6mm Plywood, cutting problems on Epilog 40 watt Zing.

[Peter Berry]

Hi Guys,
I have bought some very good quality 6mm Birch plywood, but am having great difficulty cutting it, I have used the Epilog setting of 20% speed, 100% power and 500HZ frequency, this setting takes three passes to cut and the wood is very charred and burnt, I have tried my own settings but to no avail.

After trying many settings I am down to 10% speed 100% power and can do it in two passes but the charring is still very bad.
Any help would be appreciated.

Regards
Peter

[Craig Matheny]

Peter I hate to say this but 6mm on a 40 watt is asking it to do a lot.... We cut 3mm all day long at 20 sp 100% pwr and 1500 Hz and no burnt edges or bad output. The biggest issue you have is the glue and what the grade ply you buy and where you buy it.

[Peter Berry]

Thanks for the reply Craig, looks like I bought a very good grade, I bought it from my local hardware shop, whereas in the past I have bought from a large DIY store and their ply was poor quality when rastering but did cut very well. Back to the drawing board.

[Joe Pelonio]

I agree with Craig, I cut it at speed 8 on 45 watt and it does OK but that's as thick as I can go. It's extra work but you can cut doubles out of 1/8" and glue them up.

[brian fithian]

I cut 1/4" birch everyday with my mini24 40w. It will cut a hole that you that you can just put a needle through. I use a speed of 8 at 100 power, i have got some plywoods that burn and char. They look almost like it has a styrofoam filler between two veneer layers. Not sure exactly what it is but it burns pretty bad.

[Craig Matheny]

I cut 1/4" birch everyday with my mini24 40w. It will cut a hole that you that you can just put a needle through. I use a speed of 8 at 100 power, i have got some plywoods that burn and char. They look almost like it has a styrofoam filler between two veneer layers. Not sure exactly what it is but it burns pretty bad.

Brian I can not see cutting anything at a speed less than 20 let alone a speed of 8 and try to make money doing it maybe that is why most of us say it can not be done

[Chad Fitzgerald]

Im cutting 1/4" Bbirch at .7speed, 60p, 100ppi. no charring, very nice edge. Jealous thaqt you guys are cutting at 8-20 speed.
Be careful not to get plywood with "lumber core", they are god awful to try to cut. A good deal od lumber yards often carry the "lumber core".
chad

[Michael Hunter]

I think that Craig has hit the answer.

You don't want "good quality", you want LASER quality ply.

Places do sell "laser ply", but normally charge an arm and a leg for it.
Timber merchants won't recognise "laser quality", but will sell you Interior Grade ply which has a (non-waterproof) laser friendly glue.

Interior grade is available in all the normal surface finishes - I normally buy B/BB - , so the only thing you miss out on is water resistance.

[Craig Matheny]

Im cutting 1/4" Bbirch at .7speed, 60p, 100ppi. no charring, very nice edge. Jealous thaqt you guys are cutting at 8-20 speed.
Be careful not to get plywood with "lumber core", they are god awful to try to cut. A good deal od lumber yards often carry the "lumber core".
chad

Chad no need for jealousy you need to remember we are on Epilogs and the speed thing is different not necessarily faster

[Peter Berry]

I think that Craig has hit the answer.

You don't want "good quality", you want LASER quality ply.

Places do sell "laser ply", but normally charge an arm and a leg for it.
Timber merchants won't recognise "laser quality", but will sell you Interior Grade ply which has a (non-waterproof) laser friendly glue.

Interior grade is available in all the normal surface finishes - I normally buy B/BB - , so the only thing you miss out on is water resistance.

Thanks Michael, what is B/BB ?

[Michael Hunter]

B/BB means (approximately)-

B Only very small knots and marks allowed, no dead knots and few if any repair patches.
BB Larger knots allowed, but no dead knots. Repair patches allowed (so many per square metre- can't remember the number).

Outside the professional furniture industry and a very few VERY expensive suppliers, grade A faced birch ply does not seem to be available in the UK.
The best grade in a typical UK DIY barn is usually BB/C (i.e. the reverse side can be pretty bad) and will normally be boiling water proof (phenolic glue - makes a dreadful mess when lasered) or moisture resistant (very hard to get a clean cut).

[dave cox]

Hi Peter, being down under we don't get the same plys as you can but I find if it is for exterior use forget about it, must be the glue but smoke is the order of the day.

[Mark Maslonkowski]

I had a similar problem recently trying to cut 6mm what I thought was top quality Baltic Birch Ply with my 60 watt. It said it was BB and I had similar unusable charred edges. Went to my hardwood distributed bought a true 5x5 panel of BB cuts like a dream.

Mark

[Steve Kelsey]

I cut 6mm all the time on my 40W epilog. I use 12/100 and do not get too much charring. I would recommend making sure everything is super clean. Check all your mirrors and lenses. If mine stops giving me a good cut I just give a quick clean and am back in action. It is surprising how much residue build-up you get when you are working with wood.

[Peter Berry]

I cut 6mm all the time on my 40W epilog. I use 12/100 and do not get too much charring. I would recommend making sure everything is super clean. Check all your mirrors and lenses. If mine stops giving me a good cut I just give a quick clean and am back in action. It is surprising how much residue build-up you get when you are working with wood.

Steve, thanks for the reply, what are your other settings ie: DPI and frequency?

[Steve Kelsey]

Steve, thanks for the reply, what are your other settings ie: DPI and frequency?
12s/100p/500f are the settings I use for vectoring.

[Neal Schlee]

Hi Guys,
I have bought some very good quality 6mm Birch plywood, but am having great difficulty cutting it, I have used the Epilog setting of 20% speed, 100% power and 500HZ frequency, this setting takes three passes to cut and the wood is very charred and burnt, I have tried my own settings but to no avail.

After trying many settings I am down to 10% speed 100% power and can do it in two passes but the charring is still very bad.
Any help would be appreciated.

Regards
Peter

Some high quality european birch ply (EuroBirch) is made with a phenolic based adhesive (an exterior water proof glue) and does not laser cut well where as Russian Baltic Birch uses an interior type adhesive and cuts well.

[Peter Berry]

Thanks Neal and everyone else for their help, I have given up now, I can cut 8mm MDF like a "knife through butter", but not this particular plywood, I have tried multiple passes and many settings but the edge is still charcoal.

[Michael Kowalczyk]

Most likely it is exterior glue being used or it could be a Chinese version that uses Poplar for the core. True Baltic Birch will cut clean and have brownish edges. Once in a while you will get a black poof of smoke and it won't cut all the way through... It seems, in my opinion, that they (the russians) are stacking the center core with less than BB grade and they are a little more prevalent in knots than normal. OK for CNC and mechanical cutting but not as nice for laser when cutting lots of small items.

[brian saban]

I always heard running at 100% power is bad for the laser and eats up the tube very quickly. Any truth to that?

[Keith Winter]

Trotec recommends 80w for 1/2, other posters are correct that's too thick for the wattage.

[Craig Matheny]

Most likley it is true I replace my tubes about every three years 40 and 60 watt epilog run 8 hours a day 6 days a week so about 7200 hours of run time. just warrentied out my last tube i just got 1y 9 m. old