Author Topic: Flipping the tips post glue up  (Read 1656 times)

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Offline Kidder

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Flipping the tips post glue up
« on: November 23, 2021, 02:58:38 am »
Wondering what the collective thoughts are on trying to flip the tips of a bamboo backed bow post glue up with EA40? I saw that Carson did this with a boo yew on his BOM back in 2015. I believe that was with urac 185. Thoughts?

gutpile

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Re: Flipping the tips post glue up
« Reply #1 on: November 23, 2021, 09:49:01 am »
perry reflex... works nice and hold reflex.. good luck.. gut

Offline Hamish

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Re: Flipping the tips post glue up
« Reply #2 on: November 23, 2021, 05:08:14 pm »

Certain glues like urac and resorcinol have a long track record of working with heat bending.

I've never tried it with EA-40, so I don't know. I would think it to be a high risk situation, unless someone else chimes in with actual experience.

I have used heat guns to release joinery glued up with hardware store epoxy. Its a lot of work but you can get the joint to release.

Bamboo rod builders sometimes use heat to tweek the straightness of a rod blank. I read it works with Urac and resorcinol, but the author said the epoxy has memory and goes back to the original position after it cools down.

You're not going to really know until you try it. If you do just be prepared you will be risking all your previous work and materials invested.

Personally I wouldn't touch it, if its already an OK bow. If you want a bamboo backed bow with recurves, make another one and glue them in from the get go.

Offline mmattockx

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Re: Flipping the tips post glue up
« Reply #3 on: November 23, 2021, 06:59:35 pm »
You're not going to really know until you try it. If you do just be prepared you will be risking all your previous work and materials invested.

Personally I wouldn't touch it, if its already an OK bow. If you want a bamboo backed bow with recurves, make another one and glue them in from the get go.

+1 to both. Before doing it on a bow I would be gluing up a test piece from scraps and even then it is likely only an approximation of the bow in question. I think it is a way better choice to leave the bow as is and make another of the new design with that in mind from the start.


Mark

bownarra

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Re: Flipping the tips post glue up
« Reply #4 on: November 24, 2021, 02:15:35 am »
Depends on the mix used with the EA40. If you do the 2A - 1B mix AND cure at high temperature you can get away with heating. However not enough heat to recurve the tips!
The only safe way to do this is to run some saw cuts up the tips (side to side not back to belly!). Add enough kerfs and then fill them with thin pieces of wood prepared to exactly the kefr of your saw.
Then use a form and glue to set the whole thing.
This method works if you must add recurves.

Offline Marc St Louis

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Re: Flipping the tips post glue up
« Reply #5 on: November 24, 2021, 09:32:52 am »
Wondering what the collective thoughts are on trying to flip the tips of a bamboo backed bow post glue up with EA40? I saw that Carson did this with a boo yew on his BOM back in 2015. I believe that was with urac 185. Thoughts?

You're kidding right?  :)
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

gutpile

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Re: Flipping the tips post glue up
« Reply #6 on: November 24, 2021, 09:46:01 am »
so I read this wrong... POST GLUE UP.... not a good idea... flip when gluing is how I do it.. gut

Offline Pat B

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Re: Flipping the tips post glue up
« Reply #7 on: November 24, 2021, 10:21:31 am »
You can add a couple of layers of tip overlays to bring the tips up a bit but only a little. It's best to plan reflex or recurves before glue-up.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline Kidder

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Re: Flipping the tips post glue up
« Reply #8 on: November 24, 2021, 11:45:15 am »
Wondering what the collective thoughts are on trying to flip the tips of a bamboo backed bow post glue up with EA40? I saw that Carson did this with a boo yew on his BOM back in 2015. I believe that was with urac 185. Thoughts?

You're kidding right?  :)

Ha! Wish I was now that you’ve chimed in! Like I said I’ve seen it done with urac 185 on here so that’s what got me thinking…

Offline Kidder

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Re: Flipping the tips post glue up
« Reply #9 on: November 24, 2021, 12:19:43 pm »
And to prove I’m not a total joker here is where the idea/question came from…
http://www.primitivearcher.com/smf/index.php/topic,53121.0.html
And yes, they aren’t significant recurves but they have been done post glue up nonetheless.