PM-940m CNC - VS Motion Controller Conversion to Centroid Acorn

That's very interesting. I had a similar issue when I first started running the Acron and it was very frustrating, I chased it back to a miss wired +24vdc on the input strip. I missed it by one terminal and it was going into an input terminal, not the +24vdc terminal. In my chasing I also realized that the common between all the axis terminals were not always ringing out with continuity, so I jumped them all together. I don't know it if really helped anything, but it certainly isn't hurting anything.

Anyway, was playing around with tuning again last night. I think I have the X and Z nailed, however the Y is fighting me... I Just need to figure out how to fixture the 1-2-3 blocks better.

https://photos.google.com/share/AF1...?key=OEZHX1BHX3VhOHJfR1NJV2VnM3MwcmwwdkIzWmJn

Let me know if the video doesn't work...

PZ
 
phazertwo said:
That's very interesting. I had a similar issue when I first started running the Acron and it was very frustrating, I chased it back to a miss wired +24vdc on the input strip. I missed it by one terminal and it was going into an input terminal, not the +24vdc terminal. In my chasing I also realized that the common between all the axis terminals were not always ringing out with continuity, so I jumped them all together. I don't know it if really helped anything, but it certainly isn't hurting anything.

Anyway, was playing around with tuning again last night. I think I have the X and Z nailed, however the Y is fighting me... I Just need to figure out how to fixture the 1-2-3 blocks better.

https://photos.google.com/share/AF1...?key=OEZHX1BHX3VhOHJfR1NJV2VnM3MwcmwwdkIzWmJn

Let me know if the video doesn't work...

PZ
Click to expand...

How much backlash are you seeing per axis? I haven’t really fine tuned my setup yet but previously I had two thousandths backlash in all axis, . I intend to pull apart the X end nut/ double bearing assembly ( what’s its name ? ) and see if it is assembled / designed correctly. My hope is it isn’t so I can machine up new ones with a proper gap between two angular contact bearings. I’ve heard of some cheap bearing blocks that don’t have any gap which negates the value of two angle contact bearings. Fingers crossed...
Jake
 
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I'm seeing about 0.0005". At least that's what I measured the X and Z to be, and when I entered it into backlash comp it was dead on. I can jog all over the place and it's always dead on. I have a little more testing that I need to do to be sure, but I feel I'm 95% of the way there on those two axis. Y axis is a whole different issue.

0.002" is quite a bit, I seem to remember that Acorn can only really handle 0.0015" compensation. Take a lot of pics when you tear it down, I'd really like to see what it looks like. I am willing to bet they leave a little to be desired, and re-engineering and machining them would be a fun project to upgrade the mill.

PZ
 
Guys,
I came home to a prize. My cylinder and valve for the power drawbar was delivered. I've included a pic of them. The one thing I'm concerned about is the weight. The cylinder weighs 13.8 lbs. I'll have to see what kind of affect it has on the z axis. Thoughts? Take a look: IMG_0731.JPG
 
That thing is HUGE! 13.8lbs seems like a lot of weight to add to the Z axis, but I think you'll be fine, just slow it down a bit. I think a slower Z would be well worth the power draw bar! I'm very interested to see how this projects comes together, the time it takes to change a tool on these mills is defiantly painful.

If the Z works out to be too slow, you can always get a bigger Nema 34 stepper motor to drive the Z. I'm pretty sure the stepper drives can drive a much larger motor.

PZ
 
Well guys, I just went thru an exercise of frustration. I finally fired everything up and the Acorn board didn't have a pulse. Jake, I looked at the post that you sent earlier and tried a couple things. I thought I had a bricked card. But when I removed all of the connections but the power and the Ethernet cable and turned everything on, I got the blue pulse light and was able to communicate with the card. I then went thru and set the leadshine config thinking that since it was still set to bench test that it might affect the board. Once I hooked everything back up (and I double checked all of the connections) I turned it on and it did not respond. So no pulse again. It was getting cold in the garage so I came in. Tomorrow is another day... Fun times.
 
pburgh said:
Well guys, I just went thru an exercise of frustration. I finally fired everything up and the Acorn board didn't have a pulse. Jake, I looked at the post that you sent earlier and tried a couple things. I thought I had a bricked card. But when I removed all of the connections but the power and the Ethernet cable and turned everything on, I got the blue pulse light and was able to communicate with the card. I then went thru and set the leadshine config thinking that since it was still set to bench test that it might affect the board. Once I hooked everything back up (and I double checked all of the connections) I turned it on and it did not respond. So no pulse again. It was getting cold in the garage so I came in. Tomorrow is another day... Fun times.
Click to expand...

I would just connect one element at a time. For instance just wire up the E stop. Fire up Acorn and see if you still get a pulse. Then add in the Limit switches. Check for pulse, then home switches, and so on. Until it stops giving you a pulse. Even if items aren’t connected you should be able to do a custom setup and disable the items in the wizard. It’s possible you don’t need to disable things in the wizard. I’m. Not sure. But just go one by one. That should allow you to isolate the issue.
 
This is exactly what happened to me when I had the +24vdc in the wrong terminal on the input strip. The way I found the problem was by disconnecting each one of the terminal strips except the power. Then I re-connected them one at a time and connected to the Acorn through the Wizard. Eventually I found that with the input strip plugged in that it wouldn't connect. At that point it was easy to see that the +24vdc was in the wrong spot, moved it to the correct spot and she fired right up. Good luck!

PZ
 
Hey Guys,
I found the issue. Now I have to find how to fix it. It has to do with the VFD. When I remove it from the setup the board works normally. I wired it removing the original relays from the setup. I used the second diagram that Jake provided above. This also falls in line with a generic schematic that Centrioid provides with the Acorn schematics except they use the VFDCommon. I have to dig into the plc on the vfd and see if there are any parameters that were set for mach and the nmotion board. i'm suspecting the 2 speed control settings. I have to see if there is a way to get a config page to see what's been set, or i'll have to go thru the different settings to see the value. I also noticed that when I bumped my x, y and z that they were reverse. there should be a setting in the wizard to reverse that. Any suggestions would be appreciated.
Regards,
Doug
 
pburgh said:
Hey Guys,
I found the issue. Now I have to find how to fix it. It has to do with the VFD. When I remove it from the setup the board works normally. I wired it removing the original relays from the setup. I used the second diagram that Jake provided above. This also falls in line with a generic schematic that Centrioid provides with the Acorn schematics except they use the VFDCommon. I have to dig into the plc on the vfd and see if there are any parameters that were set for mach and the nmotion board. i'm suspecting the 2 speed control settings. I have to see if there is a way to get a config page to see what's been set, or i'll have to go thru the different settings to see the value. I also noticed that when I bumped my x, y and z that they were reverse. there should be a setting in the wizard to reverse that. Any suggestions would be appreciated.
Regards,
Doug
Click to expand...

Hi Doug,
So you have 5 wires going from the Acorn to the VFD and it’s causing the Acorn to not have a heart beat ?
Jake
 
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