Hello, i am absolute new to laser-engraving/cutting and i have a few questions.
I ordered a Trocen-controlled 50W CO2 laser from ebay.
The “bed/table” (as we call it in the 3d printing community) is made of shiny metal, still covered with blue protective foil. I am worried about the laser reflection, potentially damaging my work’s backside. Should i place something else as a bed? 3mm wood?
After a few trys i have the strange feeling that the bed is not “leveled”. If i engrave a circle, one side is deeper cut as the other. Is this a common problem, or within an acceptable range and normal and if not - what can i do about it?
The aircompressor is really loud on this machine. It is a cylindrical device somehow bolted to the chassis. I thiniking about isolating it with ruber or something else. Any ideas?
First mod to do: adding an ampmeter. I didn’t manage to cut 3mm transparent acrylic with settings like:
Speed 15mm/s, Power max 40%, passes 10 (!)
So, at the moment i am guesstimateing 
Thank you!