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Main Boards => The Bowyer's Bench => Topic started by: Dave Bowers on March 22, 2013, 09:11:00 PM

Title: Heat Straightening
Post by: Dave Bowers on March 22, 2013, 09:11:00 PM
Hiya fellas, its been awhile since I've been in my shop. I have a question about straightening staves/bows with heat. All my wood is dry...roughly 2 years dry. I have a few roughed out that need straightening and I'm assuming dry heat for those?
But my other question is for the staves; (which are dry also)? Straighten before roughing them out, or wait till they're a bit shaped?

Thanks in advance
Dave
Title: Re: Heat Straightening
Post by: DVSHUNTER on March 22, 2013, 09:21:00 PM
Shape em a bit. It makes it easier to heat straighten.
Title: Re: Heat Straightening
Post by: Dave Bowers on March 22, 2013, 09:49:00 PM
Thanks DVS, I've read so many different theories it starts getting confusing.
Title: Re: Heat Straightening
Post by: David Flanrey on March 22, 2013, 09:56:00 PM
Dave,
What kind of wood you got there?  How thick are the staves?  Reason I ask is because your staves probably are not as dry as you think.  If they are osage, I doubt it.  Take the bark and sapwood off and down to a ring and seal up the back with some wood glue and let them dry some more in the house or somewhere dry.  If they are still a little moist when you put the heat to them they will check (crack).
Title: Re: Heat Straightening
Post by: Dave Bowers on March 22, 2013, 10:11:00 PM
Dave, mostly hickory and some maple. All my wood has had the bark taken off and sealed a while ago. Can't really give a gauge for thickness...as they all range? But if I have too guess maybe 1.5x1.5 for most?
Title: Re: Heat Straightening
Post by: Pat B on March 22, 2013, 10:51:00 PM
Dave you will have better luck with steam for the hickory. Get the stave at least to floor tiller stage so you don't have so much wood to move. I think I would seal the area to be steamed with shellac to help prevent the stave from taking on moistyure while steaming. Shellac can take the heat and moisture.
Title: Re: Heat Straightening
Post by: Dave Bowers on March 23, 2013, 11:30:00 AM
Pat, I think steam is what I'm gonna do. Just took it off the clamps from last night and dry heat produced very little change.
Thanks for the tip using shellac, I wasn't aware of that. Stay tuned we'll see how it goes.
Title: Re: Heat Straightening
Post by: D on March 23, 2013, 10:23:00 PM
Not to highjack the tred but how do you steam it???  Just hold it over a pot of boiling water or something??  I've never tried it but have some hickory that I'm wanting to flip the tips on.
Title: Re: Heat Straightening
Post by: Pat B on March 23, 2013, 10:54:00 PM
When I did it I use a large pot on our kitchen stove. Place the area to be bent or straightened over the pot and cover with aluminum foil making sure to wrap it around the sections of the bow that lang over the pot so the heat doesn't come up around the pot and scorch the bow. You will need to boil it for 1/2 hour to 45 minutes then, quickly get it clamped on the form before it cools.
Title: Re: Heat Straightening
Post by: D on March 24, 2013, 11:50:00 PM
Oh ok thank ya Pat.
Title: Re: Heat Straightening
Post by: Pat B on March 25, 2013, 08:32:00 AM
Have everything ready when the wood is ready to work. You will have less than a minute to get it clamped.
Title: Re: Heat Straightening
Post by: Grey Taylor on March 31, 2013, 09:54:00 PM
What would you use to heat straighten yew, steam or dry heat?

Guy
Title: Re: Heat Straightening
Post by: Pat B on March 31, 2013, 11:28:00 PM
Dry heat works well with yew.
Title: Re: Heat Straightening
Post by: Grey Taylor on April 01, 2013, 12:31:00 AM
Thanks, Pat. Once I get this stave further reduced I'll give it a go.

Guy
Title: Re: Heat Straightening
Post by: Pat B on April 01, 2013, 10:04:00 AM
Get it to at least floor tiller stage. The less wood you have to bend the easier it is to bend.