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Bert Kemp
10-21-2015, 5:45 PM
OK searching back to Scotts 2007 post on this subject theres still a lot of maybe ok maybe not.
So being I'm not 100% certain of what I have but pretty sure its some form of poly-carbonate I'm going to try to engrave it. What I have is a window from an airplane I think:rolleyes: A friend and disabled Air Force Vet asked if I could engrave his name, dates of service and the Air Force insignia onto it for him. I have nothing to practice on so I have to get it right the first time so any help with settings on a 60 watt will be greatly appreciated.
Marking on this window say PPG Flexseal. I googled its says Laminated Safety Glass among other things.323763Thanks , I know you'll come thru for him.

Scott Shepherd
10-21-2015, 6:08 PM
Just start with low power and sneak up on it Bert. Not much else you can do on a 1 shot, never done it before type of material. You should be okay doing that.

I'd engrave some painters tape or a piece of posterboard taped to it first to check for location, then I'd start with light power and work up. That's how I'd do it, if I had to.

sean berry
10-21-2015, 6:49 PM
And start engraving at 0 power, or with a sheet of aluminum foil for placement.

John Noell
10-21-2015, 6:58 PM
If it's polycarbonate it might not come out very pretty. You might want to test a tiny spot along the edge.

Dave Sheldrake
10-21-2015, 7:02 PM
It's laminated Bert...I'd avoid it to be honest

Bert Kemp
10-21-2015, 7:09 PM
Dave are you saying its dangerous to do or just that it won't come out very good???



It's laminated Bert...I'd avoid it to be honest

Scott Shepherd
10-21-2015, 7:11 PM
Dave are you saying its dangerous to do or just that it won't come out very good???

My guess is that it's not going to come out very well, but some times you have to do what you have to do :)

Bert Kemp
10-21-2015, 7:22 PM
Well I'm going to talk with him and make sure he understands that it might not come out great. I can always get a nice piece of acrylic the same size and do that if I crash and burn on his window :eek:


My guess is that it's not going to come out very well, but some times you have to do what you have to do :)

Clark Pace
10-21-2015, 7:34 PM
I work with polycarbonate every day. Lexan is the brand. It will not laser cut. And yes it will not engrave very well either. It also smells terrible and puts off nasty fumes.

Joe Pelonio
10-21-2015, 9:47 PM
Every bus has polycarbonate panels in front of the seat next to the door, and if you look in the bottom corner, you will see the manufacturers information and specs engraved onto it, very clear, tiny letters. I'll look at one closely in the morning but probably can't tell if laser, and if so, it could be fiber or YAG. I have cut it cleanly with practice, but don't recommend it due to the yellow smoke and multiple passes. I have also not been able to get very small text to engrave well, but larger letters in a block font like Helvetica come out OK. Being from an aircraft window, it may not be anything close to the same formulation as the sheet goods, and it light be better to have someone do it with a rotary.

Bert Kemp
10-21-2015, 10:48 PM
yes this window has info engraved on it it was made by PPG Flexseal but I can't tell what engraved it either LOL


Every bus has polycarbonate panels in front of the seat next to the door, and if you look in the bottom corner, you will see the manufacturers information and specs engraved onto it, very clear, tiny letters. I'll look at one closely in the morning but probably can't tell if laser, and if so, it could be fiber or YAG. I have cut it cleanly with practice, but don't recommend it due to the yellow smoke and multiple passes. I have also not been able to get very small text to engrave well, but larger letters in a block font like Helvetica come out OK. Being from an aircraft window, it may not be anything close to the same formulation as the sheet goods, and it light be better to have someone do it with a rotary.

Kev Williams
10-22-2015, 3:03 PM
There's a sure fire way to tell if it's polycarb- laser it, just do a test engrave anywhere small along the edge, 20 power 80 speed should work. When I do tests like this I just use 9 point Arial bold and engrave "2015" in the most non-important place I can find....

Do the test-- If you get yellow smoke and stains, it's polycarb. If not, it's something else. Just make sure you used enough power in the first place! :)

It lasers fine, I engrave instructions onto the bottoms of polycarb measuring cups for a local customer all the time. But there IS always a yellowish stain left behind. DNA gets most of it off, but not all. My customer is fine with it, but for an area as large as you're attempting, if you find it IS polycarb, the results will be less than stellar...I'd consider light sandblasting instead.

If you don't get yellow, then check the engraving under a loupe and if you like what you see, give it a try...

Bert Kemp
10-22-2015, 4:08 PM
ok I did the test No yellow smoke no stain this is how it looks untouched .323842 ok why is it upside down :confused:LOL

Clark Pace
10-22-2015, 6:42 PM
There's a sure fire way to tell if it's polycarb- laser it, just do a test engrave anywhere small along the edge, 20 power 80 speed should work. When I do tests like this I just use 9 point Arial bold and engrave "2015" in the most non-important place I can find....

Do the test-- If you get yellow smoke and stains, it's polycarb. If not, it's something else. Just make sure you used enough power in the first place! :)

It lasers fine, I engrave instructions onto the bottoms of polycarb measuring cups for a local customer all the time. But there IS always a yellowish stain left behind. DNA gets most of it off, but not all. My customer is fine with it, but for an area as large as you're attempting, if you find it IS polycarb, the results will be less than stellar...I'd consider light sandblasting instead.h p

If you don't get yellow, then check the engraving under a loupe and if you like what you see, give it a try...


If you flick poly carb with your finger it sounds very different to acrylic. It has a high pitch twang. Also it's a little blue.

Joe Pelonio
10-22-2015, 8:36 PM
That's great!

Bert Kemp
10-22-2015, 10:06 PM
That may work ok on a single sheet but what I have is an airplane window, its 2 pieces about a 1/4" thick each with an air space between molded into a frame . very heavy. if you so call pluck it all you get is a dull thud.:D But anyway my test looks ok so I think it will engrave fine. We'll see when he figures out what he wants on it LOL


If you flick poly carb with your finger it sounds very different to acrylic. It has a high pitch twang. Also it's a little blue.

Kev Williams
10-23-2015, 12:13 AM
yeah, that test looked great, I think you'll be fine-- :)

Bert Kemp
10-28-2015, 1:31 PM
UP Date
Well I finally got the info from my friend about what he wanted on this aircraft window (still not sure what the material is) and I gave it a go this morning. I think it turned out OK. FWIW there was no smell at all, no smoke or yellow stain. I ran it at 350 mmps at 20% Power and a scan gap of .055324266mirrored the text so your looking thru 2 layers of what ever it is. LOL

Scott Shepherd
10-28-2015, 1:56 PM
That turned out great Bert! Good job!

Bert Kemp
10-28-2015, 2:03 PM
Thanks Scott can you guess what his Job was LOL :)


That turned out great Bert! Good job!

Scott Shepherd
10-28-2015, 2:18 PM
Thanks Scott can you guess what his Job was LOL :)


Official Window Looker Outter? :D

Gary Hair
10-28-2015, 3:02 PM
Official Window Looker Outter? :D

Official Stuff Disappearer...

Bert Kemp
10-28-2015, 3:32 PM
Nope:eek: sorry guess again.


Official Stuff Disappearer...

Michele Welch
10-28-2015, 5:33 PM
Great job Bert!!!