Curves pulling out.

[Morgan]

Let me start off by saying I have not fooled with putting recurves in much at all. Several months ago I started a bow and curved the last 8” or so. Almost all of the “recurve” pulled out while tillering the bow on out. I put recurve in quotes because I’m going for more flipped tips rather than recurves. I want to pull the tips as far forward as I can without having string contact with the belly. I put the nearly finished bow up to fool with later. Pretty sure I know why they pulled out. Certain the tips are too thin.. I make all of my tips as lean as I can and keep them non bending. I am thinking about bending them again and gluing a thin belly lam at the tips to stiffen them. I will also be dropping the weight from 55 to 30-35 because my 11 year old is outgrowing his last bow. If I add a belly lam, how do I keep the tip mass down?

[Del the cat]

Sounds like you are going the right way to fix it... (thin belly lam on flipped area).
To minimise weight narrow the tips... but get 'em right first
IMO you don't get ow't for now't so reflex, flipped tips etc always have some sort of downside (usually reduced usable draw length)
Del

[PatM]

What is  the wood you are using?

[Eric Krewson]

I like to glue a long tip overlay one some statics, partly for looks and also to strengthen the curve.

[Santanasaur]

Those are some awesome overlays Eric, very cool!

Morgan are you steaming the bends? I’ve found that with many white woods the recurves hold better if you lock the bends with a heat gun after steaming. I don’t think this is necessary for all woods. Osage doesn’t seem to need the extra step.

[gutpile]

Eric beautiful overlays.. I only build statics simply for the reason working curves eventually pull out of self bows.. unless sinewed and they still pull out some.. gut

[mmattockx]

If I add a belly lam, how do I keep the tip mass down?

Narrow and thick is the most structurally efficient way to make static tips.

I only build statics simply for the reason working curves eventually pull out of self bows..

Do you use heat/steam to put the bends in or put them in with a lam glue up?


Mark

[DC]

For a selfbow steam and then dry heat is the best you can do that I know of. You've had suggestions for overlays and underlays. I'm leaning toward overlays. What I do know is that laminated recurves don't pull out so if you glued a thin strip of boo on the back they should be rock solid.
https://www.primitivearcher.com/smf/index.php/topic,68856.0.html

[Pat B]

A narrow, thick tip is stronger than a wide, thin tip and are physically lighter. 1/2" thick is plenty of thickness and near the end of the build you can reduce the wider tip to 3/8" or less at the string nock.
 When making recurves or any bow for that matter I leave the tips wide(3/4" or more) until first brace. Then I can see how the string tracks. I trace the outline of the string on the braced bow and narrow the tips accordingly.

[hoosierf]

You can also kerf the tips but sounds like they may be too thin. A few times I’ve kerfed them back 6-8”. Then glue them back with the curves you want.  You don’t necessarily need a filler lam but I used a coping saw to avoid taking too much wood else you need a lam to take up the space.

[DC]

Yes, I forgot about kerfing. Works great

[Morgan]

Thanks for the replies guys. I will try putting the curve back in and building up an overlay. To answer a few questions, the bow is hackberry and dry heat was used to put the curve in.

[PatM]

Use steam or boiling.  Hackberry  should bend more easily that way.  You can always overdo your bend a bit and then use dry heat to dial in your final curve. 

[Morgan]

Thank you. I will try boiling. Can you set with dry heat in the caul directly after boiling, or do you have to wait for the wood to stabilize after boiling?

[bushboy]

Better to leave them sit for a while before dry heat....they can fracture if moisture is left behind....turn them dark brown and they will stay put mostly....