Heat treating

[H Rhodes]

  I am reaching the finishing stages of an elm flat bow.  Bow is 2 1/4" at the fades and remains about two inches wide and then tapers to 3/8" nocks in the last foot or so....  I have already shot it in.  48# @ 28".  The bow is 62" NTN, with a barely bending handle.  The performance is really average.  yawn....   The bow showed about two inches of string follow and I believe that is due to wood being a little green.  I steamed some reflex into the handle and the bow shows zero string follow now, but I have set it aside and decided not to pull on it for a couple of weeks.  I am impressed with this winged elm.  It is one of those staves that you just know isn't going to blow.   
     I have read that heat treating the belly can improve cast.  How much improvement can I expect?  I have never applied dry heat to a bow, so this will be new ground.  I would appreciate any insights, predictions and advice. 

[PEARL DRUMS]

It varies greatly from bow to bow and wood to wood. Just try it and see what you think. There are a TON of tempering threads to poke through if you chose.

[Qwill]

I'm still experimenting with heat treating, and I still haven't really tempered the way Marc St. Louis describes in TBB4. I tend to use a quicker method, and I've had mixed results. I haven't had good luck with elm the way I heat treat, and elm is listed as superior in St. Louis' article. I'm excited by black locust, vine maple, douglas maple, yew, and serviceberry though. According to St. Louis, Black Locust can be prone to tension failures when heat treated, but I haven't experienced that.

Tentative Conclusion: Some woods will perform great with only a little heat, possibly because the woods are more balanced between tension and compression or something.  I've gained as much as 10 pounds of draw weight by heat treating. I just did a douglas maple bow that gained about 5-ish, and went from doggy to pleasantly average. Other woods like Elm may need more heat for longer to change the wood structure enough to make a difference. Like I said, I think there are differences between wood species in the type and duration of heat treating, but I need to experiment some more, as this is still only a intuitive leap based on my limited experience.

I do know, at least in my experience, heat treating, even the quick way I do it, will remove string follow, so it's worth the effort.

[Diligence]

http://www.primitivearcher.com/smf/index.php/topic,23338.0.html

I found this helpful....last elm bow I cooked (using Marc's method), really picked up some strength and zip with the heat treatment.

D

[H Rhodes]

Thanks PD, Q and D!  I am going to make sure this one is good and dry and then give it a shot.  I will let you know how it turns out.

[H Rhodes]

Okay, I tried  heat treating and am convinced that it will transform a bow!  This mediocre elm bow which was pulling mid forties at 28", with over 2 inches of string follow was toasted over the kitchen stove.  I propped it up and put the burner on high and toasted a section at a time, until the whole belly was brown.  The process took about an hour and a half.  I let it sit for a few days and noticed that it was a whole new bow.  It was noticeably stronger when I checked the floor tiller.  I attempted to string the bow but found it too heavy!  I had to retiller the bow down to 50lbs.  I have since shot the bow in for the second time.  50lbs. at 28" with zero string follow.  The tips were thinned down and now the bow is a really great performer.  I will post some pics later.  Heat treating elm worked great for me.

[Marc St Louis]

Glad to hear of your success Howard

[crooketarrow]

   I just finished a red elm 50#'s at 29 1/2. Longest draw leanth I've ever built.
 I've tempered many white wood bows. IT HELPS WITH SET AND STRING FOLLOW. Improves cast like someone said it all depends on the bow. WOOD IS WOOD
   Theres only one way of telling build the bow shoot it. Then temper see if it in proves the cast. To late for the set and string follow but you'll can tell if it inproves cast.
  I temper before I tiller.

[H Rhodes]

Thanks Marc.  I was a little skeptical after reading TBB 4's chapter on heat treating, but now I am convinced and will be adding it to my bag of tricks on future bows.  Thank you for your wealth of knowledge and sharing that with us new guys!

Crooketarrow, I had never applied dry heat to a bow before this.  I think you are right, and will be correcting set and string follow with my tempering processes earlier on, on my next bow.  And,  help us all, there will always be a next one.  No way to stop.  I wonder if there is a twelve step program for this....

[smoke]

Just last night I was looking over a hickory bow I made over the winter, amazed by how well it shoots - due in large part to Marc's method of toasting.  (Thanks again for enlighting us Marc!)

I also use the stovetop to toast my bows.  The only caution I have there is if you do elm on the stove, the smell in the house didn't much impress my wife.  Hickory on the other hand . . .

[Gus]

Yes Sir!

I agree Wholeheartedly.
After reading TBB IV, I've been using Mr. St. Louis's Heat Treating Method on Osage.
Six bows so far, and each one has gained eight to ten pounds and one or two inches of reflex.
Have several White Wood bows in the pipeline now and will be Tempering them as well!

Thank You Sir!

-gus