Author Topic: Metal strip tightening for bending recurves?  (Read 8625 times)

0 Members and 1 Guest are viewing this topic.

Offline Knoll

  • Member
  • Posts: 3,016
  • Mikey
Re: Metal strip tightening for bending recurves?
« Reply #15 on: February 19, 2018, 04:39:11 pm »
Nice technique, BJ.
I, and likely many others, have had same split along that longitudinal grain at end of caul. I have not tried it, but maybe glued plywood scab on both sides spanning split?
 
« Last Edit: February 19, 2018, 04:44:17 pm by Knoll »
... alone in distant woods or fields, in unpretending sproutlands or pastures tracked by rabbits, even in a bleak and, to most, cheerless day .... .  I suppose that this value, in my case, is equivalent to what others get by churchgoing & prayer.  Hank Thoreau, 1857

Offline bjrogg

  • Member
  • Posts: 10,701
  • Cedar Pond
Re: Metal strip tightening for bending recurves?
« Reply #16 on: February 19, 2018, 04:51:09 pm »
Nice technique, BJ.
I, and likely many others, have had same split along that longitudinal grain at end of caul. I have not tried it, but maybe glued plywood scab on both sides spanning split?

Knoll I'm sure that would be the best. I think a bolt would possibly work to and not be as wide.
Bjrogg
A hot cup of coffee and a beautiful sunrise

Offline Marc St Louis

  • Administrator
  • Member
  • Posts: 7,869
  • Keep it flexible
    • Marc's Bows and Arrows
Re: Metal strip tightening for bending recurves?
« Reply #17 on: February 19, 2018, 06:05:41 pm »
The strap is self tightening the way I do it

Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline DC

  • Member
  • Posts: 10,396
Re: Metal strip tightening for bending recurves?
« Reply #18 on: February 19, 2018, 06:24:51 pm »
Marc, do you boil/steam the strap and the bow tip?

Offline Marc St Louis

  • Administrator
  • Member
  • Posts: 7,869
  • Keep it flexible
    • Marc's Bows and Arrows
Re: Metal strip tightening for bending recurves?
« Reply #19 on: February 19, 2018, 08:00:49 pm »
Yes both are steamed together
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline bjrogg

  • Member
  • Posts: 10,701
  • Cedar Pond
Re: Metal strip tightening for bending recurves?
« Reply #20 on: February 19, 2018, 08:14:21 pm »
Marc do you just bend it by hand and hold it? That's a very nice bend.
Bjrogg
A hot cup of coffee and a beautiful sunrise

Offline Badger

  • Member
  • Posts: 8,118
Re: Metal strip tightening for bending recurves?
« Reply #21 on: February 19, 2018, 08:46:03 pm »
  That is really cool mark and simple! In the future that is how I will do it.

Offline DC

  • Member
  • Posts: 10,396
Re: Metal strip tightening for bending recurves?
« Reply #22 on: February 19, 2018, 11:30:56 pm »
My sentiments exactly :D

Offline gfugal

  • Member
  • Posts: 746
Re: Metal strip tightening for bending recurves?
« Reply #23 on: February 19, 2018, 11:58:12 pm »
The strap is self tightening the way I do it


I'm having a hard time figuring out which way is up and down haha. But I like this method, if only I had a Vice. Do you secure the curved form to the vice before you tighten it, if not I imagine you need a third hand i  the allotted time to keep everything in position as you tighten it.
Greg,
No risk, no gain. Expand the mold and try new things.

Offline Chief RID

  • Member
  • Posts: 684
Re: Metal strip tightening for bending recurves?
« Reply #24 on: February 20, 2018, 04:48:52 am »
Now that is a mystery pic. What is on the other end of that bow? I guess a rope tied to a truck bumper.

Offline Selfbowman

  • Member
  • Posts: 2,904
Re: Metal strip tightening for bending recurves?
« Reply #25 on: February 20, 2018, 07:50:52 am »
I've only built about 4-5 but I have always used dry heat in the process. You have to be careful and patient though or you will get a splinter or a crack across the grain. Arvin
Well I'll say!!  Osage is king!!

Offline Badger

  • Member
  • Posts: 8,118
Re: Metal strip tightening for bending recurves?
« Reply #26 on: February 20, 2018, 08:07:18 am »
  I have a bigger problem with my curves not being smooth than lifting splinters. Marks method looks pretty fool proof.

Offline Marc St Louis

  • Administrator
  • Member
  • Posts: 7,869
  • Keep it flexible
    • Marc's Bows and Arrows
Re: Metal strip tightening for bending recurves?
« Reply #27 on: February 20, 2018, 08:31:27 am »
The recurve form is screwed into the vise so it doesn't move.  After steaming the tip plus strap for about 15 minutes per each 1/4" of thickness,  it's inserted into the opening between the vise and form, set before-hand to be just the right size, and clamped down snug and then the curve is bent in.  This of course is done in as little time as possible, which is very little since my steamer is right next to the vise.  The other end of the bow, billet in this case, is supported by a stand, of which you can only see the base in that pic, and tied off so I don't have to sit there and hold it till it cools.  Also the support is at the same height as the tip so no twist is introduced 

As to prepping the recurve before steaming.  I work the tip to one growth ring and also into a very shallow D section on the belly side, plus I sand the edges.  I find that by doing it this way there is less likely hood of splinters lifting

Now that is a mystery pic. What is on the other end of that bow? I guess a rope tied to a truck bumper.

If you need a truck to hold your steamed bow/billet then you are doing something wrong.

P.S.  In case anyone can't figure it out, this picture is taken from above
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline Knoll

  • Member
  • Posts: 3,016
  • Mikey
Re: Metal strip tightening for bending recurves?
« Reply #28 on: February 20, 2018, 10:11:16 am »


Often good good solutions are simple ones. Or seem simple in retrospect.
Thanks for the picture!
... alone in distant woods or fields, in unpretending sproutlands or pastures tracked by rabbits, even in a bleak and, to most, cheerless day .... .  I suppose that this value, in my case, is equivalent to what others get by churchgoing & prayer.  Hank Thoreau, 1857

Offline DC

  • Member
  • Posts: 10,396
Re: Metal strip tightening for bending recurves?
« Reply #29 on: February 20, 2018, 10:32:45 am »
I see him, he's up in the top left hand corner!! ;D ;D