Dusty Residue... How do YOU reduce the amount left behind?

[Shawn Handley]

Greetings,

Well, I have yet another reverse engraved project to do with Rowmark's Reverse Laser material but this time it is black. This means that all of the residue dusting left behind is very noticeable.

My question is how do we reduce the amount of dusting left behind when raster engraving?

I use two passes but each time, it leaves just a little bit of dusting behind inside the engraved area.

I have tried with and without the air assist on during raster.

I am 100% focused (triple checked) all the way through the project.

I will provide you with any info you might be curious about.


Please help :) I have a couple days to figure this problem out.

[Scott Shepherd]

I engrave black reverse almost every day. Haven't seen any issues with it leaving residue in the engraving, well nothing a static free cloth won't wipe off. Are the letters large?

On that material it also helps to be out of focus, not in focus, in my opinion.

One thing that will help on any material is to engrave from the bottom up, rather than the top down.

[Gary Hair]

I agree with Scott about bottom-up engraving. I sometimes do two passes on some colors, one at normal speed to do the actual engraving and a second at higher speed to do the cleanup. I clean the surface with dna and they turn out great. If you have too much residue on the surface then you are using either too much power or too little speed. Go with 100% speed and adjust power to get the results you need.

If I don't want to run something twice then I'll use Simple Green for cleanup. Put the pieces in the sink, spray with SG and let them sit for a few minutes. Wipe off with a non-scratch pad and they come out spotless.

Gary

[Shawn Handley]

Ok, I tried a lower power setting and maxed out the speed to 100%, dropped the table down just a bit (1/8") to put it out of focus and engraved bottom up, but now it wont even cut through the small coloured layer.

Next I tried the same thing but used a speed of 100% and a power of 80% twice. It came out quite nice on the sample with no residue.

I don't know my new 50 watt machine too well but this is in excess of what I would have used for settings with my old 25 watt Epilog Summit machine.

What do you think?

[Scott Shepherd]

I'm running about 30% power, 100% speed on a 45W, running is as if the material was about .090" thick.

[Shawn Handley]

I'm running about 30% power, 100% speed on a 45W, running is as if the material was about .090" thick.

Wow! Significantly less than mine. Do you do two passes?

[Gary Hair]

dropped the table down just a bit (1/8") to put it out of focus and engraved bottom up, but now it wont even cut through the small coloured layer.

I think you dropped it too far out of focus. For mine, I don't even change focus. I laser first pass slow and second pass fast. If I do take the laser out of focus it's usually only about .03 at the most. 1/8", .125, is about at the very end of the focal range of a lens and you'll find, as you did, that there's not much power left there.

It's hard to say what your 50 watt laser would need compared to my 30 watt, but I would probably try 100% speed and 80% power on the first pass and lower it to 50% power on the second. The only purpose of the second pass is to remove the residue and that won't take much power at all.

Gary

[Scott Shepherd]

Wow! Significantly less than mine. Do you do two passes?

Depends on the job and graphic. Sometimes I do, most of the times, I don't. Small text is one thing, large graphics and large text is another.

On larger areas, for the most part, I have stopped using that material and use alternative methods to produce the product.