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Main Boards => The Bowyer's Bench => Topic started by: bigbob2 on May 19, 2024, 04:26:10 AM

Title: Steam bending
Post by: bigbob2 on May 19, 2024, 04:26:10 AM
One for the self bowyers. At what  stage do you apply steam bending when dealing with Osage stave , and think I know the answer to this next bit , but can stave be exposed to steam maybe twice if dealing with an ornery stave that might require fair bit of work?
Title: Re: Steam bending
Post by: Pat B on May 19, 2024, 11:06:01 AM
I usually go after floor tiller stage but it depends on what sort of bending I am doing. For adjustments or a slight reflex I use dry heat(heat gun) and cooking oil. For more drastic bending like for recurves I would use steam and make sure the heat penetrates well before bending. Yes, at least in my experience, you can steam more than once if necessary. On dry wood I like to seal the back of the stave with shellac. Shellac can take the heat and moisture from the steam and still seal the back where other sealers can't. Sometimes when steaming dry wood the back will check as it dries so sealing the back I think is a necessity. I keep a can of spray shellac on my work bench all the time for such occasions.
Title: Re: Steam bending
Post by: bigbob2 on May 19, 2024, 06:12:46 PM
Thanks Pat. Exactly the reply I hoped for.Stave has propeller twist and deflex so think a good session in steamer will help. It is a very dry stave too.
Title: Re: Steam bending
Post by: Pat B on May 19, 2024, 10:28:59 PM
Looking forward to the results.  :thumbsup:
Title: Re: Steam bending
Post by: bigbob2 on May 19, 2024, 11:30:13 PM
Couple early photos here. Have to reduce limbs yet. Deflex might be visible in them as well as propellor twist . Sure I will get it aligned but might take more than one steam job.
Title: Re: Steam bending
Post by: bigbob2 on May 19, 2024, 11:33:07 PM
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Title: Re: Steam bending
Post by: Pat B on May 21, 2024, 08:14:34 AM
From where you are in these pics I would use a heat gun, cooking oil, a form with small wedges and clamps. If you look back at some of my build alongs I go step by step, with pics how I do this.
Title: Re: Steam bending
Post by: Mo_coon-catcher on May 21, 2024, 11:35:10 AM
I agree with every Pat said. Steam for steep curves and thicker pieces for me. You can do quite a bit to Osage with dry heat. I need to find the pictures and form, but I’ve bent a 3/4” thick piece of Osage into a 20” wide U shape with a 8” long flat in the handle with just a heat gun. Once Osage gets hot enough it bends like hot plastic. Once you have it in shape and position you want, give it a light scorching on the belly. I rarely have more than 1/8” of rebound when unclamping this method.

Like Pat. To get that stave into shape I would just use a heat gun then clamp and wedge it into shape. I like to do the bending and movement after floor tillering if it doesn’t line up at all, or if it’s close but not the shape I want the. I’ll brace up the stave, and even it out at brace, then heat bend with dry heat or steam.

Kyle
Title: Re: Steam bending
Post by: bigbob2 on May 21, 2024, 06:20:47 PM
Thanks guys. I will say I go have experience in using steam on previous bows. I was mainly concerned with possibly having to do more than one go due to the nature of this stave. I will attach photo of last bow. Definitely go with heat gun initially . Thanks for your joint input., appreciated. [ You are not allowed to view attachments ]  [ You are not allowed to view attachments ]
Title: Re: Steam bending
Post by: bigbob2 on May 21, 2024, 06:25:17 PM
Please delete duplicated photo.  [ You are not allowed to view attachments ]
Title: Re: Steam bending
Post by: bigbob2 on May 31, 2024, 12:40:51 AM
Thought I would show the progress J have made on the gnarly stave. Just got to floor  tiller stage and tips are now in alignment so, happy about that . Start wright reduction and tillering next day or so . [attachment=1[v [ You are not allowed to view attachments ]  [ You are not allowed to view attachments ]  [ You are not allowed to view attachments ]
Title: Re: Steam bending
Post by: bigbob2 on May 31, 2024, 12:43:01 AM
One more.  [ You are not allowed to view attachments ]