[kiwichris]

Hi-ho,

Per my question in the BOB thread, I'm retro-fitting my K6100 router with LinuxCNC to replace the DSP controller.

The DSP controller has become unreliable, and I've never been 100% happy with it's Gcode support, and I wanted MDI back...

I chose a C11 BOB from cnc4pc.com and was hoping it would be here by now but the gods of international airmail were not in my favour, and I really need to get some stuff cut.

So.. I've wired the parallel port directly into the stepper drivers (They are opto-isolated) using 5V from the USB port for the high side.

For home sensors and tool height sensor for the moment I'm using LED's across the proximity detectors and probe. It's not ideal, and far slower than working with inputs to the controller but at least I can made dust. :-)

Down side, no E-stop, and the wiring is a little bodgy.

The photo attached shows the DIN rail where the old controller sat and the dodgy wiring.

Parallel cable and USB comes in along the bottom, and the terminal strips to the left connect the +5V and step/dir signals to the stepper driver inputs. The terminal strips on the right connect the prox sensors, probe and VFD signals to some LED's and a temporary switch to fire up the VFD.

Bottom right is a 12V / 5V SMPS which is providing +12 for the prox sensors and will provide the 5V rail for the BOB when it arrives.

End result: [ame=http://www.youtube.com/watch?v=ya5qGdSXx-M]Testing LinuxCNC on K6100 - YouTube[/ame]

Per the video, the rapids are getting a shade over 5m/min which equates to 27khz or there abouts. (320 steps per mm) I tested it up to 7m/min and didn't detect any lost steps or massive jitter/lag (37khz).

Obviously this is temporary, the BOB will be here soon and can tidy up. I've fitted ferrules to all the cables that will be re-used and mapped out what is required for the BOB so it should just drop in and go. (Famous last words)

The only thing I'm not 100% clear on is how to set up the tool height macro to set the G54 offset. I've read a couple of how-tos and blog posts and there is a bunch of assumed knowledge which I'll have to read up on to make sense of.

Cheers, Chris H.

[kiwichris]

Hi-ho,

An update of sorts...

Ran the machine for about 5 or 6 hours yesterday and started to catch up on orders. (MDF profile cutting for craft shops and direct sales)

Initially it was running _really_ slow cutting complex curve shapes, and found that G64 has changed since the EMC days. Using G64 P0.02 (in G21/mm) solved that.

Then I had an issue with the Y axis sticking (buzzing, stepper stall). Was happening when I made a 45 degree rapid at 5m/min which it had not done the day before. This was happening when the vacuum and dust extraction was working. An extra 5kw of electrical noise was causing problems for my bodgy interface setup it seems.

After a bit of messing about I reduced the max velocity to 4.5m/min and put the acceleration down a wee bit and all was well. I'm assuming the BOB will fix this issue, although it's possible it's an issue with stepgen on this PC.. We'll wait and see.

Having now used it for real, I have no idea why I didn't change the machine to PC based control a year ago when I got it. Changeover between jobs and setup was far quicker than with the DSP controller, and just having the ability to have long filenames for the gcode files makes a huge difference.

Using the 'jog until the LED lights' method of homing and tool setting wasn't as bad as I thought it would be, although it'll be good to have those as inputs again.

Another minor productivity gain came from not having the Z overshoot the upper limit when rapid jogging up to 'top right' to clear the table. The DSP would quite often hit the hard limit and de-home itself (or whatever the equivalent jargon is for that controller.) I ran 20 jobs and only had to re adjust the offset for a changed tool. I checked homing a couple of times just in case the machine was loosing steps and nothing was apparent.

Onwards...

Cheers, Chris H.

[kiwichris]

Tada!

One C11 installed.

Motion, estop, home switches are 100% as wanted and probe works but have some funky issues with the gcode for that which I need to work through.

I'll think about that later. For now I need to fire up and cut some stuff to make sure testing equals reality. :-)

I had a bit of assistance for the re-wire, but I'm not sure it made thing go faster or slower. Most of his input was licking. My face, as he was taking advantage of me working down at his level.

[kiwichris]

Photos... The app on my phone left them off...

[kiwichris]

It runs mid2cnc.py music better now that it's on LinuxCNC..

Super Mario Bros. CNC Music :-) - YouTube

:-)

[kiwichris]

Updating progress incase anyone is following this. :-)

The machine is going well, and I've added a spindle ready / at speed input per this thread:

http://www.cnczone.com/forums/linuxc...lay_dwell.html

I've also just ordered some more proximity switches to add end-limit switches to the machine. In it's original config it only has home/limit switches at the home position and uses software to control end stops.

It'll be relatively trivia to add + value limits to X and Y, although Z might be a bit of a challenge mechanically.

Either way it will add to my confidence leaving it running unattended at times when I want to get other stuff done in the shop as it's cutting.

The last issue with the LinuxCNC side of things is the tool height / touch off sensor... I'll read through the other long thread end to end when I get a chance...

I've got it working, but all of the variations on the g-code I've tried cause one error or another, and it's not as smooth as the old controller tool height setting process.

Will update the thread with the code I come up with once that is sorted.

Cheers, Chris H.