Cutting 1/4" Baltic Birch

I bought some 1/4" baltic birch that I can’t get to cut through right on my Basic. This stuff is either the hardest five ply, .24 inch measured board in the history of wood, or I’m doing something wrong. At one point, I followed the instructions I’ve seen on the forums and setup a 130 speed, full power… 3 PASS, and RAN IT TWICE and it didn’t cut through.

Any other material? Cuts just fine.

Looking for settings I should try to troubleshoot it.

Unfortunately, non-proofgrade plywoods can vary significantly in quality. Air pockets, glue plugs and sometimes even something like Bondo used to fill gaps in cheaper plywoods are not laserable. I’ve had some send up flames like Vesuvius, hit air pockets or knots and char without cutting through in five passes…you get the idea.

It’s sometimes possible to shine a really strong flashlight through the wood, find air pockets and then mark them, and try to place your design around the marks. But yeah, it’s a lot harder to cut. (You might get lucky and find something a little more consistent with a different source.)

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I just bought some 1/4” yesterday that I was cutting at 145/Full Power (Pro).

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I was afraid this might be the case! That’s a waste of not one but TWO plywood sheets I’ve chopped down to laser bed size :frowning:

Still, I supposed I can still engrave them but use something else for simple cuts…

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I got it to cut almost all the way through on a different piece of wood at 130/full, 3 passes. Still, it charred the heck out of that piece’s edges, where it’s not particularly useful for projects.

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I bought a couple each from different local hardware stores, was thrilled at how cheap they were, cut them down to use in the laser…and the cussing commenced. I think it’s a right of passage. :smile:

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Aww, That makes my heart hurt a little. And my wallet.

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You can still use it for “hidden” projects. Drawer dividers, box bases…that sort of thing. But yeah, I used it up as quickly as I could on prototyping and moved on to some better quality stuff for real.

Use it for the learning curve.

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You’re sure it’s baltic birch? What size were the sheets you bought?

If your sheets were 4’x8’, they weren’t baltic, that comes in 5’x5’. (edit: that was a dirty lie, it seems) Non baltic 1/4" ply can be a grab bag of crappy cuts.

Also, dumb question, do you have the focus set properly?

Is your lens in right side up? (easy to put it back in upside down)

When did you last clean your optics?

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The sheet was 4x8 and labeled baltic… clearly Menards doesn’t have the right stuff. :man_shrugging:

As for the “dumb questions” (that I totally ran aloud to myself as I was troubleshooting earlier)…

  • List item Focus was set at .24, where it should be. The one that cut through was actually accidentally set to .13, after I’d cut a 1/8" board to confirm that it wasn’t the overall power of the laser having an issue.

  • List item Optics were cleaned twice in the middle of this troubleshooting. Everything was installed right, then reinstalled right, then recleaned to make sure it was reinstalled right.

Thanks for letting me know I’m asking myself the right questions! :slight_smile:

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Pretty sure they are now making it available in 4x8’ also (the real stuff). But who knows… Russian birch should also have a stamp on it with Cyrillic lettering, I believe. But that also may depend on the manufacturer of it.

But…

Did you caliper it to get the .240” number? All of the Baltic birch I’ve bought has consistently been .240” but looking at the Menards site, they list actual as .180”.

https://www.menards.com/main/building-materials/panel-products/hardwood-panels/1-4-x-4-x-8-baltic-birch-plywood/1253100/p-1444441908454-c-13334.htm?tid=-8387453987960139727&ipos=13

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Ahh yes, I was calling it Plycarp before I got finished with it. Some places it actually cut fine, others not so much and it was a carp toss if I got anything or burned up some, or it was totally laserproof or both.

That said if you are using unshielded magnets that can affect the head fan and if the smoke is not quickly blown away it will go from smoke to flame, and any time you see that happening it will not be cutting as deeply as if it was not happening and of course you will have more char.

Some wood (Walnut, Maple, Paduk) you can cut through half-inch material, some nice woods like Zebrawood or most Mahogany can go in as one sort of wood but come out as ash (even Ash can be ashes) unless you are very careful. Most are in between.

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Measured with calipers at 0.24". Nothing stamped on it and it hasn’t tried to compromise anything except my patience, so I’m not sure what I seen to have here now.

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Oh my! That is a lot of cutting for such a piece of scrap!

I’m not sure what you mean by unshielded magnets. Magnets for what?

In my experience, 1/8" plywoods are generally OK as long as they are BB grade. But even BB grade 1/4" plywood is typically a complete and total roll of the dice as to what it might do.

1/4" is a heck of a lot of thickness to hide really crappy wood and a lot of glue filler.

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If you are not using them then that is not the issue. The wood needs to be absolutely flat and even a half millimeter difference from the laser to the work could cause a problem.

Especially when needing to hold down the middle using Neo-magnets is a strong temptation, but folk forget why an electric motor works and what happens with rapidly moving metals in a strong magnetic field and unless shielded the magnetic field can be quite powerful where the gantry and head fans are working. This was not understood by most of us until quite recently. :crazy_face:

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Yep. There is a domestic manufacturer and the Russians are exporting some as well. But you’ll not likely find it in a general purpose big box stores. And it usually requires a special order. A cabinet maker supplier might carry it but most still focus on the traditional Scandanavian supplied 5x5 stuff. I think Aircraft Spruce will special order it too (but then you have enormous shipping costs - not an issue if you’re building a plane but a bit much for crafting :slightly_smiling_face:).

Oh and it’s more expensive by a fair amount as well.

I doubt Menard’s is carrying real BB. The bright light test would show any dark pocket areas where you could take a saw to get a cross-section to find out what’s in there and if it ain’t birch veneer, it ain’t Baltic Birch & you can make a stink at the store. BB in qtr inch is 5 plies of birch veneer - no embedded knots, voids, glue pockets, Bondo or any other crap.

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A reminder that some people will abbreviate Baltic Birch plywood as BB ply (known core, no mention of grade), some folks will be talking about Baltic Birch plywood with a BB/BB grade (known core, graded eternal appearance), and some places may sell plywood made from birch with a BB/BB grade that is not Baltic birch (unknown core, graded external appearance).

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I gave up completely on cutting any plywood even 1/8". I will engrave them but as far as cutting I use my table saw, scroll saw or my chop saw. Less headaches & less money. I use only proof grade when cutting for my projects. As far as the proof grade cost I just factor it into my sales price.

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The Birch handi-panels Menards sells laser well at 155/Full (Pro). Sometimes they even have ones not modeled on a roller coaster. On long cuts there will be a bit here and there where those settings don’t go all the way through, but nothing a utility knife doesn’t fix. They aren’t pretty enough to use for display, unless heavily coated in paint, but are affordable for utility items and interior filler in stacked assemblies.

They are advertised as 1/4", but even in the store are often labeled as 3/16".

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