Force/Draw Curve Question

[The Gopher]

Recently I have been plotting a few force draw curves on some of my bows to see how they compare. There is one small thing bothering me though, should the draw length be measured in a different manner than the “normal” method?

Lets take a bow with a 6” brace height and a 1.5” deep handle section. The normal method of measuring draw length is to measure to the back of the bow which means that technically the above bow, just sitting at brace is also being drawn to 7.5”, of course it really isn’t its just sitting there, but you see the dilemma for plotting a F/D curve.

My guess is that to get a true representation of the energy storage you need to measure the “true” draw length of the bow. That is, if a bow has a 6” brace height, a draw length of 8” is the result of pulling the string (at the nocking point) back two inches.

I realize that this is not a big deal, its just one of those little things that I keep thinking about. 

[Pat B]

Yes, the draw length is measured to the back of the bow. To get an accurate reading of your force/draw curve you should measure as it is for your draw.

[radius]

so  if i read you, Pat, you mean that if the thing is braced at 7 and you draw it 1, you mark it on the f/d graph as 8...that's what i would have thought

[Barrage]

Really, it shouldn't matter as it's the area under the curve that is important.  You could brace the bow and call that 0".  That would give you a powerstroke length, rather than a draw length, so really it just depends on how you want to view your data.

[radius]

travis is right, but it's easier for us to communicate with each other if we standardize our terms.  I know i know i don't mean to sound like a nazi but it's true.

[The Gopher]

yup, you guys are right, i've managed to overthink things again.

[Barrage]

travis is right, but it's easier for us to communicate with each other if we standardize our terms.  I know i know i don't mean to sound like a nazi but it's true.

Radius, what, you, standarizing, cmon  lol.  You're right, of course, it is easier, but I still don't.    For instance, Pat mentioned above about measuring draw length from the back of the bow.  I never do - I always measure from the belly side of the handle because my draw length always starts there and at the end of the day, that's what I'm really concerned with.