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Bruce Clumpner
05-25-2010, 4:37 PM
I'm running my first set of plaques on JDS blue painted plates and have a question on what to expect. The process is leaving a slight blue tinge which I assume is some paint residue. I ran a sample first, testing a wide gamut of speed and power (epilog 35w) and all setting seem to leave this residue. It's not terrible, but you can still see a visible difference between lasered area and the standard unpainted border.

Can I clear it off with DNA or will that affect the remaining painted surface.

Any tips?

thanks.

Bruce

laura passek
05-25-2010, 4:57 PM
Hi Bruce
I just use a soft rag with soapy water ( wrung out) or for plastic I use a magic eraser made by Mr Clean
Good luck

Bruce Clumpner
05-25-2010, 5:05 PM
On the way to the sink now...
thanks

greg lindsey
05-25-2010, 5:26 PM
Bruce, cant speak for the brass, but on the alum plates, you can pretty much use whatever ( within reason, not acid) on them to clean, I have already bought and engraved 650+ alum344 full sheets so far this year. I engrave schematics for oil companies and believe me they put them through the harshest enviroments, from power washing to wiping down with old greasy rags and they hold up fine.

Bruce Clumpner
05-25-2010, 5:46 PM
Even with fairly hard scrubbing with a green-sided sponge. Maybe it's not residue, but incomplete burn-off.. My slowest pass was 35% speed and 100% power on my epilog, and it still left the tinge. Maybe I'll go slower, but at 5min/plate that would add significant time to the job.

Since they seem fairly durable, I'll try DNA and whatever else I have around to see what I can do. Any other magic formulas?

I'll try and scan the plate a bit later

BC

Mike Null
05-25-2010, 6:14 PM
Bruce

DNA will help clean and polish the brass or brass coated steel and I use it on all my plates but an incomplete burn will still be there. You need to adjust your settings just a little to solve that problem.

laura passek
05-25-2010, 7:05 PM
Bruce
try reversing your settings, I run painted Brass on a 50 watt at 100 speed and 30 - 35 power. the residue maybe because you are getting to much heat.

Bruce Clumpner
05-25-2010, 8:21 PM
I sacrificed two more plates to run some additional tests, The lower power thing looked promising but it was not cutting through the fine details well enough. But when I used two full power passes, that seemed to make a difference...Probably because of my low power machine, (35w) can't get enough power to remove enough at a high speed pass, and the heat builds up on a low speed pass. Will keep workining and post the results.

Gary and Jessica Houghton
05-28-2010, 5:39 PM
On our 35w Epliog we make our first pass at 40s/100p and then a second pass at about 60s/100p. It comes out clean and bright!

Viktor Voroncov
05-29-2010, 3:53 AM
We also use two pass engraving, from bottom to top, with more powerful than usual air assist

Martin Boekers
05-31-2010, 5:12 PM
You may want to check focus, alignment and make sure the sheet is laying completely flat. I've had sheets that had just the slightest bow and made for inconsistant results.

Also check for a dirty lense or mirror.

Marty