Wednesday, April 27, 2016

Still Making Chips

I'm still cutting aluminum for the CNC conversion project, I just don't have any finished pieces to show off.  Not since the weekend.  I've just been rough cutting and rough shaping all the pieces to minimize the cutting time on the small CNC mill.  Here's all the stock. 
The two pieces of angle aluminum on the right are the X and Y motor standoffs, cut to final size but not drilled and tapped.  That shouldn't take long.  The two pieces on the left that are kinda pentagons (but really squares with one corner triangle cut off) are the motor mounts these will mount to.  They're the right overall size but need all the holes drilled and bored.  In front of those is a rectangular piece with a lot milled away - you can see one end has an edge that's about half an inch wide and standing not quite a half inch above the rest of it: that's the Y-axis ballnut mount.  It's a little oversized and ready to drill and bore its holes, then thinned to final size.  The little piece to it's left is the X-axis ballnut mount I showed on Friday.  The two scrap triangles are behind that.

Behind all those pieces are the Z-axis ballnut mount and Y axis spacer (thicker chunk) standing vertically on top of the X-axis endplate.  None of those are rough shaped at all, other than being cut from longer pieces of bar stock. 

Not shown are the couple of cubic inches of aluminum chips and sawdust I've put in the Shop Vac.  All of the rough shaping has been done on the big mill because it can take such big cuts compared to my CNC mill.  I have a carbide square facing end mill like this one that's simply awesome to use, coming from my light duty Sherline hybrid.  I can take a 1/16" deep cut across the entire top of a 1 3/8" wide, 2.3" long aluminum chunk and it doesn't even sound like it's working.

By the way, I puzzled for a long time over how to take off the triangle on those (pentagonal) motor mounts.  I don't have any 45 degree blocks to set up the cut.  On the other hand, I have some V blocks with a 90 degree included angle (like these) and I realized I could set up the V block so that the edges are parallel to X and Y on the mill table.  That made the geometry perfect for a straight cut to remove the unwanted piece.  The corner of the square fit tight in the 90 degree V, leaving the piece to be cut off just hanging out there.  Simple straight cut on the Y axis (away from the camera toward the accordion-pleat Z-axis screw cover in the distance).  
As I've said before, I'm not a real machinist.  I don't already know how to pick up a print and do all this, I'm just trying to learn to make stuff.  At this point, every piece is a puzzle and I'm learning more doing this than I thought I would.  And every so often I get some cut or finish looking really good and when I think of being able to do this, I channel my inner flounder


  1. I've often thought it would be a neat thing to use CNC for milling wood into things like cases for cell phones or the housings for TV remotes.
    I don't have time to pursue the idea myself but if I had a Motorola TV remote encased in wood I think that would be pretty cool.

  2. The parts look great, you figured out the setup for the angle cuts and you made progress. Wins all the way.
    Will any pieces be round, and visible, and thus a candidate for knurling?

    1. Hmmm. Round, no. Visible, yes. I think some of these are going to get powder coated. I like the idea of anodizing, but I'm not ready to cross that bridge.

    2. Just stumbled across this, SiG, and thought you might get a kick out of it:
      (CNC machining of a pencil)