Laser cutting plywood

[Thomas Hempleman]

Has anyone out there ever had any kind of good luck cutting plywood with your laser? I spent the better part of today trying to get a decent cut on 1/8" maple plywood with my 30 watt LaserPro Mercury. Now I admit, this is not the ideal wattage to be cutting wood. But I adjusted speed, power and PPI and still got a lousy charred cut or else it didn't cut all the way through. The laser will cut solid wood like a charm. But it just doesn't like glued up plys. I have read through the Sawmill threads and it seems everyone agrees plywood and lasers just don't get along when it comes to vector cutting. I'm ready to just forget about plywood and use solid wood sheets from now on, except plywood is so much cheaper. And being frugal (cheap?), I hate to spend the extra bucks. If anyone has had good results at laser cutting thin plywood sheets, please post your settings. Thanks!

[Rodne Gold]

We use light density fibreboard (ldf) and have it veneered both sides or single side and cut that , its stays nice and flat and is not too expensive , much cheaper than real wood and it cuts well. The secret is to use a low density fbreboard , not Mdf.
1/8th works ok , 1/4 seems too thick.the great thing is that you can offer exotic finishes etc quite cheaply and it looks like real wood , can be engraved well too.

[George M. Perzel]

Hi Tom;
I've had fairly good luck cutting up to 3/8" plywood with a 60 watt Laserpro unit, but you do tend to end up with charred edges. Cut the ppi down to about 150 and run about 1% spped and 100 Power. I usually use Baltic/Finnish birch as it tends to be uniform in structure than ordinary ply and remains fairly flat. Also air assist and good exhaust is mandatory to minimize burning.
Failure to cut thru in all areas is usually due to change in composition in the material (voids, knots, glue,etc).
Good Luck

[William Capman]

Hi Tom,

I make a line of 3D dinosaur puzzle from 1/8 Baltic Bird plywood for my craft shows. Baltic Birch normally cuts very well (on my 45 watt TT at 14 speed, 100 power) and leaves a very nice brown edge. On occasion, I will run into a sheet which has knots or small voids between the plys which will not cut through. If the uncut section isn’t too large I can usually score the area with a knife and break it out without damaging the part. It doesn’t happen very often but when it does it can be frustrating

[Dennis Kotlowski]

Tom,

For some projects I use a Duro wood (like the stuff LaserBits sells). I get it from Home Depot. They have it in 1/4" thick pieces 24"x48" and they sell it for $3.69 ea. sheet. It laser cuts very good. I use it for animal puzzles and clocks that I am going to paint.


Dennis

[John LeBlanc]

Tom,

For some projects I use a Duro wood (like the stuff LaserBits sells). I get it from Home Depot.

Just got back from our Home Depot. I asked one of the fellows there if he could point me to where they had the stuff. He looked at me like I was an alien. (I seem to get that these days.) Oh well. Maybe it's only available in some stores. Thanks for the tip-- I'll keep looking!

John

[Thomas Hempleman]

Thanks for the info, folks. Unfortunately, my customer wanted his project made out of maple, so I had to use the maple plywood. I did finally get the project cut but it was slow at 100% power, 2% speed and 200 PPI. Even at those settings, I ended up making two passes to get all the way through. The edges were black and I had to clean them off. The kerf was just slightly narrower than the Grand Canyon. I'll try the Baltic birch ply and see how that works. In the future if a customer wants a specific wood, I think I'll use solid sheets rather than plywood. The cut is much cleaner and faster.

[Killor Perez]

Hello,
The problem is plywood glues used.
Behave like mirrors to the signal of the IR laser,Then we need much more energy to cut.
The urea glue, adsorbs better laser radiation, and cut more easily.
That the phenolic glue, commonly used in plywood for exterior use.

[Marc Myer]

Do you glue the veneers yourself? Sounds like a great idea; I'd like to try that. Is the ldf strong?


We use light density fibreboard (ldf) and have it veneered both sides or single side and cut that , its stays nice and flat and is not too expensive , much cheaper than real wood and it cuts well. The secret is to use a low density fbreboard , not Mdf.
1/8th works ok , 1/4 seems too thick.the great thing is that you can offer exotic finishes etc quite cheaply and it looks like real wood , can be engraved well too.

