Author Topic: New bow, hybrid between molgabet and recurve  (Read 3910 times)

0 Members and 1 Guest are viewing this topic.

Offline bubby

  • Member
  • Posts: 11,054
Re: New bow, hybrid between molgabet and recurve
« Reply #15 on: February 10, 2017, 03:13:28 pm »
Unfortunatel you have picked two designs that are not compatible to be combined. A recurve needs outer limb width to ensure stability and a narrowed outer limb bow is made that way to minimise outer limb weight and is therefore very narrow which would equal little stability for the lateral forces a recurve can exert during the draw.
Make one or the other is my advice. They are both great designs in their own right. Combining them would mean you wouldn't get the benefits of either. You can of course reflex the outer limbs of a narrowed outer limb bow but there is a limit. The more you push the reflex the heavier they need to be.

I don't know mike with a little tweek here and there they will work
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline bubby

  • Member
  • Posts: 11,054
Re: New bow, hybrid between molgabet and recurve
« Reply #16 on: February 10, 2017, 04:28:05 pm »
If you make the limb 60% and the lever 40% or there abouts you are ok, i personally don't think a molly is a good beginners bow to build though, a pyramid i think is the best to start on or a standard flatbow are better options
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline PatM

  • Member
  • Posts: 6,737
Re: New bow, hybrid between molgabet and recurve
« Reply #17 on: February 10, 2017, 05:02:30 pm »
Unfortunatel you have picked two designs that are not compatible to be combined. A recurve needs outer limb width to ensure stability and a narrowed outer limb bow is made that way to minimise outer limb weight and is therefore very narrow which would equal little stability for the lateral forces a recurve can exert during the draw.
Make one or the other is my advice. They are both great designs in their own right. Combining them would mean you wouldn't get the benefits of either. You can of course reflex the outer limbs of a narrowed outer limb bow but there is a limit. The more you push the reflex the heavier they need to be.

Though I have made two bows that might be kind of considered to be Molly/Recurve Hybrids, Mike is Right here!  I wound up having to add hard wood laminations on either side of the curved Molly ends to regain the lateral stability I lost when narrowing the levers initially.  It looked a little funky and though the hand shock the extra weight created was very minimal, The performance was sluggish compared regular Molly's or a recurve. 

I still plan to make another run at this design, but I'm still not sure how to make it work optimally.  I'm thinking to try really light weight wood for the siyah material and then use a thin flattened piece of cow horn as a single layer lamination sandwiched between two sides of ERC or yew.  IDK - maybe that'll be stiff enough without being too heavy.

OneBow

BTW - If this is a first of early bow for you, please choose to start with a design that would be more likely to produce an effective shooter.  I think you'll be happier with the results.


 That's exactly why the Asiatic bows went to the side plates of bone but that means the design is just fine. It just needs material adjustment. They didn't make those bows just to make things difficult.

Offline Shadowcleaver

  • Member
  • Posts: 11
Re: New bow, hybrid between molgabet and recurve
« Reply #18 on: February 13, 2017, 04:27:05 am »
Thx a lot for all the tips guys. I'll follow your advice and make an easier design first and then try my hand at the hybrid with the 60 % limb, 40 % static. I have some nice ash and hickory boards coming in so i'll keep you updated :-)

Offline Springbuck

  • Member
  • Posts: 1,545
Re: New bow, hybrid between molgabet and recurve
« Reply #19 on: February 15, 2017, 02:39:15 pm »
I don't buy the width equals stability theory. A Mollie is just the first step towards a static recurve.  As you increase the angle you need to extend the working limb length and decrease the static portion perhaps but not the outer limb width.

Ha!  This is it, right here.

I have succeeded with a slight reflex on the static portion of a molly at the transition point, but keep it sane.  The more reflex or recurve, the shorter that section needs to be.

The bow Bubby linked is the right approach.  See the slight deflex in the inner limbs, and the very conservative flip toward the tips, with plenty thickness?
« Last Edit: February 15, 2017, 02:43:05 pm by Springbuck »