heat treatening deflex part of the limb?

[lonbow]

About one year ago, I cut a nice piece of laburnum wood. Unfortunatelly, the stave has a punctual deflex bend in the middle of one limb. Might it be possible to use heat treatening for keeping it straight, even when the bow is strained? And if it works - should I then use heat treatening for the entire bow? I´ve already tried steam bending with an other laburnum bow (no heat treatening afterwards), but the limb mostly came back to its original shape again.

thank you in advance and greetings,
lonbow

[SLIMBOB]

I know little about that wood specifically, but in general yes you can straighten a kink in a limb.  I will do it with a heat gun once I have the limb bending good but while there is still wood yet to come off in tillering.  Mine will typically hold that shape. I temper the entire belly at that time as well.  Not completely sure this translates entirely to Laburnum, but it is my guess that it will.

[Marc St Louis]

No idea how Laburnum reacts to heat-treating/dry-heat bending.  I would be inclined to use wet heat first with localized steaming to get the kink out and then temper the wood

[lonbow]

Thank you for the replies! So I will steam the deflex part at first and then I will do some heat treatening on the entire bow! I will probably  not put some reflex into the limbs because the bow will have a setback and slightly recurved tips. So will the steambent part of the limb go back to its former shape again when I apply heat on the limb or will I have to fix the limb at first?

[SLIMBOB]

If you are going to steam it first and then heat temper afterwards, I would strap or clamp it to a form first.  Nothing to elaborate is needed, just a shaped 2x4 for example.  That will keep it from moving on you and losing ground.  Curious how sharp the kink is?  Is your tiller complete or do you still have wood to remove?  Pics are always helpful.

[lonbow]

The bow is still a stave, but I'd like to start building the bow in two weeks when I'm going to be at home again. I will post some pictures then. The stave has actually two more kinks but they are reflex, so I don't think that the bow can change its shape there when bent.

[SLIMBOB]

Well, not sure exactly what you mean by that.  You can straighten reflexed spots and deflexed spots with heat, wet and or dry.  Once they are set with tempering mine typically hold their new shape.  When I was a yonker I would just work with whatever mother nature gave me in a given stave....until I realized I didn't have to.  That by heating and bending I could manipulate the wood so that I could establish some symmetry between the two limbs.  Much easier to tiller and more pleasing to my eye.  If your still at the stave stage then the world is your oyster in shaping it to your liking.  Post pics before you start and you will get all kinds of advice.  Then just pick the route that pleases you.

[lonbow]

Thanks for your help slimbob, I will post some pictures of the stave when I'm back home!

[penderbender]

I've got a nice piece of laburnum too. Never worked it so I'm gonna follow this. It's beautiful wood. Post pics and good luck! - Brendan

[lonbow]

Thank you penderbender! I'll post some pictures when I'll build the bow. I've already made two laburnum bows and I am convinced that laburnum is not of minor value than yew and osage! The sapwood is extremely elastic and I love its contrast to the heartwood. It's a dense wood, but it feels about as soft as yew when plaining it. My plan is building my second swiss bow (often refered as burgundian bow).
I would be very happy if you could also post pictures of your progress 😉