I wanted to share a spine tester that I just finnished up. It took me several months and 3 pilot testers, but I finaly completed.
The accuracy is dead on using 2216 and 2315's
(http://i750.photobucket.com/albums/xx145/mzombek/photo41_zpsa8e39320.jpg)
(http://i750.photobucket.com/albums/xx145/mzombek/photo3_zpsb0e8f244.jpg)
(http://i750.photobucket.com/albums/xx145/mzombek/photo21_zpsa523ee95.jpg)
Looks nice I was trying to figure out how to zero then I think I saw it on the left side. Curious about weight does it just push straight through from the top, looks as though it would be a pretty consistent design. Good job!!!
Super nice
That looks slick.
Bingo! What a great job! Where do we order?
Simple and elegant. Very nice work.
Nice! I'm working on the same thing - how did you compensate for the return spring in your dial indicator? Do you do it by adding equivalent weight or with your calculations?
Mark
Darin,A bolt with the head cut off to contact the arrow and the thredded end of the bolt into the weight. I tried to use linear bearings and found that as long as the weight sits on the arrow straight,that is all that is needed.
BJORN, How many do you want?
Mark, I was not concerned with the pressure of the spring. I used the 2 pound weight, pulled down on the stem of the indicator. When the weight pushed the arrow as far as it could I gently allowed the indicator to just touch the shaft, did that 3 or 4 times for repetabilty and took that number to cross refference.
Since you are using a 2# weight, does that mean your outside points are 26" apart?
Good job! I paid #200 for my commercially made tester!
Bisch
I like it , been wanting to do one myself too.
Yes, 2# with 26" outside point
I have about 40 bucks in it
Some of you guys are pretty handy "nice work".
I had to part with $200.00 also Bisch
Thanks for posting... I have been shooting wood arrows some lately, I have been contemplating making one.
Nice work, are you making any for sale?
Lucas,
If I get some interest in folks wanting to buy, I could make a few.
I'm interested, let us know price you want?
Bob
Im interested too, let me know how much $
Nice, but way too complicated with a dial indicator like that. And the accuracy is not better than a pointer indicator model either. Problem is, most likely you have to compare the measured deflection in inches to the spine from a table. If you spine any number of shafts, you will soon hate this "feature" of this kind of tester.
Building a good spine tester should take you about 2 hours, another hour is needed to draw the correct scale and about 30min to cast the weights. About 30 dollars worth of home depot materials. I think someday I have to make a tutorial how to build one.
Tecum, I did not build this unit for speed nor did I reference to other spine testers. I checked 17 woodies last night that I purchased from John who owns Twigg archery. I don't know his method, but 15 out of 17 arrows that I checked were the same he got. And you are correct, it will take a little longer than the fixture that you speak of. I made this fixture for the 3 to 4 dozen of shaft that I buy a year. Apparently you test hundreds of shafts at one setting, I do not.
I would like to know a price if you plan on it?
Tecum, who cares if you have to use a chart if need be. What I spine is for my wts and I know what I'm looking for without having to check charts.
And honestly I have more faith in keeping calibration of a dial indicator than something with a needle pointer thingy.
That looks great,Mike,Thanks for posting it!!
Hmm, I actually like it. Simple with no built in design flaws. Good job sir.