Recurves vs. Reflex??

[mmattockx]

Did the string lay on the bow at brace? I'm just wondering where the increased string tension came from.

No, the string never touches the recurve, it is very much a flipped tip type of recurve. The extra tension comes from bending the limbs farther to reach brace. Compared to the flat bow version the recurve showed a maximum stress at brace 19.5% higher.


Mark

[bradsmith2010]

ok what does all that mean,, 

[Selfbowman]

I have only built a couple recurves and found no advantage in cast or speed.recurves require more mass in the outer limbs and  rob cast. Also for me 2-2-1/2” reflex is about all I have managed to keep-in the limbs with out excess set. That makes a 67”-69” pyramid the winner in the broadhead class. Not so in flight arrows. At least I have not found the right flight arrow for that bow yet. Reflex in the inner limb seems to cause more shock than on the outer . Don’t know this is the best design but it’s breaking records currently.  Arvin

[HH~]

Super tiller aint very primitive is it.

Close werks for me every time.

Hedge~

[mmattockx]

ok what does all that mean,, 

Probably much of what you already know through experience. Taking a flat bow and recurving the tips or reflexing the limbs adds energy storage at the expense of higher stresses in the wood. Stresses go up faster than energy storage, so it is a game of diminishing returns as long as your wood is up to the higher stresses or else you get a bunch of set or a broken bow.

And, as you pointed out, there is more to how a bow shoots than just energy storage. It still has to be able to get that extra energy into the arrow for any useful gains and those may come at the expense of user friendliness, longevity or other desirable characteristics.

Super tiller aint very primitive is it.

It's just another tool in making a bow, depends on if you think a primitive bow needs to be made using primitive tools/methods or not. I like to use everything I have available to me to learn and improve my results.


Mark

[Selfbowman]

Hedge if I understood the math I would use Super Tiller. Since I am math challenged I go with what makes since and performs after the build. More work and guessing but sometimes I get lucky. Arvin

[Selfbowman]

Also that caul at pappys must work it’s been there forever. Don’t know if it was designed with Super Tiller. I doubt it though. Arvin

[DC]

Hedge if I understood the math I would use Super Tiller. Since I am math challenged I go with what makes since and performs after the build. More work and guessing but sometimes I get lucky. Arvin

[HH~]

Got a few of em. I see ya when ya get here Arvin. Pyramids are where it at for sure but wood has to real clean to make em thin enough to keep limb mass down.
For all round shootin its hard to beat the American flat selfbow with a shelf.

Hedge~

[Tommy D]

So one of the take home messages from reading this for me is that the R/D profile is a very good option for getting the best out of a wooden bow. Now because technically the definition of a “longbow” is that the string doesn’t touch the tips once it leaves the nocks and an “English Longbow” is defined by its cross section - can one make a R/D ELB and have it still considered an ELB?!

[HH~]

Not by IFAA rules I believe.

R & D selfbows that are not backed and lamed up are not easy to make unless you have a piece of wood that kinds has those characeristics. Can be accomplished but to hold that profile like you see with a lam bow its just not that simple.

HH~

[PatM]

I wouldn't say that's true.  A heat treated  limb holds reflex in a regular bow so it's just a matter of deflexing the handle or fades with steam and reflexing the limb.  No lamination needed.

[Marc St Louis]

RD Elm self-bow

[HH~]

Asymetrical?

Just barely behind handle. They can be done as I said. I have made full partial working recurves outta elm not easy. Prefer it to a minimal R & D unbacked selfie any day.

This is early on with a winged elm full recurve where the curves actually flexed out about 1/2". Got gifted away to a fella down by Hendersonville, TN. This one was out if a very very nice section of old winged elm. A true dart slinger.



HH~

[Selfbowman]

Marc that’s a good design. I know they don’t take set or string follow. Now I know where Lonnie got his design. His is not as radical in reflex.  Arvin