Desktop CNC

I read with interest the review you did of the desktop CNC system in the last issue of MAN. I am intrigued. Can you tell me the advantages of a hobby-grade CNC versus a laser cutter? Thanks for the great technical articles—keep it up.— Scott Michaels, Boulder, CO

Scott, thanks for writing. I had a lot of fun assembling and learning how to operate the desktop CNC system from Stepcraft. I’ve run several test jobs with it, and you can see them online at ModelAirplaneNews.com/stepcraft. First off, as with any relatively expensive piece of shop equipment, you first have to define what you actually want to accomplish. If you simply want to build some models, I would not recommend spending the money if, in the end, you could do the same tasks with a band saw. If, however, you are interested in producing multiple precision parts, then the investment is valid. Having both a 40-watt hobby laser cutter and the CNC, I’ve learned that both are useful and each has its own advantages. For thin wood stock, like balsa and light plywood (up to 1/4 inch thick), the laser cutter can produce a lot of parts quickly. To cut thicker wood, you need to invest in a more powerful laser cutter in the 90- to 100-watt range. Also, it is great for engraving wood and cast-acrylic awards and plaques. If you want to do more and produce much thicker parts—like 1/2-inch-thick firewalls, 1/4-inch plywood formers, 1/8-inch plywood wing ribs, and other load bearing parts—then a three-axis CNC is the way to go. Plus, if you want to cut and machine other materials like carbon fiber, aluminum, and brass sheet materials, then the CNC wins hands down. My hobby laser won’t even dent these materials.—