CNC bridge mill for cutting aluminum.
Here's a project I've been accumulating parts for & finally got started on this past weekend. It's router/mill meant to cut up to 3/4" aluminum plate with a +/- .002” tolerance & drill/tap up to about 10mm holes.
It started when a really great guy on over on HMEM made me a deal I couldn’t refuse on 3 industrial linear slide units with ballscrews. I started doodling in TurboCAD to best utilize them improving an old router I built a long time ago. One thing led to another & the decision was made to build a new machine utilizing a heavy duty table I stumbled onto on ebay.
It’s aptly called a “Brute” machine base made by the American Grinding & Machine Co. in Chicago. I got this one for $315 which I think is a steal. It came with 1 large electrical box and a smaller one on the other end. When I opened the boxes I found a bunch of DIN rails, cable tracks, wiring, a 3A 24vdc power supply, a 30A contactor, a bunch of 12ga stranded wire, DIN mount fuse holders and a ton of DIN mount terminal strips. It was way more than I bargained for.
That’s just the icing on the cake though. It’s an all-welded design made with 3” square, ¼” wall tubing with blanchard-ground ¾” steel top & feet. I feel pretty sure it’s stress-relieved before the grinding is done and the fit & finish quality is great. The specs say +/- .001” over the entire 24” square top & it checks out with an accurate straight-edge. It weighs over 440 lbs incl the electrical boxes. What better foundation for a solid CNC machine! I don’t know if I should call it a heavy-duty CNC router or a medium duty CNC bridge mill….I’m thinking the latter until proven otherwise.
Here’s the stuff I have been accumulating for the project. 6 - THK linear slides, 3 - 425 oz/in stepper motors & 4amp drives, 36v switching power supply (probably build my own 48v linear supply later especially if I build up a 4th axis) a dual parallel port card to go in the Dell XP PC I fixed up for it, an LMS Sieg X-2 mill head/R-8 spindle to be powered by my trusty treadmill motor & KB speed control. The grey posts in the background will be used as part of the fixed y-axis bridge. They’re 3” square ¼” wall tubing with welded 3/8” flanges on one end. I’m still working on the bridge design and my plan is for the whole thing to be bolted & doweled together so I won’t have to deal with welding/stress-relieving/issues. Approx travels are 20" x 24" x 10". Blinding speed is not my goal with this machine; just clean, accurate cuts at whatever speed & I'll be happy.
I’m sure I’ll hear complaints about the mach3 P/Port control & that it should have servos instead of steppers but at the sad state my hobby-budget is in, it’s all I can afford!
I'm posting here & a couple other forums I call home as well so my online friends can give me a swift kick when necessary to keep me motivated.(nuts)
Milton in Tennessee ya'll!