Author Topic: Perry reflex glue up . . . progress  (Read 13045 times)

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Offline Knoll

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Perry reflex glue up . . . progress
« on: February 04, 2015, 11:20:22 pm »
Here's the clamping setup.


Here's the result.



Done a bit of woodworking and these are the worst gluelines I've ever seen!  Bow length is 66" and used 20 clamps, including 2 at riser area.  So there was about 3" between clamps. 
Glue was TB2.  Used this in past gluing risers and glue-on recurve tips.  Never had anything like this happen.
Limbs are approx 1 3/4" wide.  Wooden blocks placed on backing beneath each clamp ... blocks were 'bout 1 1/4" square.
Thought clamps were tight.
Only section of limbs with decent bond was 6-8" length at tips.

Wanna make another effort, but first . . . . . . . Any ideas re likely culprit/culprits? 
« Last Edit: February 07, 2015, 11:38:29 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 Blaflair2

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Re: Perry reflex glue up . . . FAIL!
« Reply #1 on: February 04, 2015, 11:26:56 pm »
Get some old bike tire inner tubes, clamp and wrap, then clamp to shape
Nothing ventured nothing gained

Offline bubby

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Re: Perry reflex glue up . . . FAIL!
« Reply #2 on: February 04, 2015, 11:33:28 pm »
Yup tubes are the way to go, just don't wrap them too tight
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline Knoll

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Re: Perry reflex glue up . . . progress
« Reply #3 on: February 04, 2015, 11:34:45 pm »
As long-time cyclist, have tubes galore!
« Last Edit: February 07, 2015, 11:39:17 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 Chadwick

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Re: Perry reflex glue up . . . FAIL!
« Reply #4 on: February 04, 2015, 11:37:27 pm »
Clamps also work. Especially as many as you used. Was the glue visibly getting squeezed out along a thin line? I'm guessing that the materials didn't match up, somehow.
Nothing flying, Nothing dying

Offline Blaflair2

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Re: Perry reflex glue up . . . FAIL!
« Reply #5 on: February 04, 2015, 11:42:51 pm »
Also if u wanna use clamps I rip a piece of wood a little narrower than the backing, and cover it with painters tape for a pressure strip
Nothing ventured nothing gained

Offline GB

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Re: Perry reflex glue up . . . FAIL!
« Reply #6 on: February 04, 2015, 11:48:58 pm »
I use clamps, too, about 30 of 'em and a 4 foot 1/8" thick aluminum bar for the center.  Before glue up, I hold the backer and belly lam together and put it up to my shop light to check for gaps.  Have to make sure both surfaces are perfectly flat.  I'll either run it through my belt sander again or hand sand with 60 grit down the center of both lams to make certain there are no crowns anywhere.
Yeah, I remember when we had a President who didn't wear a tinfoil hat.

Offline bubby

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Re: Perry reflex glue up . . . FAIL!
« Reply #7 on: February 04, 2015, 11:56:37 pm »
Yeah clamps work, thats what the tubes are i use two clamps per bow
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline Knoll

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Re: Perry reflex glue up . . . FAIL!
« Reply #8 on: February 05, 2015, 12:01:50 am »
.... Before glue up, I hold the backer and belly lam together and put it up to my shop light to check for gaps.  Have to make sure both surfaces are perfectly flat.  ......
I didn't, but will in future!
... 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 rps3

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Re: Perry reflex glue up . . . FAIL!
« Reply #9 on: February 05, 2015, 12:12:36 pm »
Would it help to keep the backing strip not quite as wide as what you are gluing it to? Looks like it is just as wide or wider to me.

Offline bubby

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Re: Perry reflex glue up . . . FAIL!
« Reply #10 on: February 05, 2015, 12:16:33 pm »
Would it help to keep the backing strip not quite as wide as what you are gluing it to? Looks like it is just as wide or wider to me.




Sure does
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline Badger

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Re: Perry reflex glue up . . . FAIL!
« Reply #11 on: February 05, 2015, 12:29:09 pm »
  The moisture in the glue caused the wood to cup. I switched to inner tube wraps with maybe some additional clamping in fade areas if needed.

Offline DavidV

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Re: Perry reflex glue up . . . FAIL!
« Reply #12 on: February 05, 2015, 01:23:53 pm »
  The moisture in the glue caused the wood to cup. I switched to inner tube wraps with maybe some additional clamping in fade areas if needed.

Exactly this, the same thing has happened to me and it ended up being warped lams. Inner tubes are good because the put pressure along the entire back.
Springfield, MO

Offline adb

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Re: Perry reflex glue up . . . FAIL!
« Reply #13 on: February 05, 2015, 02:17:52 pm »
The backing strip is too thin to clamp directly to it. As mentioned, the moisture from the glue and uneven clamping pressure will cause it to deform. Use a clamping board on top of your backing strip, and use inner tubes to provide even pressure... plus they're WAY cheaper than 30 clamps. I get flat inner tubes from bike shops for free. They throw them away by the hundreds.

Offline dragonman

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Re: Perry reflex glue up . . . FAIL!
« Reply #14 on: February 05, 2015, 02:49:16 pm »
maybe the glued surfaces where not flat?, but rounded and high in  the middle?   I cant see what is wrong with clamps, never had a problem with them ( except expense ).....cant see how this  could occur if the 2 surfaces to be glued are exactlty flat
'expansion and compression'.. the secret of life is to balance these two opposing forces.......