Paper Tuning

[pwiles1968]

Anyone tried paper shoot through tuning for compound bows, I know it is not the be all and end all WRT tuning just interested in opinions and experience.

[Marcus26]

Paper tuning is useful, but not in the way most people think.
Up-down tears indicate a high or low nocking point
A left-right tear indicates either poor centreshot. If moving the centreshot does not change the tear then it is likely hand torque. Get a good shooter to try also in this case.
It can show up other issues in teh cam areas as well, but this is rare.

It won't show arrow spine.

Originally Posted by Marcus26

Paper tuning is useful, but not in the way most people think.
Up-down tears indicate a high or low nocking point
A left-right tear indicates either poor centreshot. If moving the centreshot does not change the tear then it is likely hand torque. Get a good shooter to try also in this case.
It can show up other issues in teh cam areas as well, but this is rare.

It won't show arrow spine.

Marcus, will paper tuning show up a weak or stiff arrow? is there such a thing as a stiff arrow with compound?

[Marcus26]

No it won't show a weak or stiff shaft, you need high speed video for that.

[geoffretired]

Using bare shaft tuning, I noticed that the softer spines shoot left and stiffer ones go right. This is the reverse of what you get with recurve shooting.
If you suspect the spine is wrong, altering the poundage will indicate the direction to go in.

[Marcus26]

I have shot bareshaft ACE's ranging from 720 up to 430 and put them all in the 40cm 10ring at 18m.
Bareshaft testing on a compound is useless.

Remember, compound arrows don't flex left-right due to spine.

[joetapley]

There's an old story (which if I sort of remember) involves a philosopher, a physicist and a mathematician travelling on a train to Scotland and through the window they see a black cow standing in a field.

The Philosopher says "Look - cows in Scotland are black!".
"No" says the Physicist "Some of the cows in Scotland are black"
"No" says the Mathematician "In Scotland there is one field in which there is a cow which is black on one side"

The moral is that one needs to be careful about what conclusions you reach from observations or experiments.

Originally Posted by joetapley

There's an old story (which if I sort of remember) involves a philosopher, a physicist and a mathematician travelling on a train to Scotland and through the window they see a black cow standing in a field.

The Philosopher says "Look - cows in Scotland are black!".
"No" says the Physicist "Some of the cows in Scotland are black"
"No" says the Mathematician "In Scotland there is one field in which there is a cow which is black on one side"

The moral is that one needs to be careful about what conclusions you reach from observations or experiments.

I like that one Joe! Something we can all forget sometimes

Soz it won't let me give you any rep points

[geoffretired]

Thanks Marcus and Joe, I'm clearer on that now. It makes good sense. Can you throw some light on the situation when the bare shafts go to one side of the fletched groups? Does that happen as the result of torque issues or centreshot or something I've not mentioned? Several archers I know use bare shafts. They start off getting the nocking point sorted and notice the bare shafts are always one side. In the past I've said it was spine or torquing the bow( I won't mention spine from now on). If it's not torque, I don't want to carry on saying that either.
Thanks
Geoff

[joetapley]

Geoff

Historically (as far as I know) there have been two suggestions put forward as to what this "tuning" thing essentially is. The first suggestion was by Don Rabska in the Easton Maintenance/Tuning Guide. The suggestion was that it was to do with the launch alignment of the arrow i.e. you tried to minimise the airflow angle of attack on the shaft at launch. The second suggestion was put forward by me several years ago. I hopefully showed that while the arrow launch alignment idea was going in the right direction it didn't really "fly" and the underlying issue of tuning was to do with the rotational energy that the arrow had at launch. This concept mechanically/aerodynamically agrees with "tuning experience" as regards explaining how the various tuning methods work, why tuning is a function of target distance and predicts that tuning is also a function of wind (the latter idea according to the Heretic Archer has now received some verification by testing).

If you understand the mechanics/aerodynamics of arrow flight behaviour it becomes obvious why with a compound bow at 18m that whether shooting X10s or broom handles all the arrows will go in the ten ring. It does not discredit the bare shaft tuning concept.