Glue formwork plywood?

[Boolean]

Hello, I suspect I made a mistake. I was going to make my own guide rail for my old circular saw and followed the instructions that a helpful person on this forum linked to.

The instructions said to glue two boards like masonite to create a straight edge for the saw to run along.
I had an old "formply" board left over from a casting job and it seemed perfect.

However, after two days the wood glue hadn't dried between the boards and I suspect the surface coating (phenolic resin) is disrupting the drying process?

Has anyone tested gluing this material?

Should I simply wait longer or is it hopeless? The glue dries as well as in the bottle - that is, not at all? 🤓

 

[sinuslinus]

Ordinary wood glue/white glue (PVAc) relies on the material being absorbent. If you're going to glue coated boards, you need to use a mounting adhesive/installation glue.

 

[Boolean]

Hello, I suspect I have made a mistake. I was going to make my own guide rail for my old circular saw and followed instructions linked by a helpful person on this forum.

You were supposed to glue two boards like masonite to get a straight edge for the saw to run along.
I had an old piece of “formply” left over from concrete work and it seemed perfect.

But, after two days the wood glue hadn't dried between the boards, and I suspect the surface coating (phenol resin-coated) is disturbing the drying process?

Has anyone tested gluing this material?

Should I simply wait longer, or is it hopeless? The glue dries as well as it does in the bottle - that is, not at all? 🤓

Regular wood glue/white glue (PVAc) relies on absorbing materials. If you’re going to glue coated boards, you have to use some contact adhesive/assembly adhesive.

Okay, so it’s not worth waiting a week?
Maybe drill "air holes"?
I'll chalk this up to the learning account 😂

 

[ÅkeSun]

The thing about formply is that nothing is supposed to stick to the surface, especially not cement. The surface contains a release agent, so glue doesn't work either...
But can't you just screw the boards together?

 

[Boolean]

Yes, it's my backup plan.
Thank you so much to both of you for the help!

 

[sinuslinus]

Ok, and there's no point in waiting a week?
Maybe drill "airholes"?
I'll have to put this on the "learn-account" 😂

No, it will be the same problem if you try to glue together two painted pieces of wood.