[Vulcan R&D]

I have been cutting MDF and melamine faced MDF (6mm) for some time on my chinese laser. I have never had a problem cutting the single sided melamine faced or the double sided melamine faced. Recently I have had to slow down on my speed in order to cut through in a single pass. That really isn't the major problem though as my tube is probably due for a replacement as it is about a year old. The problem is that I can after slowing it down cut through the single sided 6mm melamine faced MDF just fine but no matter what settings, high power/low power, high speed/low speed I cannot get it to cut through the double sided melamine faced MDF. It almost cuts through to where I can see the cut on the back side of the piece but it never quite cuts through no matter how many passes etc. Also it chars VERY badly even at like 30% power. Nothing has changed conifguration wise. Acrylic and other materials cut normally.

Thanks!

[ozstockman]

my guess it is either your optic dirty(lens, mirrors) or you have dirt stuck to an output coupler of the tube itself.

[fishface]

I had a similar problem with plywood. I eventually traced the problem to be dirty optics, but not the lens or mirrors - inside the end of the laser tube itself! Smoke from the ply was escaping into the section of the machine that holds the tube and had formed a dirty film on the tube (unimportant), but also on the end where the light comes out (very important). I couldn't clean it properly without removing the tube, but when I did it was easy to get a cotton bug (q tip) into the end with some isopropol alcohol. To my surprise, i was able to put it back in without having to re-allign the optics again.