Author Topic: Joining Backing strips  (Read 2407 times)

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Offline Marc St Louis

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Re: Joining Backing strips
« Reply #15 on: February 25, 2018, 01:27:42 pm »
Am I seeing an extra layer in there Marc. I see the two backing strips and then a continuous layer and then the billets. Is the middle one an overlay to strengthen the splice? Do you steam the ends of the backing strips?

It is a power lam and I always use them on spliced bows.  I use dry-heat on Bamboo and localized steam for Maple.
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline Aaron H

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Re: Joining Backing strips
« Reply #16 on: February 25, 2018, 03:12:45 pm »
Marc, is your power lam spliced also, or is it one piece?

Offline Aaron H

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Re: Joining Backing strips
« Reply #17 on: February 25, 2018, 03:23:08 pm »
Put a 45degree angle on your but joints and glue together with super glue. The angle can be achieved by a 1x2cut on 45 then put your laminate next to the 1x2 and grind your angle on a belt sander.   Arvin
Wouldn't this be considered a scarf joint?

I guess so but no matter the name would it not work. After all it's just to hold it together during lay up of the bow correct? Or maybe I misunderstood the?.   Arvin

Yea, absolutely it would work.  Just wanted to make sure we were all on the same page. 

Offline Marc St Louis

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Re: Joining Backing strips
« Reply #18 on: February 25, 2018, 03:48:37 pm »
Splicing the power lam would defeat its purpose
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline Springbuck

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Re: Joining Backing strips
« Reply #19 on: February 26, 2018, 05:17:27 pm »
  DC, Here is one way that worked for me when I just needed a bit more length.

 I either mill a handle block to a deflexed angle or glue up several 1/4" or 3/8" lams of the same wood into a deflexed curve.  ))), like that.  Add  your core, or do your butt-splicing like Marc showed.  Power-lam if you plan on it. 

The backing can then be glued on with a gap of up to several inches (@ 4" was my biggest), between them depending on how deflexed the whole thing is.  You grind the front flat which tapers down the backings just at the tips.  Then slap a couple of front overlays on to round out the handle.

If the backing has it's full thickness well inboard of where the fade-outs end, you'll be fine.  It's held by several well glued down inches AND sandwiched by the overlays, and supported by the powerlam.

 It's worked for about 6 bows for me, so far.
« Last Edit: February 26, 2018, 05:30:09 pm by Springbuck »

Offline Springbuck

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Re: Joining Backing strips
« Reply #20 on: February 26, 2018, 05:34:32 pm »
backing ends at the yellow arrow.  Fade on the belly ends at the blue arrow.  Power-lam ends at the red arrow.