I’m a brand new owner. My GF arrived on Friday, and by Saturday I was making my first print. I was using the medium draft board provided, and all cuts were going super well! I was so excited that it was running so beautifully. I ran into troubles the second day, however. On Sunday evening, I tried printing through .1/4" Baltic birch plywood. All the materials I had used up to that point were 1/8" proofgrade provided. While I would love to be able to buy all materials from GF, it is not economically feasible, and I would very much like to cut through 1/4" or 3/8" for projects. I chose “uncertified material” and placed .25" in the parameters asked and the cut didn’t go through. It didn’t even touch the other side. I tried again using “thick plywood” under proofgrade options to see if that would change anything, and it didn’t cut through either.
Last night I read through the community forum, so this morning I tried to troubleshoot on my own. I cleaned all of the lenses, despite its being new. I went through the process of printing the gift of good measure steps. I used a digital caliper and tried the print again, this time putting in the exact thickness of the material. I tried printing a simple circle, but again it is not cutting through at all. Not even close. I can cut through proofgrade 1/8" draftboard and 1/8" Baltic birch plywood, but no luck with non-proofgrade 1/4" plywood. I know it’s possible. At least I hope because I don’t want to be limited to only proofgrade and only 1/8". I’m guessing it’s a settings issue that I am not comfortable or familiar with yet. Can someone please help me?
All of the machines cut easily through 1/4" woods, (assuming they are uniform and not vuggy or loaded with plugs of Bondo), you just aren’t using the right settings.
Start with a Proofgrade setting for the SAME THICKNESS material (so the Thick Proofgrade plywood would work for 1/4" material), then use a Test Cut to try out the settings. If it doesn’t quite make it through, slow the speed down in increments of ten points and keep running test prints until it does.
Write down those settings and use them in the future for similar material.
(Most plywoods aside from Proofgrade materials though can have knots, vugs, and thick glue plugs in them…try to place your design to avoid them. I really don’t like using most of them.)
Thicker-than-1/8" plywoods are notoriously inconsistent in how well they work with a laser cutter.
All those inner layers are great places to hide horrible quality wood, filler, and use a lot of glue to make it all stick together. Glue pockets and knots will behave very badly. Worse, poor quality plywood can have good sized voids in them which are highly optimal to starting fires.
What @Jules said; you’ll need to experiment until you get the cut you want.
One tip? If you not sure of the quality of a particular make of plywood, rip a bunch of strips with a table saw or circular saw. That way, you can have a look at the cross section of the wood across a number of areas. Check for voids, filler, knots, etc… That will give you a good idea of what to expect with that grade and brand of material.
This is a quick photo of an exposed edge of plywood on one of my garage workbenches. You can see just how inconsistent those middle layers are. At best, this would cut with some massive flareups. Given how broken up that 2nd to bottom layer is, I suspect this stuff is also full of glue. It would behave horribly on a laser cutter.
Welcome to the group. I’ve cut 3/8 Luan on the GF, so you don’t have any worries there. I don’t think we can give setting here in the category, but just as @Jules stated, slow the speed down some and test it out.
Support can’t help you with non-Proofgrade materials, but fortunately there are many existing discussions and settings shared in the Beyond the Manual forum. 1/4" BB is very common and easy to work with, as is the Lauan underlayment mentioned above.
Play around, but focus height was key for me. Setting it to .23 , full power 115 speed works most of the time. I’ll still hit a hard spot and need to finish it off by have sometimes. If I go slower the flashback gets pretty bad. (im on a pro)