Question for Bowyers on lam layup design?????

[warden415]

I want to try and use some veneers in a bow. I have in the past used a parallel in the core and two equal tapers on each side for a total of 3 lams. What I am thinking or wondering is.... if I use the same overall thickness, what change in bow performance or shooting characteristics would there be if I used the two tapers in the core and two thin parallel veneers on the outside for a total of 4 lams? Thanks Steve

[Apex Predator]

If your total lam taper rate is the same, the difference should by close to nil.

[twotimer]

i assume you are planing on taking the parallel lam you have been useing and making two out of it,ie,instead of say a .100 parallel,you will use two .050 parallel's,if your overall thickness is the same in the middle and at the tips,there should be be no difference in performance,or draw weight.regards,robert      

[warden415]

Twotimer that's exactly right. I was basically going to split the original parallel into 2 pieces.
I usually use about .070 core parralel and two  tapers that start about .070 on the fat endon each limb. The veneers i see are much thinner than .070
Maybe .030 or so. I figured they were too thin to start with to try and start grinding them into tapers. Just wanted to make sure it didnt matter if your core was made up of parralels or tapers.

[Peckerwood]

One small thing I have noticed in your scenario. If you add multiple glue lines it can add some weight to your set up( # at a given draw weight ). The shooting characteristics should be the same .

Bill

[kennym]

I've done it both ways,and can't tell any difference. As long as you keep the stack thickness and the rate of taper the same,I don't think you'll be able to tell the difference.

Bill has an interesting observation on the glue lines,wonder how that affects performance?

[mater]

Ive found that to be true also,that the glue lines add some weight. I think its because they add some thickness. Like you cant squeeze all that glue out.
         mater