Grizzly G0704 Cnc Conversion

It has been a couple of weeks since my last post, so just a little update. I'm rearranging the shop and getting the pieces in place to start taking the Grizzly apart. The big change is in this view of my shop a couple of days ago.
NewShopLayout.JPG
You can see the mill is on a rolling base, the one Grizzly sells for it. You'll note the new wood chip tray is over against the left wall. While I was figuring out how to lift the 350lb lathe and base cabinets with the shop crane (visible at the left), my wife got behind it and found she could push it on the smooth floor. My wife is rather petite: 4'10" and a small fraction of the weight of the lathe on its stand. Between the two of us we pretty effortlessly rotated the lathe 90 degrees to the direction it was in, and slid it toward the right - toward the camera in this view. Guess that means I don't really need the mobile stand I bought for the lathe but hadn't put together.

My big remaining jobs are:
  • Fix/build/buy a computer to control this CNC mill. I'm almost definitely switching over to LinuxCNC for this from Mach3, which says the computer will be Linux instead of another XP box like I have. (I use Mach3 to run my Sherline CNC mill and lathe). Because of past Linux experiences, this is a scary step to me. I've run Linux a few times before, and it always seems if you want a computer to just do common tasks, it's great, but if you need anything unusual it can be a total disaster. Unusual things like a Linux driver for a USB-connected motion control board. The computer needs to be a priority now, because I'm going to need the CNC controller to control the next part:
  • Build the box to hold the hardware for motion control. I think I have all this hardware, mainly the stepper motors and their controllers from Automation Technologies. I have an emergency stop switch, limit switches, connectors for cables, and all those niceties. The limit switches get built into the next part:
  • The CNC conversion to the mill. I'll need to take the mill apart to the subassembly level for this - maybe not to individual pieces of hardware. I'll need to modify the base of the machine with a drill and angle grinder. This is where the adventure really starts, because if I did something wrong and need the mill to fix it, I'm SOL.
  • While the system is apart, I need to add the oiling system, which will pump light oil onto the leadscrews and a few other places. I have the oil fittings, but not everything, just most.
  • When the system is back together and cutting metal, that's the time to build the enclosure and cooling fluid system. I have most of those parts, too.
Whew. I wonder if I can get it done before my one year anniversary of retirement in December?
 
The best laid plans of mice and men...

I did complete the first two items on that list in my last post. I got LinuxCNC running on the designated computer. I got my motors running in a temporary setup. It's just that between the two computers, neither one is really good. They both have odd intermittent problems. The Linux machine won't start most of the time, and has to be turned off and on to get it to stay on. When I eventually get it running, it seems to stay running. The Windows/Mach3 machine will start and run, but then freezes sometimes when I move the mouse. Maybe once every couple of months. It has never hung up while running CNC, so that's a good thing. I can't tell if the system would halt or keep driving until the system hits the limits, breaks tools, ruins work pieces, all that.

Right now, I'm planning to use the Mach3 machine with two configuration files: one for the old Sherline systems, one for the new Grizzly. Meanwhile, I'm trying to make sure everything will fit in the box I've got dedicated for it by modeling it in Rhino, my 3D modeling program. The model includes a fourth motor controller that I don't have, for an eventual rotary table.
ControllerBox4.jpg

Still plugging along.
 
Since it has been about three weeks since the last one, time for an update.

The last picture showed my model, at that time, of the test box. Things continued to move around in the box and on the rear panel, and other things needed to be ordered and received. The latest model, which I'm calling the "final version" (hah!) is this:
Box_Final_Model.jpg
Sharp-eyed readers will notice that the breakout board has moved toward the viewer and the chassis is now cutout with a sloppy tolerance opening for the DB-25 hard mounted on the BoB. I simply didn't have a simple, clean way of connecting it where it was. The fan is obvious, but in the lower left is a new part I found. This combines all of the AC input parts into one much smaller part: the AC socket, the power switch, a fuse holder and an EMI filter, all of which were separate parts in the previous version. The four DB-9 connectors move from that group of four on the right into a single row across the top of the rear panel.

Once I had everything located, it was time to locate all the holes. The bottom was the simplest piece, so the first one I attacked. This is the bottom panel put into the rest of the chassis as a test to make sure everything fits as intended. It all did.
ChassisMockup.JPG
Once the bottom was drilled out and tapped in the right places, it was time to go over to the back panel. It has four DB-9 connectors on the top. I had a file I found online somewhere that would cut them, but ran into some problems with it cutting too big. I ended up writing my own file to cut them, but wasted a few days getting through that. After two test cuts, I was ready to move over to the real thing.
BackPanel.jpg
That's my progress as of Monday. I have two rectangular cutouts to make, and then drill out the fan holes; right now I'm planning to change from the 1/4" holes over to a #5 center drill, so that I can potentially cut and debur in one step.

