Author Topic: are there some woods that will not heat-bend?  (Read 1400 times)

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Offline stuckinthemud

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are there some woods that will not heat-bend?
« on: April 13, 2017, 03:24:01 pm »
I've been trying to straighten out a piece of laurel.  First I tried dry heat - played the heat gun up and down the section for way longer than usual and it wouldn't move.  Weird thing is that the belly-side was too hot to touch but the back was still cool - like the wood wasn't conducting the heat.  Next up steam - bow on the big pan with a foil hood, 20 minutes of good hot steam, nothing, no bending at all.  The wood wasn't even too hot to touch - and this steaming rig has bent everything I ever tried up til now. When I get an hour next I'll try boiling it, but, am I wasting my time?  Are there some woods  you cannot heat-bend?

Offline Pat B

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Re: are there some woods that will not heat-bend?
« Reply #1 on: April 13, 2017, 03:49:15 pm »
Many tropical hardwoods won't bend with heat.  I've never tried laurel. Is this a laurel tree or like mountain laurel(Kalmia sp.). Have you cut this stave to almost bow size? The less wood you have the easier it bends.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline Dances with squirrels

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Re: are there some woods that will not heat-bend?
« Reply #2 on: April 13, 2017, 03:53:00 pm »
Sounds like you didn't have it hot enough on either attempt. Heat gun it on all sides until you can't wrap your hand around it... then a minute or two more. Wood is a very poor conductor. It takes a little time for the heat to fully penetrate.

On a stave 3/4" thick, I generally steam for an hour.
Straight wood may make a better bow, but crooked wood makes a better bowyer

Offline Pat B

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Re: are there some woods that will not heat-bend?
« Reply #3 on: April 13, 2017, 03:55:14 pm »
You can put down vegetable oil on the wood first then use the heat gun. I think it helps distribute the heat better and holds it longer and helps prevent scorching.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline stuckinthemud

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Re: are there some woods that will not heat-bend?
« Reply #4 on: April 13, 2017, 03:57:35 pm »
I think its Prunus laurocerasus (common/English laurel); the stave is a little over-size as I haven't decided on whether to go flat-bow or D-bow, but its still only 1.5" wide and 3/4 thick at the crown - it is high crowned, the edges are about 1/4 thick

Offline Lucasade

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Re: are there some woods that will not heat-bend?
« Reply #5 on: April 14, 2017, 03:18:05 am »
I don't know about bending it but prunus laurocerasus (I know it as cherry laurel) generates cyanide gas as it pyrolises so you may want to be working outside if you are subjecting it to a lot of heat.

Offline stuckinthemud

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Re: are there some woods that will not heat-bend?
« Reply #6 on: April 14, 2017, 07:40:33 am »
That's pretty scary, thanks for the warning

Offline Eric Garza

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Re: are there some woods that will not heat-bend?
« Reply #7 on: April 14, 2017, 11:29:05 am »
3/4 inches is a lot of wood to bend. I recommend deciding whether you're going to make a flat bow or a D-bow, and rough the limbs out to near-final dimensions. I've never attempted to bend more than 1/2 inches of wood. I also find flat bows much easier to bend than D-bows; the former is all I make now.

Offline dragonman

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Re: are there some woods that will not heat-bend?
« Reply #8 on: April 14, 2017, 12:07:01 pm »
a bit off the point , but does laurel make a good bow???....I just saw hundreds of laurel branches and stems leaning against a bank, left from clearing them out of some woods near to me.....they say they poison the soil with cyanide..I was wondering when I passed them if one would make a decent bow
'expansion and compression'.. the secret of life is to balance these two opposing forces.......

Offline stuckinthemud

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Re: are there some woods that will not heat-bend?
« Reply #9 on: April 14, 2017, 12:45:26 pm »
it makes a wicked fast bow, I would take everything long enough and wide enough to billet. Split it as soon as you can, but no problems seasoning it if you leave the bark on.

You all were right, it has straightened fine, just needed a lot more steam and a lot more time than normal.
« Last Edit: April 14, 2017, 02:56:29 pm by stuckinthemud »