Best time to steam recurved tips?

[adb]

I generally induce recurves when the stave is brought to first brace. I find it easier to reflex the tips when there is less material. Like Ryan O, I prefer steam or boiling, as I have also ruined several nice staves with dry heat. I just ruined a nice yew stave by trying to recurve the tips with dry heat. One tip turned out OK, but the other cracked on the belly side. It's difficult with dry heat to get the wood heated completely through, without scorching the outside. The internal temp of the wood must be high enough to provide enough plasticity to make the wood bend without breaking. Dry heat works very well for tempering belly wood.

[Dane]

Dane, if you shellac the area to be steamed you can eliminate most of the moisture that will get into the wood. The heat and moisture shouldn't affect the shellac and you can remove it later with light scraping or sanding or wipe it off with alcohol.

Pat, thanks, I recall that advice from elsewhere, and you reminded me of it.

I did some work on the stave after work today. Some honking big knots, but considering that the sapling bow held together, why not try with a knotty hickory stave? The wood works so well with a spokeshave and draw knife. Fun just reducing it. The other tool I really love right now is a small adz I have. Great little tool.

Dane 

[Pat B]

I can get wood plenty hot with dry heat without scorching. Hot enough that gravity brings the bow down just with the bow's own weight. The reason I use oil with dry heat is to help hold the heat longer and help distribute the heat evenly...without scorching. If the wood begins to cool before I'm ready I just reheat.
   Even though this method is quicker for me, I don't rush anything. When the wood is plastic enough to bend the wood will tell you.

[GregB]

I tried putting a pretty radical curve on an osage bow recently and used oil on it. It lifted splinters on the belly even though I really took it slow and thought it should be thoroughly heated before bending. Keep in mind it was a good sized curve! I've flipped the tips on other osage bows using this same method in the past without any problem, but not as radical a curve.

I think I'll either steam or boil in the future when putting on large curves...probably steam with osage and boil with white wood.

Pat, Gary Davis uses the shellac method when steaming that you mentioned. He mostly works with osage....wonder if it would help any for boiling white wood?

[Ryano]

Maybe your heat guns a diferant tempature or something Pat. I've tryed it time and time again with mine with cooking oil ,crisco, olive oil, bear grease, you name it.....I still get the same results. Maybe a lower heat setting at a longer time would help?  I've decided its just not much more work to steam them and the results are consistantly good for me so thats probally what I'm going to stick with. Good point about using some sort of finish on seasoned wood when you steam. I had a bow dry check on me once because I didnt do this. I now put a coat of poly on everything before I steam it.

[Pat B]

I read about the shellac from Dean Torges book, Hunting the Osage Bow.
  The cool thing about what we all do here is there is no right or wrong way to go. What works for some may not work for others and vice versa. These are all suggestions that have worked for each of us and it is up to the new guys to take all the info, do a bit of experimentation and decide what works best for them. Without the experimentation, we'd all still be making bows just like the original TBBs and earlier books told us to do. Instead, we took the bow building ball and ran with it...and look at the bows that show up on BOM each month. There are lots of our past mentors that have big smiles because of the way we took the baton and improved on their previous work.

[knap_123]

 it common after you steam to have checks appear?  i steamed some reflex on a bow at the handle and had checks appear in the middle. i added super glue and wraped them but what caused it?

[Pat B]

What causes the checks is adding moisture to a dry stave(swelling it) and when it dries the wood shrinks causing checks. By coating with shellac or other sealants that can handle the moisture and heat, you prevent the moisture from entering the wood in the first place.

[GregB]

Good stuff! 

[Dane]

This is good stuff. I'm glad I asked this question to start this discussion.

I just reread the chapter on recurving in TBB Vol. II. No mention (I think) was made of sealing tips before steaming / boiling. Cool to see techniques and methods evolving almost before our eyes.

Thanks everyone.

Dane

[Christophero]

Pat,
You've just got to show a pictorial on how you dry head and use the metal banding at the same time.  I just cannot get me mind around that idea.  Seems like the band would get in the way while heating.  Or do you just use the band after the wood is hot?   You have that method down "Pat" and I would love to learn it from you.
I did try steaming my osage stave for about an hour with no results.  Then I used the heat gun but it took a long time for it to start to bend, needed help to bend as needed, and then I had to work out the splinters on the belly.  The osage took a lot of work but it doesn't take as much wood to hold the bend in a static. 
On a subsequent hickory stave 3/4" thick it steamed for an hour + and took a great bend right off.  This was with my 60 degree recruve jig.

[Pat B]

Christopher, next time I bend tips I'll take some pics.