Heat treating

[Loren Holland]

Been experimenting with some crate myrtle my Dad brought me. my first real attempt at a stave. removed the bark and cambium, left it at the first ring. was careful to leave the few small knots intact. let the dry at partially completed dimensions, so it wouldn't warp or check. within two weeks it was ready to start working down. I tillered it, and noticed a slight propeller twist, it tracked a bit left, but i didn't know it needed to be straightened. The string crossed the handle just left, so in effect it was like being center shot, so i left it.  The bow came in a little light, and i figured while i was experimenting, i would try to heat treat the limbs.  Holy Cow! i had no idea how much the limbs would stiffen up. the brace height reduced from a fist mele to about and inch, and the prop twist is now more pronounced...and i am at the end of my experimenting without some advice;)

[Bruce Prosser]

Hi Loren,

I have run into some of the same problems with Hickory and Osage, and walnut and, and, and,...

First, how long is your stave? Can some trimming be done to make a shorter bow? What is your draw length that you want to finish at? Can it be shorter?

Propeller twist is a drag, but I have made some really nice short draw bows with them. I have also made some nephews and neighborhood kids very happy with my hunting weight bows turned youth bows too.

I now try, when cutting my own timber for bows to keep the logs a little long. Just some info that I have learned over the last three years of my own attempts at making weapons of deer destruction!

I am not familiar with this wood as a bow wood, but when I cut a tree smaller than 8 inches I strip the bark immediately and spray spar urathane on what will be the back of the bow (unless it is osage, then I split and spray the ends and lay hands on it and pray and watch it close for the first week for excessive checking) and split it and then leave it sit for at least a month.

I have even cut some hickory saplings and immediately debarked, urathaned shaped and floor tillered them and laid them up in a reflex-deflex form to good results.

I would really like to see what this wood looks like.

Blessings, Bruce

[walkabout]

prop twist doesnt really matter that much just looks bad if you look on georges site hes got a post of a bow that literally looks like a propeller and it still came out fine. if it were me id still try to make a shooter out of it, just go slowly and try to keep the string nocks pulling evenly thats the major issue.

[shamus]

I tillered it, and noticed a slight propeller twist,    

If the limb has a propeller twist when unbraced, then the the propeller twist is natural. That's nothing to worry about.

But if the limb is propeller twisting as it is drawn, then that is because of an improper/uneven thickness taper, and THAT has to be addressed. In that case, the limb is twisting to the weak side. Remove wood from the other side of the limb.

[red hill]

Loren, I've not read anthing about using crete myrtle for a bow.  I have wondered about it though. I'll be interested to see your final results.
Good luck.
Stan

[walkabout]

what shamus said.lol. i just naturally just figured the twist was natural. if not though it can be fixed with patience, its even better if the bow still has a lot of tillering to go because twists can be tricky.heres a post i did awhile back when i was trying to make sense of prop twist and how to adress it.  http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=125;t=003160#000000  the example illustration isnt the best but sam explained which side would need scraped and ive done this since with great results. keep us posted if you continue work on this one.

[Loren Holland]

appreciate the responses...
red hill-TBB (forget which volume) listed it as similar to dogwood (haven't used that either), it is very white, thin ringed, and super flexible. I might not have let it dry enough, i will let the next one sit longer. i will say that it responded to heat treating like nobodies business
walkabout-you reinforced what i was thinging at first, that i didn't need to fix it in the first place as long as both tips move together. i think i will just retiller it a bit , make sure that it still lines up the same when i get it to brace height again, and shoot it
i think it was Forrest Trekker that had a method of straightening prop twist with vise grips and dry heat, i was thinking of trying that, but now i will just adjust the tiller and then post a picture, if it shoots, it shoots, right?

[walkabout]

prop twist is really just another type of character, so long as it isnt caused by the tiller and is in the wood to start. just as with snakey bows as long as the limbs are doing their part equally and the string stays in the nocks its just another challenge for the bowyer. possibly let the bow sit awhile and balance the moisture content before you start working on it again though, it sounds like there was alot of drying left to do and you essentially dried it quickly with the heat treating.i think someone said to weigh the bow and when it stops to lose or gain weight then its moisture content is balanced