Asymmetric riser/handle longbow

[SJTalley2004]

I started tinkering with building bows sometime late 2020 or early 2021. First design was one of Kenny's 58/60" forward handle bows. Awesome design, but not knowing what I was wanting I built a dozen or so, gave a few to friends, kept a couple and cut the rest up. Built a mild r/d that I never could get 2 to tune the same, not to mention I always felt rushed once I started building, and grew to dread my time in the shop. Took a break from building, cleaned and changed my shop layout a little, built a slight backset ASL, got one shooter out of 3 that I still have, then moved on to 3 or 4 different revisions of a 3 piece until I hit burnout from frustration last winter. Started tinkering with a very mild r/d form that would end up sitting on my bench for months now. I've been pondering coming up with something that doesn't really draw from any other bow I've seen recently, that being an r/d with an asymmetric riser and a more recurve shaped grip. Working from home now, I think I can finally start tinkering with putting this idea on paper, but I'm wondering if anyone using any sort of CAD program to help work out the kinks and dial in optimum performance through automated testing before the first bit of sawdust flies?

[derekdiruz]

While I do not use a CAD program for performance generating, I use my CNC for 90% of my bow building these days.
Limb profiling, shelf, grip; tips are about the only part I don't do with the CNC.

[mmattockx]

Since no one else replied about software, I will.

There are a number of analysis programs you can use to help with bow design, but mostly they are not super user friendly and it's very helpful to have some engineering background to understand inputs and outputs.

1) Super Tiller - Created by Alan Case, very versatile and flexible overall. It allows all sorts of bow side profiles such as flat, reflex/deflex, recurve, etc.

2) Woodbear's Spreadsheet - This is an Excel spread sheet developed by David Dewey, who goes by the handle 'woodbear' on a number of archery forums. It only works with flat bows, you cannot model anything else with it and it is really intended only for use with all wood bows. You can model fibreglass lam bows if you know how to fake out the material properties, but that requires engineering level understanding of mechanics of materials and beam bending.

3) Virtual Bow - This is the most current software, with ongoing updates and support (I think). I've never used it, but others here have and can give you a better review than I can.


Mark