So ya all want a BBO build?

[oldandslow]

And I thought 140 was hot!

[Longcruise]

Bingham makes it sound risky to be without adequate heat..........which, of course, can't be achieved without their thermostat. 

[kennym]

Sorry yer knot got ya Roy. 

I still heat all I build except the TD I've used hunting and target shooting for last 4 years .

I cured it at 70 in shop , but feel better about heat resistance when I heat .  But it does cure at 70 I reckon...

[Flem]

Is it possible to leave a little extra meat around the pin knot like you would with a self bow?

[Roy from Pa]

These belly lams were quarter sawn and the pin knot ran the whole way across.

Should have cut it up when I seen the knot.

Thanks Kenny

[kennym]

On a positive note, it's still winter Rody ...

[Roy from Pa]

Rody?
LOL

I just seen the Kednny

LMAO

[oldandslow]

what is trapping?

[Mad Max]

what is trapping?

Start at the fade and sand to the tip on 1 limb to make it weaker

[mmattockx]

what is trapping?

Usually the chamfers are much bigger than shown in MM's drawing. It is called trapping because you make the limb cross section into a trapezoid (or close to it). The attached picture shows two ways to trap a bow limb. The wider side of the section is the belly side.

Fibreglass bowyers and wood bowyers tend to use it for different reasons. As MM says, it reduces limb stiffness. FG bowyers use it to drop weight when a bow turns out much heavier than intended. Wood bowyers use it to reduce stresses on the belly and increase them on the back. This is done because wood typically fails in compression well before it fails in tension. Trapping helps to balance the stresses so that the belly doesn't fail well before the back.


Mark

[Roy from Pa]

Trapping for a BBO bow is about the same as the facets I rasp in the back and belly edges of the limbs. But you take the facets on the back of the bow in further to trap it more like Mark stated above.

[attachment=1,msg2946658]

[attachment=2,msg2946658]

[oldandslow]

Thanks guys...that actually helps me understand why I may have broke a couple

[oldandslow]

Roy it's hard to judge in a picture, are you coming in about a 1/4 inch on the belly in those shots?

[Roy from Pa]

Yes, but as I move towards the tip area I narrow them more because the tips are 1/2" wide..

Prolly only 1/8th at the tips.

[Mad Max]

Trying to picture the tiller process on a  glass bow...

He asked this ? on comment #262
That's why I said one limb my bad

[oldandslow]

Trapping for a BBO bow is about the same as the facets I rasp in the back and belly edges of the limbs. But you take the facets on the back of the bow in further to trap it more like Mark stated above.

[attachment=1,msg2946658]

[attachment=2,msg2946658]

Bear with me now...I am a little slow.
So your saying that the back gets more chamfer than the belly?

[Roy from Pa]

Bear with me now...I am a little slow.
So your saying that the back gets more chamfer than the belly?

Only if you want to trap the back more.

I normally do the back and belly the same.

But trapping the back on a wooden bow is a good thing.

So yes you could put more chamfer on the back.

[oldandslow]

K. Good info. Thanks again!

[oldandslow]

Afraid to go past 23 inches...lol

[oldandslow]

I can see my left limb needs some work.
Anything else?