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Main Boards => The Bowyer's Bench => Topic started by: monterey on May 16, 2011, 05:12:00 PM

Title: A pyramid design question
Post by: monterey on May 16, 2011, 05:12:00 PM
First off, I'm a big fan of pyramid style bows but have never built one just for myself nor any in an adult size.

Here's my thoughts so far on design.  Fourteen inch riser, two inches wide at the fades straight taper from a point once inch beyond the fades to a 3/8" string nock width.  Glass front and back and maple core lams.  Somewhere in the 62" to 66" NTN range.

Here's my question;  would it be advisable to taper the stack out toward the tips as in a typical LB lay up or would it be better to keep the the limb thickness the same all the way out.?  Have also thought about some reverse taper in the limb tips but don't know what to think about that aspect.

Any suggestions??
Title: Re: A pyramid design question
Post by: razorback on May 16, 2011, 05:47:00 PM
I'm a wood bow guy and have never done a glass bow but would think th eprinciple would be the same. The tiller comes from the side taper so would think that thickness would stay the same.
Title: Re: A pyramid design question
Post by: hova on May 16, 2011, 10:46:00 PM
im not familiar with glass either , but i doubt a pyramid glass bow would be 2" wide. if it was , id guess on about paper thin at the tips...


sounds awesome. you forgot some pics...
Title: Re: A pyramid design question
Post by: don s on May 17, 2011, 02:03:00 AM
if it's a pyramid design the limbs should be equal in thickness for their entire length. imo. after all isn't that the purpose of the pyramid design? don
Title: Re: A pyramid design question
Post by: monterey on May 17, 2011, 11:00:00 AM
I'm in concurrence with all of you on the idea of equal thickness.  That's how I've built the kid bow styles and it is a functional design.  Ok, that feature is settled.  Now, how about this width question.  Am I going too wide at two inches?  I realize two inches is not necessary to the design but thought it might look cool.

No pics yet of course.  Still rattling around in my brain.
Title: Re: A pyramid design question
Post by: fish n chicks on May 17, 2011, 11:32:00 AM
Definitely equal thickness bud. They don't work like glass at all, and if you try to taper the limb thickness, you're going to end up creating moments (a point on a line being stressed with a load that is where the greatest amount of rotational force is) or hinges for ease of explaining, either at the riser, or at your tips.

Granted, with this art, you can try anything, but it seems like a murphy's law thing. Good luck! Pyramids are awesome!
Title: Re: A pyramid design question
Post by: hova on May 17, 2011, 01:44:00 PM
i wasnt talking thin thin , i should have said narrow. my apologies.


-hov
Title: Re: A pyramid design question
Post by: Dick in Seattle on May 17, 2011, 02:42:00 PM
Thanks for posting this thread, Moneterey.   I have had a couple of pieced of 2" brown .040 glass set aside for a pyramid project for three years now.   I'll follow your adventure closely.
Title: Re: A pyramid design question
Post by: monterey on May 17, 2011, 03:44:00 PM
I'll keep this build updated here, but don't hold your breath cause I got three more that have to come of my 68" form before I can go off on another crazy tangent.

The form should be very simple.  Not sure if I'll go rubber band or hose.  Probably hose, but OTOH it's nice to be flexible with riser shape and length too.
Title: Re: A pyramid design question
Post by: hova on May 17, 2011, 06:49:00 PM
dick sounds like its time to get on down to brown town.


goodness that sounds dirty...just get to it like only you can. pyramid with your  signature setback handle would be very interesting....


-hov