I wasn't sure it could, but thankfully my A2ZCNC/Sherline mill can handle the entire 16 x 6 1/2 panel to cut some of these features. Especially if I do a little at a time.

Still plugging along. I always do my best to answer questions, but I'm in the highest danger zone for Hurricane Matthew. I expect to be without power for a while over the next few (???) days.
 
Time for another update. All of the metal for the test box has been completed and I've started wiring things up for good. The back panel required three separate setups, which is painful, but it's actually larger than my Sherline/A2ZCNC hybrid can handle. The array of holes is for the fan; the two rectangular cutouts are for the Breakout Board (the longer, narrower one on the left) and the AC Interface (Corcom line filter/switch/fuse/AC receptacle). The panel is upside down in this view; the row of DB-9 cutouts goes at the top. The BoB is on a mount: a piece of 4x6 alumimum sheet, 1/8" thick. It has six holes in it, but I did it on the mill as a precision drill press. It screws to a small piece of 3/8 aluminum that's tapped 6-32 in four places: two to mount to bottom plate and two to mount to the 4x6x1/8" sheet.

DrilledPanel.JPG

Several test fits were checked. I had to make a minor correction to the BoB mounting bracket, moving it back about 1/8" from the rear panel. I laid it out by hand and messed up.
TestFit1.JPG
Note the BoB isn't really mounted, just hanging there on some screws.
TestFit2.JPG
This a test fit of the Corcom part.
Finally, an inside view of everything.
TestFit3.JPG
Again, the BoB and mount, the fan, and the AC input aren't mounted "for real". No hardware.

The last piece to machine was the front panel, which gets a mess of holes (for air flow) and a large hole (7/8") for the Big Red Stop Right F***in' Now switch.
FrontPanel.JPG

Like I say, I've only just started wiring, so it will take a couple of days to hook everything up, since I'm trying to be neat. I had the demo setup on my benchtop in an hour or so, but I had no cares about making it look nice. Hopefully, within a week, I'll be able to post a video of the computer running motors on the benchtop.
 
You know I looked at that back panel for two days before I realized, "hey!... that switch is in the wrong corner!" It was supposed to be in the upper left corner. See, I'm used to looking at it from behind, from the inside looking forward (see the models a few posts farther up). It's in the upper right viewed from behind.

That said, it's not a problem: everything fits, and the switch works. It's just not the way I drew it in CAD, so it's a personal pride thing. The box is wired now. I don't have the cables to connect it to the motors made yet, though.
 
Switch on the left or the right, it still looks Fantastic. Great work.
 
It works! Got the box finished, completely wired. Made all the cables and interconnects. Plugged in the three motors and everything works on command.

This is the box on my messy bench when I finished it.
TestBoxBench.JPG
A closer look inside
TestBoxBuilt.JPG
It's all ready for adding a fourth axis. I don't have a rotary table, yet, but I went ahead and ordered another motor and controller so I can add that some day and all the hardware will be compatible.

Here's a video of the motors turning for a few seconds. Left to right: X, Y, Z. The very end of the video shows me pushing the Big Red Stop Right F***in' Now button, then showing the motors not moving, and finally doing a clumsy camera pan over to the computer to show Mach3 responding with "Hey, you told me to stop".

After a little minor cleanup, it's time to take the Grizzly apart and start doing the actual CNC conversion.
 
great work! It's always very rewarding when things work the first time.
 
Just a photo of the controller box with the cover I made for it. It came with a black sheet steel cover like the bottom cover most everything is mounted to, but my wife remembered a piece of plexiglass she has been moving around the house since the early 80s. She thought it would be a good top for the box, since there are diagnostic LEDs inside and a see-through cover would make it easy to check those lights if something starts going wrong. Seemed like a good, practical idea to me. Finished, it looks like this:
ControlBoxCovered.JPG
Yeah, it was orange plexiglass. I'm sure I'm the only one on the block who has one. Or the only one in the world. For some reason, I decided to use the junk screws from my powder coating adventures I talked about, so those are blue. Gives it kind of a wild color scheme.

The really observant will notice there are four motor controllers in here, while the picture a week ago had three. The fourth axis is installed and tested. I don't have a motor just yet, but that's OK. I don't have anything for the motor to connect to!

Does anyone know of a good rotary table for a mill the size of a G0704?
 
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