In the fall of 1996, I started getting interesting in marquetry, just as reason to build a CNC router. In February 1997 I started Inlay.com, with the hopes of learning more about marquetry, inlay, and mosaics in general. I built a homemade CNC router, it was neat, but its performance was lack luster. I almost took a job that involved programming a CNC waterjet, but that fell though; I was a bit greedy on my salary, live and learn! All along, people were telling me from time to time, to check out lasers to see how they can be used in the craft, but I just never looked into it.
In summer of 2000, I started work at a company that had a 50-watt laser engraving, cutting machine. In all honesty, the laser was one of the biggest job benefits. I actually started at the company, without seeing it first. Now I have to fill you in a little, I have been in many shops that have industrial lasers. The large industrial lasers are like 3000 watts, and can cut one inch (2.5CM) thick stainless steel. They have the ability to turn a full 1/2" (1.3CM) sheet of plywood into shreds, in minutes. This laser just does not have the gusto to pull a stunt like that off.
So this was part of my job, to program this machine, that I had never seen. I knew the company used it to cut out, and engrave plastic panels, and thick paper, but I still had the idea in my head of a truck-sized machine. This machine is about the size of a standup copier. The first time I seen it I was rather disappointed. That only lasted a few minutes. I was awed and memorized by the way it cut! It was a useful machine after all. With a CNC router, one has to hold down the material so it doesn't move while cutting. In a laser cutting machine if you follow a few simple rules, no hold-downs are required. You do have to worry about pieces moving after they are cut a little, but still this is much, much easier, then a rotary machine.
How it works is quite simple. In the back of the machine, there is a 50-watt CO2 laser tube. There are mirrors and lenses, which get the laser beam, to the yellow lens at point 1 in the picture below. At point 2 there is a right angle mirror, that redirects the beam to point 3. At point 3, there is another right angle mirror that points the beam downward. Along with the mirror, there is a lens that focuses the beam to point 4. The lens that I used had a two-inch focusing distance. You can see there are 3 screws at point 3; the right angle mirror, and lens assembly comes out for cleaning. I don't know why, but I was surprised that the laser beam was not enclosed in its travels. You can see from the top picture on this page, that the user is protected from the working compartment, by the top lid of the machine. The window is coated to protect the user's eyes from stray laser light.
The beam is moved around by 2 slides. The Y slide is the beam that is between point 2 and point Y. It travels on rollers at points 2 and Y. You can see these rollers at point Y. So this bar travels back and forth, from the front of the machine to the back. Gezz this sounds so dry and technical! Anyway, the lens assembly, or laser head, at point 3, is the X-axis. It travels from left to right, on rollers at point X. These two slides are move with cogged belts, which are moved with stepper motors.
The bed of the machine travels up and down on four lead screws. One of them can be seen at point Z. These four lead screws are powered by cogged belts that are all powered by one stepper motor. The reason the table moves up and down is so you can focus materials of different thicknesses. The bed of the machine will go down 8 inches, in case you had something 8 inches thick to be cut or engraved. This comes in handy if you wanted to engrave a trophy, or the back of your boom box.
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