Enlarging Laser cutter work-area ?
I have the 20 x 30cm 40W typical cheap Chinese job waiting at home for me ... and I wonder if it's possible to enlarge cutting area ... Even if the stepper rail is kept same length, is it possible to mount so an open-ended bed is under where a piece to cut can be fed in stages - so cutting a much larger item than the closed box ?
Can the cutter be fitted to longer rail and bigger box ?
My machine will be fine for formers, ribs etc. - but fuselage sides, wing spars will not be possible unless I can extend ...
Any advice / info would be much appreciated ................
Yes and no... There is a home-built cutter based on the "Roto-Zip", "Dremel" or similar rotary cutting tool which uses the system you describe. It can have a virtually unlimited length stock fed in.
But altering an existing laser cutter might be more trouble than it worth.
I'd look at ways around the stock size limitation of the machine first.
Fuselage sides can be parted together for length without much issue as you just run a square stock longeron or other reinforcement to bridge the splices. (sometimes without even that, just a good glue joint)
Spars also tend to be based on strip stock if doing a wood frame build. You could have sections of shear web material between the strips that are laser cut to space the ribs.
I have been thinking of doing this to my laser cutter. You have really three choices.
1. Make a larger machine cutting area. I have put some thought into this I would get an old freezer as square as you can find. Lay it down so the door opens in the up direction. Everything on the K40 is all belt driven. It shouldn't be that hard to simply make new linear slides that are much longer and since you are not pushing a router through the wood the nema 17 steeper motors should still do the job nicely. The freezer should be large enough to house everything out of the K40. The hardest part will be extending the wires, this will require Mach3 and the new board from chriscircuts.com its a plug and play
board designed for the K40.
2 Another option would be to cut slots in your laser housing and make registation guides and cut in more then one step. So say take a 36 inch piece of balsa and move it over say 10 inches and cut it in 4 steps moving it exactly 10 inches every time.
3. The way I have chosen so far is to make a MDF template the old fashend way and then use a trim router with a fomica flush bit be sure to get the one with the bearing guide. Now just follow the template and you should get an exact copy. You end up trimming the corners so they are square but it does work.
I have not built or used a laser cutter. That being said, I do understand how they function.
I have considered a few options for long kit burning, and the best idea I have would be to make the X axis operate a sliding table, under a bridge that the Y axis operates on. I have seen a router CNC system that operates this way. My friend can make things 10" wide and 48" long or more.
My thoughts were that the X axis stepper motor, would rotate a pinch roller system, that would move the slide table left or right. It would be easy to make a slide table that would be very stable in movement one direction, but not allowed to move in the other direction at all. Maybe it could be just a sacrifice table of MDF, replaced when it is too burned to use.
I figure this way of doing it would make a smaller sized machine when not in use, but allow a slide table to be inserted through openings in the ends of the cabinet. The openings would allow fresh air to enter to sweep the burning smoke up through the exhaust fan.
If I am totally misunderstanding something, please let me know.