Designing for very heavy wood (preferably without needle tips)

[Wingit]

I've just cut some really really dense stuff, mountain mahogany, about .95sg. Rather narrow and light outer limbs are in order for such a dense wood, but I really struggle with needle tips; I prefer to keep them around 3/8in for stability, and because I prefer pin nocks.

I initially considered a pyramid design tillered using the mass principle, but the stave is pretty narrow (about 2in after squaring the sides) and I'm a bit worried about the crown. So that got me thinking: maybe a standard flatbow with Sudbury-style fades? Like a 10-12in stiff section handle for a 68in bow, so it has the stack of a long bow and limb mass/movement of a short bow. Thoughts? I'm very open to other design ideas too, these are just my initial impressions.

[superdav95]

I’ve never done one with mahogany.  I imagine it can be done as with a power lam with riser from mahogany backed with something.  If it’s dense and hard but not particularly good resistance on compression then one may have to belly lam with something that is.  I think a cool bow combo might boo backed with Osage belly lam with that dark core would look smashing. 

[Wingit]

It's not a true mahogany, and nothing at all like it. I think it's in the rose family. Properties are similar to Osage, but stronger in tension and stronger in compression proportional to its greater density. Also you can use the sapwood. I'm only interested in a self bow, as a lam would be unnecessary. I'm looking for advice as to how to manage hand shock/efficiency with such a dense wood: I was considering a flatbow with long Sudbury style fades to reduce working limb mass without requiring needle tips. Wanted a second opinion

[RyanY]

If your tiller is good without too much inner limb bend, you shouldn’t have to worry about hand shock with 3/8” tips unless you keep too much width in the limbs.

[Jim Davis]

I stick to pyramid design. I might use ELB for yew, but pyramid is my standard.

I can't see 3/8 tips being a problem. Your 2" width is probably more than you need.

I have never used mountain mahogany and I can't find mechanical properties for it. I did find it described as brittle, but sometimes used for bows by the indigenous Americans. Also found a claim that its SG was a touch more than 1.

[superdav95]

It's not a true mahogany, and nothing at all like it. I think it's in the rose family. Properties are similar to Osage, but stronger in tension and stronger in compression proportional to its greater density. Also you can use the sapwood. I'm only interested in a self bow, as a lam would be unnecessary. I'm looking for advice as to how to manage hand shock/efficiency with such a dense wood: I was considering a flatbow with long Sudbury style fades to reduce working limb mass without requiring needle tips. Wanted a second opinion

Ah ok Roger that!  Yes then advise given by Ryan and Jim is what I would do with it then.  Sounds like a cool project and interesting wood to use.  Keep us posted on your progress. 

[Selfbowman]

If you want to have no shock I would go as narrow as possible at tips.adds speed also. 3/8 will work it will just have thinner limbs out as n the ends.

[Badger]

 Hard to beat a pyramid design, especially when you don't know the wood that well. I think Mountain mahogany might be slightly prone to chrysaling so you might want to give yourself as much working limb as possible. It will also help you avoid set.