Belly tempering ?

kodiakkid · July 20, 2009, 08:30:00 PM

What is the proper way to temper the belly of a bow? I have heard this could possibly add pounds to a bow. Is that correct? I have an osage selfbow that turned out a bit light. I would love to add about 5-7 lbs to it if possible. Thx, Paul<><

2treks · July 20, 2009, 09:58:00 PM

According to what I have done it will add some weight to a "White wood" bow not 5-7 pounds tho. According to what I have read, it will not have the same effects on osage. I have not Tempered an osage bow, tho I have heated and straitened an osage bow maybe 5 or 6 times(the same bow) and it has worked great. I am not sure if it was "tempering" it at the same time.
As far as how to do it, I clamp my bow to a skinny form(1" wide)and take a heat gun and hold it on the belly side about 2-4" off and let the wood get real Brown. Do not make it like charcoal but get it DARK! You will need to adjust tiller after you let it(bow) stabilize for a few days on the form.

Diamondback59 · July 20, 2009, 10:09:00 PM

i only heat till to hot to touch with other hand NOT brown and i dont think i ever noticed a diff on osage on other woods white woods yep but not osage brock

Pat B · July 20, 2009, 11:46:00 PM

I have tempered my last two osage bows and I think it definitely makes a difference. I like to get the belly wood(not the sides or back) to a nice chocolate brown color. I wasn't looking to add weight but to lessen string follow so I don't know how much you can increase the draw weight by tempering. By flipping the tips(slight recurve) a little you can gain a bit of weight too just remember the give and take of wood bow building.

Hermann From Bavaria · July 21, 2009, 03:20:00 AM

i might try it! i tempered several bows now, and it made a difference. at about 150 degrees celsius (dont know whats in fahrenheit, cause i´m german) the lignin in the wood cells starts a reaction and makes the wood more pressure resistant. so you will get more draw weight, and more power on arrow.

kodiakkid · July 21, 2009, 05:48:00 AM

Thanks guys!

vanislebowyer · July 21, 2009, 10:10:00 PM

After tempering, do you scrape down past the dark wood? Do the effects of tempering go deeper than the wood which is actually seared?

Pat B · July 21, 2009, 10:31:00 PM

The charred wood is just the indicator that the wood is cooked. The heat treating goes in as far as the heat does.
Once you heat treat the belly, allow a few days so the wood can rehydrate back to a safe level before you stress the bow.

vanislebowyer · July 21, 2009, 11:18:00 PM

great Pat...resists string follow, eh? hm, a little string follow is a good thing, i've heard...some quote like, "the sweet sendoff like a longbow with an inch of string follow,"....from one of the TBB's...

shamus · July 22, 2009, 06:52:00 AM

It's covered in great detail on the Traditional Bowyer's Bible, Vol. 4. You might want to give it a read.

Springbuck · July 22, 2009, 11:27:00 PM

I heat it until the color changes, but I DO NOT char it. You have to heat it slowly and deeply to make the change.

I could easily see it adding 5-7 lbs on a bow, but probably not a light one, 7 lbs on a 35# bow would be a high percentage of the weight, but adding 7 lbs to a 60 lb bow, nice and wide, might happen.

If done properly toasting WILL add some weight and will prevent or reverse a certain amount of set. I have taken bows with 2" of set, toasted them over a form into 2" reflex, and shot the bow in, keeping 3/4" to 1" reflex. You have to do it right, but it definitely improves performance.