Common mistakes in deflex/reflex bows?

[Aussie Yeoman]

Hi all,

I'd like to get into deflex reflex bows, having made longbows and flatbows (straight and perry-reflexed) pretty much exclusively for almost three decades, with one or two recurves in the mix. I've been teaching bowmaking classes for about 15 years.

So I'm not new to bow making by any means, but only to this particular style. I've tried once or twice, but it didn't end well. I think the problem was in having the belly slat too thick, and/or trying to go for too much reflex, in the glue up.

I'd like to hear from the experienced, what common mistakes beginners can make when constructing and tillering this kind of bow. Maybe even some of the uncommon but important to know mistakes too.

Cheers!

[Badger]

     R?D is still my favorite, but not as extreme as shown in the diagram. I have built quite a few like those pictured, and I have had a very high failure rate. My biggest mistake is getting a hinge in the middle of the limb where it just suddenly appears. I believe my biggest mistake on those is trying to go for too much reflex. If the tips are level with the back, they are not too bad to tiller out, but they are a nightmare with a few inches of reflex. My favorite R?D design is more like an R&D with a semi-recurve. I use a very similar form to the one Gary Anderson used. Hard to beat.

[Aussie Yeoman]

Thanks Badger, always good to hear from you.

Had you meant to attach a picture or link to one?

[Badger]

I was referring to the photos of bows in the other thread about bow shapes. I find that if the limb is straight at brace, I am in pretty good shape, but if it is still showing the dip from the deflex, it is under extremely high tension on the string and will twist itself into a knot.

[Aussie Yeoman]

Ah! I see. You mean #6 here? http://www.primitivearcher.com/smf/index.php/topic,73421.0.html

Or perhaps Post #13 in the same thread?

The D/R bows I've seen that are done well do seem to look pretty much dead straight when braced. I did some analysis of a couple and at full draw the bent limb looks to have the same degree and shape of bend as a straight bow with a ~7 inch brace. Doing that bit of graphics was pretty informative, because an elliptical bow at brace has very little bend at the inner limb. Which is something I probably didn't do well the time I tried.

[willie]

My favorite R?D design is more like an R&D with a semi-recurve. I use a very similar form to the one Gary Anderson used. Hard to beat.

Steve, I could not find a Gary Anderson, but can you share specs and a pic the side profile you like?
I can put it into virtualbow and tweak as you see fit.
the pics below for example, maybe too mild? maybe does not have the "semi-recurve" you mention?