2x2 workshop build

I got a 3d printer last January (2016). I had it for probably 2 months and came across the MPCNC. I’ve wanted a CNC router since probably 1998 or 99, but they were very expensive. The DIY ones almost always started with “First thing you do is take the CNC machine you already have and make these parts.”

This one does that, too, sort of, but the $300 duplicator i3 was much less of an initial investment. Plus, this time I actually did have the machine to make parts for the new machine.

Anyway, I printed out all the parts, ordered the hardware kit, and…it sat there for a while. I’ve got two little kids and a wife that works so time isn’t something I have a lot of.

One weekend back in May 2016 I put the frame together and put the rollers on the frame out in the workshop. Over the next week, I assembled the middle and the z-axis in the garage.

When I finally got back out to the workshop…the rollers had all split/separated/disintegrated with literally no load on them! I didn’t know it at the time but I had used very poor filament and printed them in my garage with 85-90% humidity. I reprinted the rollers but after inspecting the middle assembly I realized that needed to be re-done, too. So I put it on the back burner for a while.

Well, over the last year I’ve come a long way with my i3 and have gotten a lot better with it. I finally printed the new middle assembly and new z-axis. And this weekend my mother came over to watch the kids and I assembled everything.

IT’S ALIVE!!! What a great feeling to get all 3 axes moving in repetier. I still don’t have a tool mounted because I ran out of time, but I’m printing a pen mount tonight to get started.

SO NOW THE BIG QUESTION:

Now what?
I see people have driiled holes in their bed for holding the work, is there a “standard” grid I should use for that?
I have a D660 that I plan on using for cutting, with dreams of a dual extruder and laser engraver (with 4th axis, yo!)

Looks good! Make some dust.

The only requirements for the holes in the bed are:

  1. They fit your clamps and
  2. The clamps can reach the workpiece.

I use the cheap F-style clamps from harbor freight: http://www.harborfreight.com/6-in-quick-release-bar-clamp-62239.html

I used a dremel to grind off the nub on the bottom, so the clamp part can come off, and I can put the top part through the table. IIRC, I needed a 7/8" hole. I only made 2 holes, and I put a screw in the far edge of the workpiece. That works OK. You can also put a screw through another stick/board, and use it as a clamp, with one end down on the table, and one on the workpiece, with screw in the middle.

If I was going to use only the clamps, I would make holes about 4" apart (the clamps have 2.5" “reach”) along the front and left side, and then along a diagonal across the middle. I would put the left and front ones outside of the reach of the tool (not that it matters that much, but it will keep the full work area for large pieces), and then I could always mount the piece starting at the front left, and put a clamp on every corner.

I’ve just been using screws more often though. My spoil board is getting spoiled faster than I thought, so I’m not too attached that I can’t drill some holes in it. For the last project, I even make a special gcode file to drill holes in areas where I wanted to have screws at the end, and just clamped one edge of the workpiece down, ran the gcode for the drilled holes, and then countersunk, and buried some screws, all without changing the location of the workpiece, or the 0,0,0 location of the machine. Then I removed the clamps, and did the cutting, and that worked great. Just make sure you account for the size of the screw and the amount of surrounding material you’re going to waste when you choose the location of the holes.

Another thing that would be neat, but I haven’t quite figured out how to do, is to be able to clamp a board so the router can work on it’s endgrain. I’d need a slot that was perfectly aligned with either x or y, and then a surface underneath that I could clamp the workpiece to, at a 90 degree to the table, along the exact X or Y axis. That would be great for making neat joinery for a drawer front or something.

Same thing as Jeff, I use screws directly too.

I suggest you do this at least at the beginning, while you try to learn how to use the machine, since you’ll destroy your spoild board much more than when you’ll be very experienced.

Just take very good care not to hit the screws with your bits during a job.

Nice machine and congratulations for your build by the way !

I went with a piece of T channel down each side of the spoil board, it didn’t interfere with my workspace at all and I can use clamps like these to hold the piece. When the edge of my piece is too far from the T channel, I just add a piece of angle iron to bridge from the clamp. My spoil board is screwed in place in the four corners, outside the workspace, and then milled flat a bit larger than the work area (3/4" surfacing bit with carve setting on the perimeter gives me 3/8" extra all the way around).

Excellent advice. Thank you, gentlemen