Thought I would share a couple of test cuts this morning to see just what the JTech 7watt laser can handle. Please see the Photo's. 2 inch disks Baltic Birch plywood 1/8" and 1/4" Pretty impressed but doing a large project with the 1/4" ply would take some time. Very Clean cuts considering the high power I was putting into the 1/4" ply. Thank you for looking
Thanks for posting this. I was wondering if making a multipass with a laser will cause the kerf to get wider at the top but it looks like it doesn't in your picture.
I thought there would be some deformation also but other than the burnt edge it came out perfect. No change at all in the kerf. I am still experimenting but it seems that unless I use a 100% power setting and a slow speed I am getting good results for small items. I should add that the plywood I use is multi layer so that may play a part in it cutting cleanly. I will try it on some cheaper plywood and see what happens. If JTech could come up with a stronger laser that would be the ticket. Even just a few more watts. I am now testing it on 7.5mil mylar to see if I can cut some stencils for airbrushing. Thank you for the reply.
Ok so I ran a few tests trying to cut mylar with no real good results. It will cut through but you end up with a burnt edge. I tried placing a piece of black paper behind it to help with the focus but that did not improve it. I also tried the paper on top and while it cut a clean crisp line in the paper it still burnt the mylar underneath and did not cut all the away through. I have seen this done quite successfully on Co2 machines so I wonder if it has something to do with the focal beam being absorbed by the Mylar. I will have to do some more research on this. I know it’s possible. I just don’t know how to resolve it right now. Excuse my messy penmanship.
445nm absorbs well into organics, but not so much into plastics The power is only part of the equation, the frequency of the light is important too. CO2 lasers (10600um) absorb better into plastics than 445nm near UV. Only having a 445nm at hand, your best bet would be to avoid the Mylar, and go for some thin black plastic (i buy file seperators - you know those sheets with the holes punched on one side,tabs with alphabet on the other, that you can use in a ringbinder to sort documents) at a local stationary store in packs of 100, and they do have black. Really easy to cut stencils out of that material, whatever it may be. The pigments seem to help absorb more of the 445nm light (clear just passes through)
Ok that makes sense. I thought I could find a way to cheat but apparently not. I will use my Graphtec Cutter for the Mylar and get those dividers you mentioned. Thank you Peter appreciate it.
