Best way to go about cutting 1/4" ply

Hey guys, so brand new GF parent here making my post debut lol. Loving it so far and having fun figuring things out. Also love what an amazing community has come along with it. So much great inspiration and information to sift through.

As for my question…
I was wondering the best way to go about this. Im making signage letters that need to be 1/4 thick ply. My first idea/test was to glue two full sheets of 1/8 PG ply together (using gorilla wood glue) THEN cutting the letters out of that to get the 1/4 thickness. Its 10 letters and I wanted to avoid having to line and glue them all up individually.

I tried many different variations of speed and multiple passes while changing the focus height along the way. It seems though, the best way I’m able to get through it is with a single pass @ 120/full but I get a lot of char. I was setting the focus height to 0.25. Next I’m going to try just grabbing a piece of already 1/4 ply from the store and just see if its any easier to cut through. I really love the finish of the PG though so thats why I was trying to go the sandwich route.

Figured I’d fish for some ideas from you GF gurus on cutting 1/4 and what settings work best.

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I’ve been having problems with 1/4" BB plywood myself. Try multipass and see if that helps.

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Gluing 1/8 PG together and cutting sounds expensive. And you’re no closer to ensuring they will cut through either.

I’ve been doing a lot of BB in 1/4" size. I use the Thick Maple Plywood setting and it comes out looking good. Make sure to mask your plywood. The times it hasn’t cut through have been due to an issue with the plywood itself (generally one of the inner plies having voids and too much glue or filler). Check that the piece is cut before moving it.

That’s my experience. YMMV

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The 1/4" ply from the hardware store is likely to be much harder to cut than the PG ply - most of that is really junky - full of voids and knots that are going to be hard to cut. (You just need to place around them if you can.)

Best bet is to pick up some thick PG ply (it’s 1/4") - they already have the settings, or the thick PG draftboard. I use that for a ton of stuff, it cuts very smoothly.

Next best bet is to pick up some Baltic Birch ply - it seems to be the best of the non-PG stuff.

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Baltic Birch all the way for something that will be visually inspected, you can get it at Rockler or online from many sources…

Or Woodcraft locally (if you have one) or Menards if they have those near you (not here in the East). Or a local wood store - not the big box HD or Lowes though.

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@Jules I thought the thick PG ply was only 3/16". Ya know what though, I think thats close enough and no one will know its only 1/16" narrower. I think its the gorilla glue thats making it so difficult to get through.

Since the consensus seems to be to just go through legit 1/4" ply, for this i’m just gonna pick up some thick PG ply. Makes life easier and I dig the finish the PG comes with.

Thanks for the supply suggestions. I’m in FL and havent heard of any of those but it looks like there is actually a woodcraft supply in my area. I already picked up some transfer tape so I’m definitely gonna try out the Baltic Birch for my nest project. Just gonna go with the PG for this one. Thanks for the help and suggestions!

def gonna try out the BB next time around and no dice on the multipass setting. Didnt seem to help much. I think the gorilla wood glue is too tough to get through.

One of the things @dan has mentioned several times over the course of this forums existence that I’ve been meaning to do homework on is total internal reflection and how that applies to certain materials (wood, acrylic) and the co2 laser wavelength.

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I’d imagine that the gorilla glue (is that the, get it damp and it expands stuff?) interferes with that process, beyond just being additional material to cut through - if you’re interested in specifics…

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After working with 1/4 BB I have realized how incredibly valuable PG ply is. The amount of re-cuts I’ve had to do with offbrand BB would have paid for the PG twice over. 1/8 BB ply cuts relatively more consistently.

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I am cutting the 1/4" BB at 140/high but there is probably 1/64 left that needs to be cut through the back side. I have already decreased it to 120/high but it looks like it didn’t fix it entirely. should I actually change a different variable before I mess this up