Ahhhh, Pipe Dreams, we all have them! I just got back from one of my weekly twelve mile walks. I checked my computer for Emails. And just like a bad dream someone wrote me asking if the PCBMill could be made bigger. Not just a few inches bigger, they wanted feet! They want large size, Speed and accuracy! All for under two hundred dollars. I guess that is the price they expect to pay at COSCO or Home Depot. In their dreams!I answered the email and sat down for a nap! During this time I tried to figure out how to make a larger CNC machine that would be cheap, use parts found locally and be easy to build. While I was drifting off to dreamland the thought of using rollerskate wheels hit me. I put off my nap to look at some rollerskate sites on the net. There I found I could buy replacement wheels or bearings. Hmmmm, I wonder what Kmart has? At first it seemed crazy! I checked Kmart and Sports Arthority's websites. There they where, replacement wheels or bearings. The next day I walked six miles over and six miles back, returning with a package of sixteen replacement roller blade bearings. ($18)
The bearings come in different speeds. Beginner Type "3" or faster. They are made in China. A 5/16" bolt or stud can be used to hold them in place. They is a little play between the bearing and the 5/16" bolt, but this can be removed by loading the bearing towards the pipe. Now all I needed was a track for the bearing to ride on. Laughing to myself I ran it on a piece of Gas pipe. The bearing road very smooth on the pipe. I then bite the bullet and had some Gas pipe cut at my friend's hardware store. I built a wooden trolley and mounted the bearings on it. When I saw how well the trolley road on the rails, I was off and rolling!
The machine will cut an area 15" by 25" with a 1.5" usable depth. The cutting speed is eight to twelve inches per minute or more based on what you are cutting. The depth of what you are cutting and with of the cutting tool. The Dremel and the machine can only handle 1/8" or smaller bits. This machine is has been designed to cut out wooden or plastic model parts. It should have an accuracy of 1/64" or better based on how well you set it up!
11/13/2001 Today I did some more cutting using a 1/8" four fluted bit. I cut a test piece of PINE at 8" per minute at a depth of 1/8". The machine is now functional. This machine if built correctly, will cut out model airplane parts, gaskets,cut letters in signs, mill plastic,wood and circuit boards. Just remember, this machine was designed for the hobbiest! It was designed to hold a Dremel or small router. The booklet "The Pipe Dream a Make-It-Yourself CNC for the Toymaker in us all!" is $35 with free shipping and handling to Canada Only! I only ship and sell to US and Canada. For best results this machine should not be built bigger. It has a 15" X 25" cutting area with a 1.5" Z axis range. Again $35 to US and Canada Only!