EMC2, CNC, Old Computers, and Stepper Motors

 
 
 

I decided that I would go ahead and install Ubuntu and EMC2 on the junker dell 900 mhz computer. I had tested the system with theUbuntu 8.04 live cd. The live cd ran pretty well and the latency test was good too (a test where you run the terminal to get the command line and run the command , it measures how well the computer will do as a stepper motor controller).

I did the install and started in on trying to run the xylotex controller and it didn't work. I figured out that I needed to run stepper configuration wizard. I figured out (I don't know linux very well or emc2 but am learning) that many of the features of emc2 are accessed by the linux command line which is accessed by the terminal application. As it turned out I didn't actually have to run it from terminal, it was also in the EMC2 run programs tab.

So far emc2 is pretty nice, not that I have much to compare it to. The stepper config had presets for the xylotex controller which was pretty nice, but if it had not been there it would not have been too bad to set up. There was a "test" button that allows you to run the axis to test the speeds and acceleration which really simplified finding the max speed to run the steppers, one thing though it defaults to a 15" sweep which would crash my sherline as it does not have 15" of travel. Just have to be careful, which is generally good advice around semi autonomous machines. I discovered that it was traveling .5" on the sherline axis when the settings on the stepper config were indicating 1". After going over the controller settings in stepper config I went to the xylotex documentation and discovered that there were jumpers (I never really understood this before) for microstepping. The xylotex board was set for 1/8 micro step and EMC2 was set for 1/2 stepping. I found a fairly decent explanation of stepper motors in a microchip applications pdf.

End of day I had the lathe minimally running on EMC2. All this was something of a boondoggle on my part. I have been putting off cutting chips. Partly the mess and partly that I have to finish shrink tubing the wiring. Another thing is that I am running turbocnc. I think it is okay but I have some problems copying g code, I have to use floppies and they are becoming a problem with the computers I have (the computers use win 98 and dos. At least with emc2 I can use a usb thumbdrive to transfer files, and there is a chance I can get wireless to work.

Another nice thing about EMC2 is that the GUI has a graphic view of what the gcode is doing. I am going to use it to help learn g code.

I might try mach 3 also, first I have to put the computer I set up back together.


Link on Stepper Motors and Drivers for CNC at otocoup.com

Helpful link on Make: CNC Buyers Guide