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Mayo Pardo
10-04-2016, 9:50 PM
Working on some new product designs I tried a dull silver metallic posterboard from Hobby Lobby (from China).
I got a nice cut however with the silver facing up, the cuts have a foggy or sooty appearance surrounding the cut lines.
There's also a nice sparkler effect while cutting but I did have air assist on so there were no flare ups.

I then tried cutting with the silver facing down and although the results were better, the fogging was not totally eliminated.

Is this typically an issue with power/speed or do you think it's just the material properties?
I know I have to experiment with other settings but I thought someone here may have already had a similar problem and solved it.

I'll be trying other metallic colors in the next few days but I'd like to eliminate the problem before wasting more time and materials.
A damp towel helps remove most of the smoke from the metallic finish but I don't want to wipe every piece I cut.

Jiten Patel
10-05-2016, 4:09 AM
Generally it is a material problem. If it is a glossy coating, the soot created from the material sticks to it. You can reduce it by brushing the material afterwards alternatively try raising the material which helps a little. In our experience, gloss coated stocks don't really cut well without using transfer paper which become tedious and not worth the time or effort involved. There are plenty of stocks you can use which cut extremely well and still have a pearlescent quality such as Stardream.

Kev Williams
10-05-2016, 11:35 AM
Wiping soot & goo off laser cut parts is tantamount to deburring metal parts fabbed in a machine shop- it's just part of the process, and not a lot you can do about it.

John Blazy
10-05-2016, 1:19 PM
Why not mask the panel prior to cutting? Low tack tape should work, although I buy 750 foot rolls of Poly premask from Flexcon - real pricey, but I go through it and its light tack adhesive bonds well to any gloss coating and then peels off without residue from a laser cut edge. And its clear. I'm sure others will chime in on the best tape for laser for small jobs.

Joe Pelonio
10-05-2016, 7:46 PM
Why not mask the panel prior to cutting? Low tack tape should work, although I buy 750 foot rolls of Poly premask from Flexcon - real pricey, but I go through it and its light tack adhesive bonds well to any gloss coating and then peels off without residue from a laser cut edge. And its clear. I'm sure others will chime in on the best tape for laser for small jobs.
I agree with low tack transfer tape, but to avoid pulling up the edges of the top layer when removing, on poster board I'll apply it in two halves, overlapped in the middle. Then Peel it off sloooowly from the middle out.

David Somers
10-05-2016, 9:54 PM
I think the metallic coating is actually a thin mylar? For what that is worth.

And another bit of odd information that wont be helpful, but at least interesting. I tried applying faux gold and silver and copper leaf to BB ply and to veneers and it cut fine. There was a bit of residue on the cut edge but it came off with a cloth that was damp with mineral spirits

I would hate to apply faux gold leaf to an entire poster board. I do not have the degree of self abusiveness needed to do that.