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Adrian Hernandez
11-29-2012, 10:20 PM
I never had to remove the burnt edge from a laser cut in the wood; I have a project for Christmas and I would like to know if there is a chemical that I can use to remove the burnt edge. I am aware that I can sand the edges, but that is not an option for me, is there a way to accomplish this.

PS: Everyone’s help is greatly appreciated.

Sincerely,
Adrian

Mike Null
11-30-2012, 6:33 AM
Adrian

A picture would help. Usually the culprit is too much power or you're trying to cut wood that's too thick. Use air assist if you have it.

Dan Hintz
11-30-2012, 8:27 AM
Chemically? No. Prevention is the best method here... adjusting your settings or sanding are your only real options.

john banks
11-30-2012, 8:52 AM
With the right material (non-laser plywood seem the worst), good air assist and just enough power to cut cleanly through the edge can be a pleasant brown colour that doesn't look or smell burnt and needs virtually no clean up even without masking.

Todd Burch
11-30-2012, 9:03 AM
I had no idea wood could be laser cut and you don't see burnt edges. Guess I've always used the wrong person to do mine.

tommy suriady
11-30-2012, 11:47 AM
bought my new 1hp compressor, delivering 6 bars of constant pressure today.
tried it with a 12mm plywood. the wind assist was stoking the amber.
surface looked good, but the inside was glowing and when done, it was all charred. Hahaha.
I spent 450usd on that thing and was last using it to clean dusts off my equipments.
no effect on acrylics cutting.
gonna try further tomorrow...

Mike Null
11-30-2012, 11:54 AM
Tommy

12mm is pretty thick to be cutting with a laser. I would imagine you're going to get charring every time. I would cut in several passes with air assist but too much air will fan the flames.

Neil Pabia
11-30-2012, 1:26 PM
I have used a little bit of windex with a toothbrush to remove the marks, works well but is a pain to do.

George Brown
11-30-2012, 5:42 PM
bought my new 1hp compressor, delivering 6 bars of constant pressure today.
tried it with a 12mm plywood. the wind assist was stoking the amber.
surface looked good, but the inside was glowing and when done, it was all charred. Hahaha.
I spent 450usd on that thing and was last using it to clean dusts off my equipments.
no effect on acrylics cutting.
gonna try further tomorrow...

I cut quite a bit of wood, and with the right settings, the edge gets a nice brown or golden color. Air assist is a must, and you will need that compressor. Plywood is a whole different story. The glue in the ply can make it char and turn black. Also, I had some ply with internal plugs that would NOT cut, even tried burning through, turned it into charcoal, and some sections would still not cut. Also, 12 mm is pretty much at the max or beyond which you will get a nice edge. And at that thickness, you will get a tapered cut anyway. Next time I cut, I'll try a 1/2 inch ply and if it cuts ok, will post the numbers.

Kees Soeters
12-01-2012, 11:15 AM
Most of the burned color can be removed with Ammonia (i think, in english, it's called that way too)
Just spray it, let is rest for a short while and gently brush it of under water.. Dry it and, i think, 90-99% is gone.
Yes, Ammonia stinks like a chickenbarn, as lasered plywood does (which reminds me of smoked mackerel)

Kees

Craig Matheny
12-01-2012, 9:25 PM
I think we are talking an oxymoron here.... you are burning wood with high power and do not want the burnt or colored edges? First I cut 3mm Birch all day long and there is no way of stopping the burnt edge you can minimize it some but prevention nope it is part of the process Sorry...

tommy suriady
12-02-2012, 12:48 AM
I sometimes immerse plywood into water for a couple of minutes and then cutting them. works for something thin.
If I cut mdf, I just mop it with a wet cloth and kept spraying water as the laser works its way... seems to work without destroying the wood...

Adrian Hernandez
12-02-2012, 2:25 PM
Thanks to everyone for taking the time to answer the question; I'm replying and quoting three comments that sums up everyone’s advice.

I forgot to mention that I am cutting 3mm birch plywood......... Thanks Mike

I guess I can try new settings and see if I get different results. Too Comfortable with current settings; thus, NO CHEMICALS.........Thanks Dan

I am getting the nice brown edge on the cut. "Cut cleanly through the edge can be a pleasant brown color"......... Thanks John

The project is a mini grandfather clock with a pendulum movement as a Christmas present for my siblings.

Once again thank you for your time and consideration. I'll take everyone's advise and "go back to the drawing board".

Sincerely,
Adrian

Mike Lysov
12-02-2012, 3:03 PM
I think we are talking an oxymoron here.... you are burning wood with high power and do not want the burnt or colored edges? First I cut 3mm Birch all day long and there is no way of stopping the burnt edge you can minimize it some but prevention nope it is part of the process Sorry...

totally agree with Graig.

I have found a way to get rid of residue at the front and at the back of wood but I know it is impossible to stop edges burning.

Mike Lysov
12-02-2012, 3:12 PM
I sometimes immerse plywood into water for a couple of minutes and then cutting them. works for something thin.
If I cut mdf, I just mop it with a wet cloth and kept spraying water as the laser works its way... seems to work without destroying the wood...

Just increase air supply and make air supply nozle hole as small as possible and you won't get this residue at the front. No need to sand or spray anymore.

And if you raise material from a honeycomb table you will also get it clean on the back side of wood.

I was cutting MDF for 2 years and I had to sand it front and back from this rsidue and laser reflection marks until I realized that I can get clean cuts using just more air and by raising a panel. And with maximum air supply through a smaller hole I can cut 10-20% faster than with low pressure air through a bigger hole.

Martin Boekers
12-03-2012, 9:44 AM
Check to make sure lens, mirrors are clean and alignment is right on. These can degrade any project you do.

Rusty Fennell
08-15-2015, 10:11 AM
"Murphy's Soap" works very well and is made for and safe for all woods. Find at most any grocery store.


I never had to remove the burnt edge from a laser cut in the wood; I have a project for Christmas and I would like to know if there is a chemical that I can use to remove the burnt edge. I am aware that I can sand the edges, but that is not an option for me, is there a way to accomplish this.

PS: Everyone’s help is greatly appreciated.

Sincerely,
Adrian

Rich Harman
08-15-2015, 6:04 PM
Also, 12 mm... at that thickness, you will get a tapered cut anyway.

This is 3/4" oak, it's 50% thicker than 12mm. No taper. It was cut at 80W with a 2-1/2" lens.

Bert Kemp
08-15-2015, 6:48 PM
If your edges are burnt you don't have the correct settings. Your edges should be as stated before by other a nice tan or light brown color. You csn rub your finger on it and nothing comes off. if you get black on your fingers then you need to adjust your settings. lees power more speed. You want to cut as fast as you can with the lowest pwr settings and still cut thru. 3 to 4 mm wood should not burn . 6mm you might get some charring.



totally agree with Graig.

I have found a way to get rid of residue at the front and at the back of wood but I know it is impossible to stop edges burning.