Safe draw length?

[DC]

I've been thinking too much today . I've got a couple of ideas/theories I would like to check out but they revolve around taking measurements of a bow at or near full draw. If a bow is 40#@28" do you think it would be prudent to hold it at, say, 20" for 3-5 minutes?

[PatM]

Sure, for testing purposes.

[upstatenybowyer]

I guess for me it would be a question of...

What's more important, the test or the bow? 

[DC]

I would use an old bow but I want to compare a lot of bows.

[bradsmith2010]

no I dont think its a good idea,, but if you need to do it,,,that would be up to you,, it may cause more or less damage than I think, I have not tried that,, and dont need to find out,,

[Orrum]

I don't understand???

[willie]

I've been thinking too much today . I've got a couple of ideas/theories

I have been known to suffer from that affliction also....

just out of curiosity, what are you trying to test? I have found ways to make measurements more quickly on my tillering tree

[mullet]

I'm with Willie, Why?

[bradsmith2010]

yes if you want our permission, you will have to tell us why

[DC]

OK I'll try, but I am expecting a bunch of "who cares" and whatnots. I've always thought that the string offset at the arrow pass plays an important part of spining arrows to match the bow. But it was just about impossible to tell where the string line crossed the handle at the arrow pass. After all you can move the string back and forth by just rotating the bow a bit. By changing the angle you look at it you can make any bow look like it has good string alignment. I think you can get close by hanging the braced bow from the string nock and then hanging a plumb bob from the string. Where the bob touches the handle is close to where the string actually crosses the handle. I thought that if I strung a piece of elastic stretched between the "Y" of the loops of the string and then drew the bow to full draw. Now if I sight from the bowstring nock across the elastic to where my sightline hits the handle that will be where the string actually crosses the handle. Measuring from this mark to the arrow pass will be the actual offset.
Well, I tried to explain. Hopefully you can understand even though most of you won't give a ship.

[willie]

If I read your last post correctly, you are trying to compare the degree of "center shot" and how it relates to spine?

As you point out, measurements taken at brace height do not seem have much point of reference.

Have you tried to nock two arrows on a braced bow, one placed on the rest, and the other on the opposite side from the rest,  get a visual idea of the angular offsets?
Maybe even a slow (partial) draw and relax motion to see relative movements?

[DC]

If I read your last post correctly, you are trying to compare the degree of "center shot" and how it relates to spine?

Yes

[DC]

Have you tried to nock two arrows on a braced bow, one placed on the rest, and the other on the opposite side from the rest,  get a visual idea of the angular offsets?
Maybe even a slow (partial) draw and relax motion to see relative movements?

No, but I will

[BowEd]

DC....I don't really totally understand your test there by holding a bow at a 20" draw to see for string alignment.I must be missing your point.
A few things involved with getting the right arrow for the right bow here besides where the arrow passes across the handle.To me it only matters where the arrow is at brace leaving the string.The most important part to me for finding the right spine arrow is the poundage of the bow and the degree of stiffness of the string and how hard the bow comes home to brace after shooting too.The harder it comes home/the stiffer the string the stiffer the spine needed in my experience.
Balancing the braced bow with one tip on the floor holding the other tip loosely to balance.Sighting down the string to make sure each tip has the string running down the tips or recurves or straight limbed bow, where the string goes across the handle that's it.Your eye can only go one place.If it's off the arrow pass 3/16" it is a true centershot.If not the arrows' spine needs to be softer to get around the handle to hit where you are looking.That can be manipulated by canting the bow to a degree too and that will make the windage a non factor also.A centershot is more forgiving and can take a stiffer shaft in my experience shootng either way.Canted or not canted.
That's my understanding of it and I'm sure yours too.Like I said I may have missed the point of your question though.

[Hrothgar]

This is too scientific for me.
As far as leaving a bow pulled to 20" for 5 minutes-if you are at your target weight and the bow is tillered perfectly I've read where this practice can be used to speed up the 'breaking in' process, which will also give the bow any permanent set which is to come.