Hi all.
Just joined and new to lasers, I have been looking at a number of sites with suggestions as far as power and speeds but not sure what I am doing wrong. I tried cutting 1/4" Luan and mdf but it doesn’t seem to cut through well. I tried slowing it down to 2mm and 70 % and it still didn’t cut through. Alot of the sites say I should only need 50% or less for cutting and engraving. Is there something I need to change or do I need different length lenses or something? Thanks for any assistance you can provide.
First off is to ensure you are properly aligned and focused. If the basic setup is not correct, you results won’t be up to par either. @bernd.dk points out the mirrors, ensure they are clean.
A ramp test will ensure you are at the proper focus distance.
70% power can mean lots of things, do you happen to have a ma meter in circuit?
I cut 4.55mm plywood at about 10mm/s at 60% on my 50 watt China Blue from OMTech. I’m running about 14ma if I remember correctly.
Actually it just arrived yesterday and I need to install it. I checked alignment and looks to be dead on with a very small pinpoint with pulse. Yesterday playing with setti gs I had to run 3 passes to cut 1/4" mdf and even that didn’t cut clean with entire pattern. But I think it was set too fast 20mm per sec at 70%. I plan on installing meter tomorrow after work to see what I am actually getting. Will let you know.
It’s also my “normal” approach but, I have observed several times that when I have found the appropriate speed and then try to reduce power to the tube that I could partially go a few percent below the selected, high starting value. It could be clearly seen at my last test with 21mm solid pine. My starting point was (my) max power of 18% and 10 mm / s. At 5 mm / s I could burn again, but the cut became significantly nicer by reducing the energy to 55% (14 mA)!
It is probably related to the actual light intensity which is different at different speeds.
My setting philosophy is as quickly as possible with the least necessary energy.
I’ve found when I cut natural products that the best speed/power leaves very little ‘soot’ or other burnt items. Sometimes it can be within a couple percentage points. As each wood, of the same type, does vary as it’s natural, especially between lots.
When I setup to determine cut, I have a paper towel to wipe over the cut and see how much residue is left.
Yea Jack so far hit and miss got the meter installed and at 2mm sec and 85% it is using about 7ma and cuts 1/4" Luan in one pass, but there are many areas that burned on the back. So I still have some tweaking to do. The focus is pretty much dead on with the plastic piece they sent me with the laser.
