What kind of platform/ grill/ table To eliminate backburn marks on acrylic?

[Miriam Ng]

I have a 50wredsail x700 laser cutter. My platform/table looks like a blade grill. I’mgetting backside burn marks on my cuts as I’m cutting acrylic. What’s the best way to eliminate back burn marks? What kind of grill/ platform/ table should Isit my material on? And what material should my grill/platform/ table be madeof? I heard about using cardboardhoneycomb, however I’m weary about smoke stains on my acrylic. Any help would be great. Thanks!

[Gary Hair]

There are a lot of things that can cause flash marks on whatever you are cutting.
1. Too much power - you only need enough to get through the material consistently, any more and you enhance the flash marks.
2. Reflection from the bed/grid - aluminum is the best choice, anodized black is the very best. Everything will reflect somewhat so you have to select a material that minimizes it. I have heard great things about using Corian, Keith has written posts about it.
3. Removal of the protective tape/film/etc. - leave the protective film on the back of whatever material you are cutting. If it doesn't have it to begin with then I'd suggest covering the back with transfer tape.

Cardboard honeycomb would probably make things worse, I wouldn't recommend it.

Gary

[Ross Moshinsky]

Pin tables are cheap and effective.

[Rich Harman]

I've been using a plastic "egg crate" light panel from Home Depot for smaller parts that cannot tolerate the little tick marks made by the laser reflecting off the edge of the honeycomb. When I cut large parts I use a bed of nails.

[Gary Hair]

Careful with that Rich - I used to use the same thing until it caught fire while I was lasering acrylic. Fortunately, I never leave the laser alone when cutting anything so I saw it right away and put it out before any real damage happened. Mainly just soot on the bottom of the acrylic and all over the bed. It will happen no matter how careful you are, the laser still has plenty of power after it goes through whatever you are cutting and has just enough power to melt and ignite the panel.

Just FYI

[Mike Null]

Rich

If you use egg crate plastic be sure it is acrylic rather than styrene. Styrene melts and burns.

[Peter Odell]

Try Rubbing the back side with Dawn dish washing soap. Rub it all over the back and then you can burn and rinse off the dish washing soap

[Ross Moshinsky]

Pin tables are easy to make and more effective. Take a piece of 1/2" MDF and stick it in your laser. Have the laser mark a bunch of holes in a grid. Go back with your drill press and drill the holes the diameter of your pin (McMaster has all different pins available for cheap). A couple hours later you should have a nice pin table.

You don't have to use MDF but MDF is cheap and shouldn't catch on fire too easily.

[Mark Ross]

We cut acrylic every day a minimum of 8-10 hours a day 5-6 days a week on 2 Epilogs. When we get flashing it is always one of two things. A dirty vector grid or too much power.

[Miriam Ng]

Thanks everyone! Pin table it is! What does everyone think about Peter Odell's idea about using dish soap on the back. Is it safe? I'm try that too if you guys recommend it. Also what's the best solution to use to clean the laser grill? alcohol?

[Miriam Ng]

Thanks, Gary, I'll be making a pin table. Do you think home depot will sell anodized black nails? Where can I get transfer tape and what's it made of? Can I buy it from Home Depot? Thanks for all your help. I hope to pay it forward with my growing experience. Cheers.

[Gary Hair]

What does everyone think about Peter Odell's idea about using dish soap on the back. Is it safe? I'm try that too if you guys recommend it.

almost 8 years of lasering acrylic and I have never had a problem when I leave on the protective paper/plastic and used an aluminum grid. I think it would be a waste of time.

[Mike Null]

I'm with Gary after 15 years of cutting acrylic.