Crossbow Nation banner
1 - 20 of 56 Posts

·
Retired
Joined
·
1,755 Posts
Discussion Starter · #1 ·
A lot of folks are starting to get spine testers so they can build their own arrows so I thought I shout throw out a bit of info

1 you should get a 1.94# weight if you want to do spine deflection testing to mat spine

2 you need a 4# weight to properly index crossbow arrows

3 it's best to have hooks on the weight that have bearings to inpart smoothness

4 a .0005 gauge is best to index but you need to also have a .001 to spine match with. You can use the .0005 but you have to Remember and keep it in mind when using the .0005

5 if your dial gauge has an internal spring I suggest removing it

I have found I get more accurate results without a spring
 

·
Premium Member
Joined
·
3,889 Posts
What does the spring look like and how hard is it to be removed?


Sent from my iPhone using Tapatalk
Not hard at all to remove .
Take the back of the gauge off and it is the long spring hooked to the needle I took mine out .easy peasy and yes it works better !!
 

·
Registered
Joined
·
30 Posts
You should give that info to Brian at south shore.Aparently he has forgotten,the last dozen of spinaltapps I received only four of them were marked for stiff side correctly. He says I don't know what to say partner they were indexed on a ram tester
I am probably not the only one who got wrongly spined shafts.I can re do them but I shouldn't have to.
 

·
Retired
Joined
·
1,755 Posts
Discussion Starter · #7 ·
You should give that info to Brian at south shore.Aparently he has forgotten,the last dozen of spinaltapps I received only four of them were marked for stiff side correctly. He says I don't know what to say partner they were indexed on a ram tester
I am probably not the only one who got wrongly spined shafts.I can re do them but I shouldn't have to.

That's Eric, I will talk to him. Send them back to have them redone
 

·
Registered
Joined
·
787 Posts
Yes. It used to have quite a bit of movement before the spring was removed. Now it's a very smooth spin!


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
1,740 Posts
Thanks for the tip about the spring. I’ll be indexing some new shafts soon and will remove the spring before I do .
This place is a wealth of knowledge.
 

·
Registered
Joined
·
8,225 Posts
Deleted
 

·
Registered
Joined
·
8,225 Posts
Not hard at all to remove .
Take the back of the gauge off and it is the long spring hooked to the needle I took mine out .easy peasy and yes it works better !!
What was the intent of the spring in the first place?
 

·
Registered
Joined
·
787 Posts
Can only be used for spine indexing without the spring. Wouldn't work anymore sideways or upside down. The only function of the spring is to pull the feeler back up into the dial gauge.

Sent from my iPhone using Tapatalk
 

·
Retired
Joined
·
1,755 Posts
Discussion Starter · #18 ·
What was the intent of the spring in the first place?
Dial gauges were not designed to test flexible things so they added the spring to hold the shaft against the metal parts being tested

The spring is very light but it will deflect a shaft a few thousandths of an inch. I believe arrow testing is more accurate floating on the shaft instead of flexing it. Now as for crossbow shafts the spring isn't really going to flex them
 

·
Registered
Joined
·
8,225 Posts
I just removed the spring in my .01mm dial indicator (.0003937” graduations) and it seems to return back to the same mark more consistently.

I have a 2nd one in .001” graduations that I’ll do later. (y)
 

·
Registered
Joined
·
3,471 Posts
Now I am wondering if this could be the cause of the inconsistencies I have found from my own tester and factory bought spine indexed arrows..... ?

Would be interesting to see from you who have removed spring to test a few arrows both way (spring in and out) if the dot has moved....
 
1 - 20 of 56 Posts
Top