greenhorn bending oak trouble

[IndianKid]

So, first off, let me say thank you to everyone who is involved with this forum!
Would be a heck more scary If there wasn't people who hadnt been there already ..


So done with tillering and wanted to bend the limbs a little near the knocks, made a jig
Heat gun wes going while I had the knock tight in the clamp and heard the faintest cracking noise,
I saw the belly had a hair line crack in the stiff last 4 inch portion ...
It was only 1/16 in if that, and a itsy bit of sanding took it out.

Next side I figured i would heat more with a lighter weight (tied a 12" scraper) and just used light finger pressure...

Now heard the noise again ; (

My lack of experience is telling me that it's ok, I can push some
tight bond in but it just plain sucks....

If I had brushed with water wile heating would  it have happened?
Any suggestions on what to do from here ?

[bubby]

You will probably lose most of that when u ROUND THE EDGES, which you shoud do before you bend it, after two attempts with dry heat you are probably thinking steam works better with oak and you'd be right 
Red oak can be bent into big old recurves, but i dont have much luck with it

[bushboy]

Rounding of your edges like the size of a small pea will go a long way in preventing that!also a wet cloth with tinfoil over it and heating,gradual hand pressure pushing the bow towards the desired shape and clamping in place last.not to much pressure, you will feel the wood start to give in. About 7 minutes or so.let it cool and lock in place by "Slowly"heating the area, watching closely for fissures starting open up from moisture in the wood.the stave has to be quite dry or it most times cracks from dry heat.good luck!

[bushboy]

I. Should add that I havn't tried this on oak.i have with ash with meager results, but it bends osage well and elm like butter.

[IndianKid]

Ok, oak use steam and more radius on the edges ! Got it!

[Sidewinder]

I like to use some type of organic oil like peanut or lard or something like that to keep my wood hydrated and to prevent scorching. Also important is that you get a slow deep heat and don't put too much pressure on the bend until the wood starts to plasticize. I think most woods have a certain temp that will allow them to get a little rubbery and bend where you want them to. Just because it will bend does not mean your not forcing it. I have done this too. I agree with the above posts. Rounds the edges. Sand it down. The wood does need to be cured for dry heat.  A good rule of thumb  I use is if its green wood steam it if its cured wood dry heat. I almost always just use cured wood now a days so I don't have to steam much anymore but those are good things to remember.  Danny

[IndianKid]

I actually thought about using oil, but I wanted to use Tru oil to finish it
and wasn't sure if it would be compatible ...

Also, I'm not trying to be a know it all, because I'm just learning but I thought steam
Would work better on cured lumber and dry heat on green...

I assumed to bend needed heat and moisture, since my wood was 13%-15% dry heat
would be enough... i should have checked the moisture content
Right before steaming as I have a hunch that it was quite a bit lower
In the thin sections... I'm thinking steaming may have helped to prevent the cracks
as the additional moisture may have helped the wood fiber strech but
Again, this is my second bow and have tons to learn

[bubby]

In my experience with red oak dry heat is not it's friend

[Jim Davis]

I've made a lot of bows over the last 17  years or so, but only one red oak. The sealer is drying on it right now.

This was a stave I cut two or three years ago. It had a small kink in the middle, so I laid it out from center to each end (out of line with  each other but straight from each end to the middle.)

When the limbs were well along in the floor tiller stage, I heated the handle where the kink was. I used dry heat (don't tell anyone,  it was a propane torch!) with the bow forced more than straight. When it seemed to be relaxed pretty much into the forced shape, I left it to cool overnight. In the morning I took it out of the vice and it had kept just the right amount of straightening.

As  for recurving  or "flipping" the tips, I quit bothering with that 15 years ago. Too little  to gain and too much to lose.

Jim Davis