I have a K40 laser that I’ve had since April and I have basically been using it every day. I really am enjoying this thing! I have upgraded the board to a Cohesion3D Laserboard. I am using a Harbor Freight air brush compressor pushing air into a LightObject air assist head. I also upgraded the mirrors a little to some better quality Si plated gold mirrors. I had a better water pump to use in a 5 gal bucket with a temp probe mounted on the output stream. I use ice packs to keep the water temp at 68F or lower while in use. Oh and I ripped out the stock bed and cut the exhuast inlet back to give me a max working area of 300mm x 230mm.
Lately I have been trying to perfect my greyscale engraving skills. I take a .JPG and run it through Photoshop. I change it to a 16 bit greyscale image and do all my other stuff to it to get it laser engravable.
I usually engrave my pictures at a slow 30mm/sec to get dark burns in my Baltic Birch 12in x 9in plywood without really digging into the wood too much. The MA’s usually hover around 4 to 5. I have an arduino uno connected to the meter to output power percentage to a little 2 color lcd display and that shows 6%. I am using 16 bit pictures so I run at 100% power in Lightburn to get the most shades of grey possible.
Now the purpose of this lengthy equipment rundown is to give a little background on my setup and to ask a question. What is the longest run in one shot without pause that you guys have done? I just printed out a picture that took up the whole 12x9 inch plywood and it took 546 minutes (9 hours) to print. That was the longest I have ever continually run this laser in one shot. Of course I had to change the ice packs out every hour and a half or so to keep the temps below 68F. Is this too long? Am I going to burn up the tube? I have never noticed any loss of power during to print but I wanted to get you guy’s opinions and find out if anyone has beaten my record!