Last month I took the MultiCAM training class at Artisan’s Asylum. As mentioned previously, the MultiCAM is a large CNC gantry router capable of rapidly machining plastic, wood, or aluminum sheets.

One relatively advanced feature that it has is the automatic tool changer which allows the use of up to 8 different tools such as drill bits or endmills. Another is the vacuum holddown system which eliminates the need to clamping or screw the workpiece to the table. Because of its speed and versatility, the MultiCAM is capable of doing a lot more than our other CNC router, the Blackfoot. While I was taking the class it was announced that the Blackfoot will soon be replaced with a ShopBot which is more evenly matched to the MultiCAM in its capabilties.

Doug Ruuska, the guardian of the MultiCAM, taught this class. The machine used to be owned by a company that he worked for, and he ran the machine there. When the company decided to get rid of it, him and a few others got together to buy it and lease it to the Asylum. So he has quite a bit of experience with running it as it was used for production runs of aluminum components machined out of ½” plate. The types of projects it’s used for at the Asylum generally don’t come close to that kind of use. The class and the fee for running the machine help to pay for the lease as well as putting money into a fund for maintenance. One of the disadvantages of a high-end industrial machine is that the components aren’t cheap.

Collet parts

Assembled Collet

The class consisted of four sessions. In the first, we spent time going ove the setup of the machine, which consists of turning it on, setting global and local home locations, setting the height of the material, putting the tools in the tool changer, and setting the height of the tools. The MultiCAM uses a cool system for setting tool height – The tool is gradually lowered down onto a metal block which, when it touches the tip of the tool, closes a circuit which lets the machine know that it has reached the correct height. On the Blackfoot, this has to be done manually, for example lowering the tool onto a strip of paper until it just traps the strip.

MultiCAM Cutting

Chair made on the MultiCAM

In the second class, we went through the process of cutting an example part. We each made a chair out of ¾” plywood. In the two classes after that we had the option of bringing our own projects, but no one had anything ready, so we helped Doug machine parts for a new Burning Man sculpture that he’s working on. The machine was cutting ½” plywood at 150 inches per minute which is pretty fast. Still, having to monitor the machine while it does a whole run of parts can get tedious. Each sheet took about 20 minutes to complete. But the process gave us some practice and helped to cement the steps required to set everything up. Doug encouraged us to do a project using the machine sooner rather than later so that we don’t forget.

Cutting flat parts

Cutting 3D contours