Sunday, September 3, 2017

A Trio of Shop Improvements

As a side project, I've been working on a few improvements to the G0704 mill to improve usability and fix some deficiencies in the mill itself. 

The deficiencies were minor - chip guards to keep metal chips off of the ball screws and sliding surfaces.  It came with one between the back of the cross slide and the Z-column, but somewhere along the line that has been damaged (obviously, I must have done it, but I don't remember when); on the other hand, it never had one in the front, between the cross slide and where the handwheel used to be.  It never needed one, except for the fact that I cut away an inch or so of base on Hoss' recommendations (top picture here), and the ballscrew would get exposed when the slide was moving toward the Z-column. 

I ordered a sheet of 1/16" neoprene from an eBay vendor, cut it to size and replaced the back piece.  Then I cut a second and made a skirt for the front.  This required cutting a little piece of 1/8" thick aluminum to clamp the rubber to the front of the slide, drilling a couple of holes and making a cutout around the oil fixture, but it was an easy job. 
The rubber sheet in the back (on the right here) had split in the bottom of the trough on the right, and also split on the left where it was attaching to the cross slide.  While it wasn't gaping open, chips could get in through the openings and onto the ballscrews.  The hole in the front was a different story.  When the table was all the way to the back, there was a hole there with well over an inch of the ballscrew exposed.  You can see it in the video here.  Chips, dripping coolant, small families of illegal aliens; anything could get in there.  In one of my GB-22 posts I showed a zip loc bag taped to the fixture so that it covered the opening when the table was forward. 

This needs a little work because the sheet on the front pulls toward the column with no problems, but when the table pushes back, it doesn't get out of the way.  I need to figure out something to do about  that.  Maybe it just needs to be a rigid piece of plastic and not a long floppy piece like that sheet rubber? 

The other improvement was to add a pendant.   Sort of.  A pendant is an interface to your CNC controller program, Mach3 in my case, that is portable.  You can bring the pendant to the mill so that you can jog the position of the slide when you're working on the table or something and can't reach the computer keyboard.  Commercial pendants can be complex and do lots of things, but at least for now, I'd be happy with a small box with six switches: left - right, forward - backward, and up - down.  Some years ago, I bought a Logitech Rumblepad 2 game controller, also for something other than gaming (to control a telescope) and while looking at ways to make a pendant, I remembered I still had it.  It took some reading online to recall how to set it up, but once the computer recognized it I was able to get Mach3 to pair with the Rumblepad and program some buttons to move X, Y and Z.  
While the commercial pendants tend to hook up via cables to the computer (USB or other serial port), this one is wireless.  That means it's easy to set it down on the table, so that when I've got my head and shoulders stuck in the enclosure trying to line up something critical, I can just hit a button to move the slide.  It also works from farther away, like across the room.  I just haven't come up with a reason why I'd need it to.


  1. Pretty slick, SiG!

    I always enjoy reading of your Adventures In Machining. Reminds me of when I used to do a lot of it.

  2. OMG that game controller mod is AWESOME!

  3. Ouch. I'm glad you don't have any employees. Still, way cheaper than buying their pendant. Glad to see the mill project still moving