Warning! Do not use carpenters glue on PG materials

I should of known better. I had problems earlier with a nifty business card holder which I tried to glue with carpenters glue. It failed at the glue line. I sanded the finish off the cherry PG material and glued up again. I burned the mystery box parts and used very thin cyano glue on the drawer and outer case. It wicked into the joints and the glue bonded very well. Thought I should try carpenters glue on the reminder of the parts. Looked great until I set it down on an end table and the pieces fell off the outer box. I will purchase some thick cyano glue and try again.

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Been using it for over 40 years, and on laser cut parts from PG material without issue. Sounds like operator error.

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Carpenters glue will not stick to the finish on PG materials. It peels off like a second skin.

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Yes, so like any material with an existing finish, you sand it a little before applying glue. That applies to any kind of material.

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If you are using carpenters glue on the burned edges it will work because there is no finish there. However trying to glue a small PG strip to a PG box is another story.

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While efly can be a bit blunt he is correct, I use tightbond all the time you just need to sand the gloss off first. Nothing wrong with CA eather.

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Sanding those little strips on the top and bottom of the mystery box would be tedious. I will try the cyano.

I have always used CA glue & works well with me I use Hobbybond Thick & Thin. I use the thick for more application control & thin when I don’t have to have control.

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This is good advice. Wood glue doesn’t stick well to finished wood and not everyone knows that. And, yes, sanding the joints is tedious and not always precise. It’s far easier to just use a different glue if you have it.

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Just read through the thread, thank you for the heads up. I’m learning from scratch…

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I’ve settled on using UHU glue (the solvent based in yellow squeeze tube, not glue sticks)
Sticks to all the lasered things.

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Wood glue works great as a mechanical connection and not very well to smooth hard surfaces. CA glue is strong but creates a frosted white around where it is used, also damages acrylic. Acrylic glue can do a great job on acrylic but not so much bonding acrylic to other materials. Knowing which glue goes best in which situation is its own rabbit hole.

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