Laserscript user forum

Hi guys, I have an issue with items being marked on the underside when being cut out.

It's where the laser exits the material and is obviously hitting the cross pieces of the bed frame.
On acrylic it makes a chip like mark on the edges. MDF you get a slight burn/discolouration.

My laser has had some use and the blacking of the bed is worn off. I wondered if it was the laser reflecting/refracting back off the bed frame due to the blacking being worn off?

Has anyone else had this problem?

I've also seen some honeycomb mats that are placed on the bed underneath your material when cutting.
Are these a rubber type mat? Has anyone got one? And if so, what do you call them!? I can't find one anywhere, they're just in images that I've seen on various sites.

Hi Rog,
HPC sell the honeycomb beds - they are metal and still suffer from reflection. I use magnets to raise the material off the bed about 5mm - it seems to be the best way apart from using a pin bed which I also have (but no longer available).

The black coating will help a little bit but space and just enough power is the best way as far as I can see

Best
Dave

Hi Rog,

Another couple of tips:

(1) Cut some perspex rectangles, about 20mm x 50mm, with a 3mm slot in the middle. Slot them together in pairs, and you have cross-shaped things which you can use to raise your workpiece off the bed. I use about 10 X's, and I seldom need to replace them. Obsessives make the upper edge of the rectangles have saw-teeth, to minimise the contact area.

(2) Obsessives might also suggest that you're using too much power. Ideally, you want to JUST cut through the material, so that if you had, say, a piece of paper under it, it wouldn't be cut through. Now that's practically unattainable, because it'd require loads of tweaks with every substance, and every day the laser power fluctuates, depending on the weather, the temperature, earth-ray-thought-forces or whatever. But the closer you can get to using only just the energy that you need, the less damage reflections will cause.

Hope this helps!

James

Hey James,

This is a good idea thanks! I was looking at making something like this. Will try these