Rowmark 1/16" - Engraving & Cutting - settings for 80W Shenhui

[Khalid Nazim]

I might be getting my first order to engrave equipment tags. The size of the tag is 6" x 1" and I am planning to do it on 2 ply 1/16" Rowmark. Customer has supplied the logo and I would like to remove all material on the top layer except where the logo & text is to give it a raised look. Then I would cut a rectangle around the whole logo+text. Any ideas for the settings to use on a Shenhui 80W?

Regards

[Dan Hintz]

Settings should be determined for all new materials on the mchine being used (all laser cartridges are different)... run a power grid and see what's best. It should take you five minutes and use a few square inches of material. With that much power, you'll be running at 100S and probably less than 30P.

[Tony Lenkic]

Khalid, do not use lots of power when removing large area. Plastic will warp under intense heat.
As Dan said, test it on your machine.

[Khalid Nazim]

After 4 tries got the right settings and it came out fantastic. For engraving, it was 20% power and 100mm/s speed. For cutting, it was 50% power and 80mm/s speed. Also, I was getting too much residue during the engraving/cutting. I then switched off air assist and voila no residue!

[Rodne Gold]

100mm/s is very slow , I would up power and speed to 300mm/s - try to get to the higest speed you can asd your thruput increases. The coaxial air assist thru the nozzle tends to slatter residue all around , we made a small tube and directed air assist outside the nozzle to the cutting point blowing down and across it and it's perfect , lens stays clean and almost no residue spatter. We closed the hole in the nozzle , also allows easier lens cleaning. I use a LOT of air assist - kinda almost blast it , the wimpy compressor that comes with wont cut it , you need a lot of air.

[George M. Perzel]

Khalid;
Will send stuff tomorrow. Jobs like the one you mentions where the majority of material is being removed are usually not very profitable due to the amount of engraving time required, the warping which Tony mentioned, and the generally poor textured surface which results unless dpi is very high-taking even longer to do. Much easier to cut raised area out and glue it to another surfgace.
Best Regards,
George
Laserarts

[Khalid Nazim]

Rodne,

I tried with your suggestion of speed/power and the time is now reduced in half. Can you suggest a air assist compressor for a single machine like I have?

George:
I changed the idea of removing all that material. It was wrong thinking. I am just doing the regular engraving.

All
I tried with a red top over white base rowmark and it came out perfect. However, the customer wants a white top over green and when I engrave on this sheet, there is too much green residue thats flying around and ruining the tag. I am using any air assist as it worsens the situation.

So is there any way to clean the residue to salvage the tags that I have made?

I am also using masking tape on the sheet and increasing the power of the laser and that is helping but still a bit a residue built up is still happening. Any suggestions on how to clean this up.

Regards

[Rodne Gold]

Try cleaning off the residue with benziene or naptha - most hardware/paint shops will have it , also try methylated spirits. Even maybe a household mild abraisive cleaner cream like handy andy would work. Not sure of what you need as a compressor , we have this massive 3 phase one , about 10 hp , but it supplys air to 8 lasers , cnc machines and other tools - not sure whats available in england , but the other forumites can help better.

[Hilton Lister]

Some Forum Users recommend spraying with WD40 before lasering plastic. Works for me, but then I use mainly Gold/Black.