Author Topic: heat treating  (Read 2747 times)

0 Members and 1 Guest are viewing this topic.

Offline mspink

  • Member
  • Posts: 213
heat treating
« on: November 14, 2010, 09:35:35 pm »
hey,, was just wondering how long to expect benefits from heat treating.. is it only a short term thing or long. I heat treated the limbs of two bows after finish tillering them to begun with. added about 3 inches of reflex in both. on e is a bend in the handle pyramid, the other a d style, both of maple. heated them both untill the belly wood was dark brown, not black.. excited to see the results,, they are both reaching equilibrium in the basement right now.. from the heat treating mavens out there,,, what can i expect??
Aim small miss small!

Offline Keenan

  • Member
  • Posts: 4,824
Re: heat treating
« Reply #1 on: November 14, 2010, 09:59:45 pm »
 If done right and the bow is built right and not overstressed it should last the life of the bow.  Wood type plays a role but most heat treating will hold well when done slow with deep heat. If just surface heat its effects are more minimal.

Offline Parnell

  • Member
  • Posts: 5,556
Re: heat treating
« Reply #2 on: November 15, 2010, 12:12:32 pm »
What type of wood?  Hickory pays the most, but I've also seen results with hackberry, elm and maple, oak.  The "white" woods.  I've found that, depending on the type of wood, treatment is best done first at ground tiller.  I've gone from browning the wood to turning the wood basically black, but not charred from a lit ember.  Much darker than I first started doing and it has better results.  With the extra wood still there because it's only at ground tiller it will be scraped off anyhow and you are really compressing the wood cells early on when the greatest benefit will be reaped.  I don't think the bow will be as heavily affected by the treatments once it's tillered.  Initially, and mid-tiller pay off the most, I think.
1’—>1’

Offline Josh

  • Member
  • Posts: 3,367
  • Silence is golden but duct tape is silver.
Re: heat treating
« Reply #3 on: November 15, 2010, 01:59:44 pm »
I started heat treating all my bows and I noticed a great improvement.  I usually get it floor tillered and give it it's first heat treating session and add a few inches of reflex at the same time i am also lining the tips up with the handle.  I do like Parnell and give it a good slow heat treating at this time holding the heat gun further away to get the heat into the middle of the bow.  I give it a week to re-hydrate, then I tiller it out to brace height with the long string.  Once I reach low brace, I re-heat treat it giving it a little more reflex and re-darkening the wood that was scraped off getting it to brace height.  I also tweak the string alignment during this final heat treating process if it needs it and give it another week to re-hydrate before final tiller.  Since I have been doing it this way my bows seem faster and hold a little more reflex than before and so far it has all stayed with the bow.  Hope this helps.   :)
“The trouble with quotes on the Internet is you never know if they are genuine.” —Abraham Lincoln

Offline Bevan R.

  • Member
  • Posts: 1,691
Re: heat treating
« Reply #4 on: November 15, 2010, 02:09:11 pm »
I would really be interested if someone would do a heat treatment build along. This is interesting but I would need more info before I try it. Are you guys only treating the 'white' woods and not Osage?
Bowmakers are a little bent, but knappers are just plain flaky.

Offline Josh

  • Member
  • Posts: 3,367
  • Silence is golden but duct tape is silver.
Re: heat treating
« Reply #5 on: November 15, 2010, 02:12:54 pm »
Marc St. Louis did a fantastic buildalong in The Bowyer's Bible Vol. 4 that is where I first learned about its benefits...  He literally "wrote the book" on how to do it.  ;D ;D
“The trouble with quotes on the Internet is you never know if they are genuine.” —Abraham Lincoln

Offline NTD

  • Member
  • Posts: 1,771
Re: heat treating
« Reply #6 on: November 15, 2010, 02:24:10 pm »
Heat treating or how 1500 watts saved my bow!  It's good stuff!                                  Gordon's build a long covers heat treating.
Nate Danforth

Offline JW_Halverson

  • Member
  • Posts: 11,881
Re: heat treating
« Reply #7 on: November 15, 2010, 02:56:01 pm »
Bevan, I just finished reading the chapter in TBB IV on heat treating and I'm still getting my head around most of the "whys and hows", but it seems that the denser the wood, the less it responds to heat treating.  Osage is about maxed out in compression strength, the heat treating can't add much to the bow.  (More fuel for those yeller wood fanatics to boast about  >:D)

I'm glad to hear hackberry responds well, I have one that came in lighter than I wanted and I think I will sacrifice it to the testing of heat treatment.
Guns have triggers. Bicycles have wheels. Trees and bows have wooden limbs.

Offline NTD

  • Member
  • Posts: 1,771
Re: heat treating
« Reply #8 on: November 15, 2010, 03:27:22 pm »
JW, while 'sage is dense its one of the woods Marc reccomends for treating.
Nate Danforth

Offline Pat B

  • Administrator
  • Member
  • Posts: 37,542
Re: heat treating
« Reply #9 on: November 15, 2010, 04:31:10 pm »
I've had good luck heat treating osage. If I am doing some straightening I'll do that first using oil and the heat gun but then when I unduce backset I will do this without oil and heat treat as I work out each limb.
  I do believe heat treating works best on compression weak whitewoods but so far I have been impressed with heat treating osage too.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC