Any tips for Mollegabet bows?

[Julian]

I'm working on a molly board bow at the moment. I've started shooting it in, seems pretty good. about 30# @ 28. I'm going to post pictures in a bit; waiting on the glue to dry for my tip overlays

tiller isn't fully worked in.

Does anyone have general advice for this style of bow?

[Del the cat]

With it's short working limb, make sure that whole section is working and that you haven't just got a grip, two hinges and two levers!
Also feel the stiffness of the levers and reduce the width bit at a time. We often see them with what looks like girders on the end.
(Exaggeration is for comic effect. Other comic effect are also available, especially as it's Halloween... now where di I put the old "arrow through the head" gag?)
Del

[Julian]

Here's my progress:



I piked the bow to remove my temporary nocks, then I shaped my overlays and thinned the levers. I went over a few problem areas with the tiller but I'd love some second opinions.

currently: ~62" ntn. feels like 30# at about 24# now. Would love to get bang on 35# at my 27" draw.

Edit:

I'd have no qualms getting this bow to bend a little bit through the handle, if that would help the performance. I'm planning a layered leather grip, if I can get my hands on some nice stiff leather.

[Julian]

Here's the levers:


That's my thumb, for scale, and I don't have a particularly fat one. Seems pretty thin to me! Would love if someone would post a pic of the final thickness / width levers on their bow for comparison's sake. I know I could go thinner, because they're certainly not bending.

[Del the cat]

Just measured a couple of my Molle' flight bows (around the 50-60# poundage).
One is 14mm wide x 18mm deep (mid way along)
Other is 13mm x 19mm
They are both a sort of blended T section or V  rather than a rectangle so they are a lot narrower on the belly side and the side faces are concave.
https://bowyersdiary.blogspot.co.uk/2015/07/whew.html
https://bowyersdiary.blogspot.co.uk/2015/07/molle-distance-shots.html
Del

[bushboy]

Brace looks good.need a front profile to comment on lever width.

[Julian]

Brace looks good.need a front profile to comment on lever width.

Not a great photo, but hopefully u get the idea.



Pyramid style limbs, with 2" fades into the levers. So I guess you could call it a pyramid mollegabet hybrid. idk if that's even a good idea, design wise, but that's the limb profile that I'm comfortable tillering for the time being.

[Del the cat]

The working limbs will still need a little thickness taper because the width doesn't taper to zero.
Del

[joachimM]

at 30# draw weight only, you can surely narrow the tips of the limbs a lot more, which will improve cast and reduce hand shock. You don't need a lot more than 6 mm wide, but go for 7-8 mm and it will still be more than strong enough. It seems like it's currently close to 13 mm wide, just over 1/2"?

At the very tip, you can also make the tips thinner, as that wood is hardly strained. You'd be amazed at how thin and narrow you can get away with.
 

[Julian]

hmm, ok, will do. Marked out a taper from 8mm to 6mm along the levers. I'll update when I get the rasp out tomorrow

[Stick Bender]

The bow in the pic is a parallel limb design but the limbs due constant taper in width from mid out but some of the concepts are the same , you can Effiletower the leavers if you want to save mass & your bow is very low draw weight so I think you could get them a lot lighter in mass but be warned if you get them bending you will lose FPS I learned that threw trial & error I will give you the measurements on mine only as a example because draw weight and wood make a difference in the dimensions Width is 0.69 to 0.54 at the tips before the pin knock flare and thickness is 0.61 out of the fade to0.54 tips over 8 1/2 statics if you happen to get to light and start to bend you can usually heat treat back ridgid but try not to go there , I don't think there is a canned answer to your question on statics there is a ball park but to many variables bow to bow it's a matter of trial and error !

[Stick Bender]

Side

[Stick Bender]

Front

[Julian]

Update:





picture is a little cluttered but you get an idea of the profile

[Weylin]

With it's short working limb, make sure that whole section is working and that you haven't just got a grip, two hinges and two levers!

Hahaha! What Del said. Seems like a lot of the molle's I see fit this description (including my first one). You seem like you're doing pretty well on yours. Look forward to seeing how it turns out. It's not an easy design to pull off well.