[Matt A. Peterson]

Hello,
The problem is plywood glues used.
Behave like mirrors to the signal of the IR laser,Then we need much more energy to cut.
The urea glue, adsorbs better laser radiation, and cut more easily.
That the phenolic glue, commonly used in plywood for exterior use.

I agree. The black colored glue used in commercial plywood does not cut well with a laser. If you notice the glue used on the laser friendly plywood, it's white in color. Unfortunately, you almost have to special order it, or buy it from a laser supply house, to get your hands on it.

Matt

[Dave West]

Although not the maple you need, I use model grade lite plywood available at most hobby shops. I believe it's an Italian Poplar ply. Lightweight and cream colored, both 1/8 and 1/4 inch cut like a dream on my 25 watt.

Dave

[Joe Flores]

Hello,
testing one 2 three

[Bill Cunningham]

Hello,
testing one 2 three

Hmmm reading you 5 square.. Although the 'S' meter on this old computer is a bit stingy ..

[Michael Hunter]

Not infallible, but asking for "interior" (as opposed to "exterior") grade plywood is more likely to get plywood which cuts easily.

As Killor and other have said, it is the glue between the plies which makes the difference between clean cutting and a smutty mess.

[william kaminsky]

Has anyone out there ever had any kind of good luck cutting plywood with your laser? I spent the better part of today trying to get a decent cut on 1/8" maple plywood with my 30 watt LaserPro Mercury. Now I admit, this is not the ideal wattage to be cutting wood. But I adjusted speed, power and PPI and still got a lousy charred cut or else it didn't cut all the way through. The laser will cut solid wood like a charm. But it just doesn't like glued up plys. I have read through the Sawmill threads and it seems everyone agrees plywood and lasers just don't get along when it comes to vector cutting. I'm ready to just forget about plywood and use solid wood sheets from now on, except plywood is so much cheaper. And being frugal (cheap?), I hate to spend the extra bucks. If anyone has had good results at laser cutting thin plywood sheets, please post your settings. Thanks!


Well, 30 watt on 1/8" plywood is sort of marginal. Have used 50-100 watt and got charred edges. That was running speed very slow too.

To get through in one shot is not always easy. Best thing is that you need more power. I tried a 35 watt unit on 1/8" plywood and some 1/4" plywood. (it charred as expected) but the cut was rather wide. I have also (vector) cut the plywood using 100 watts and the cut is near thin as possible too. Was getting a kerf of .015" to .020" on the 35 watt, and about .008" on the 100 watt. That is per line, not per part. Double the number if thinking per part.


Wm.

[Andy Selley]

Not infallible, but asking for "interior" (as opposed to "exterior") grade plywood is more likely to get plywood which cuts easily.

As Killor and other have said, it is the glue between the plies which makes the difference between clean cutting and a smutty mess.

just to confirm what has been said. I cut ply on my 1000 watt laser. We use interior BB grade ply. The interior glued plywood is suitable for laser cutting, exterior glue can ignite! and is therefore NOT suitable. I hope this may clear up any queries

[Duncan Crawford]

Thomas,

I've had good luck with the maple/birch plywood from Lowes. It's 0.190 in thick, has relatively few voids, and will cut though on my 40 watt Epilog Mini-18 at speed 10, power 100, at 500 Hz. If you find a void on a cut edge, it can be filled using Timbermate or equivalent wood filler and colored with a black permanent marker before applying finish.

If I have a fine pattern to vector cut, or use transfer paper on unfinished wood to eliminate residue as on the sample shown, I'll slow to 8/100/500. Sample has maple side out on all pieces.

duncan

[Dan Hintz]

I cut ply on my 1000 watt laser.
Any posts after this is just showing off... ;)

[John Noell]

Over here we only get ply from local woods, so most of the nice looking ply is a wood called dakua makadre. The interior grade is glued with a PVA and cuts beautifully. The edges are not really brown, closer to beige. However, when you engrave it, the wood simply volatilizes and it looks like you used a metal tool to engrave it. We use the exterior ply with phenolic glue to engrave maps of Fiji and as you soon as you bust throught the thin cap you get a beautiful black mark. Great contrast. But do not try to cut the map out with a laser!

[Mike vonBuelow]

Concur that the Birch at Lowes is way more laser-friendly than their Oak !