobucket.com/albums/ae340/aallfab/SPINE%20TESTER/100_6980.jpg)

This is a test of uploading photos of the spine tester. Jim
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: Earl Jeff on January 08, 2010, 12:54:00 PM
I took a few Different arrows that I already knew the spine weight and use them to adjust the anvil weight on my spine tester
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: luv2bowhunt on January 08, 2010, 05:50:00 PM
That is sweet looking!! What did you fabricate that out of and what do you use for the weight?
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: AALLFAB on January 08, 2010, 06:07:00 PM
I didnt show the weight because it is a little embarrassing compared to the acrylic craftsmanship on the tester and the cool antique Starret indicator. It is a long bolt with various mis matched metal spacers and washers and a hose clamp to keep them from sliding off at exactly 2# total. Jim
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: MercilessMing on January 08, 2010, 06:51:00 PM
What a beautiful tester.

Rose City has an AMO spine chart as:
http://www.rosecityarchery.com/AMOspine.html

From my experience the spring loaded rod from the dial indicator may change the reading of displace depending since the shaft is not that rigid.  You will need to zero out the effect by manually relieving the loading from the rod to the shaft.  After then, the reading will be more accurate.
Title: Re: HOW 2 Callibrate an Arrow Spine Tester??
Post by: AALLFAB on January 08, 2010, 08:01:00 PM
Yep. At first i added 3 ounces to the weight to counteract the dial spring. but since the spring varies in pressure as it is compressed this was not the ideal solution so went back to 2 pounds and i do as you suggested. As it is i am confident i am within 2 pounds on correct spine and i will know better when i learn from someone the spine variance in easton aluminum shafts. Jim