[4]

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

[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#1
Originally, I was going to CNC a PM-940m with hardened ways from the ground up. When I started to gather the components for the build, I ran across the Centroid Acorn controller, and that was the first component I purchased. But during the course of starting the process, I decided to switch gears and purchase a turnkey machine instead and give that a try. Once I received the machine and checked out the nMotion controller with Mach 3, I decided to switch it out with the Acorn controller. One reason was that there is not a lot of information on the nMotion controller, and another is that I don’t have any experience with Mach 3. With all of the issues that I’ve read about Mach3, I decided to focus my efforts on switching to the Acorn controller and becoming familiar with the Centroid control software. This thread will document the process and I hope that others who have similar machines and want to change the controller/software will benefit from the information gathered here. Please feel free to share your knowledge and opinions during this process.
There is a wealth of information on the Centroid Acorn site page and Centroid’s Acorn forum. I will post the links below in the outline to get this started.

The general outline will be as follows:
  • Gather information on the Centroid Acorn setup
  • Compare and match the nMotion schematics to the Acorn schematics
    • Identify wiring matchups and changes needed. Determine what’s missing (5v power supply, momentary jog contact for limits)
    • Know that the wiring numbers may vary from machine to machine (thanks Jake)
    • This link to a post I created in the forum will fill in some of the info from questions that I had: http://centroidcncforum.com/viewtopic.php?f=60&t=1270
    • Document the changes needed for getting motion working on the machine with peer review
  • Focus on the Spindle/VFD setup
    • Formulate and verify the necessary changes through peer review
    • Test Spindle function
  • Look into adding flood coolant pump, lube pump, etc to outputs
I have already setup my computer and have bench tested the Acorn card according to the instruction videos. I followed Centroid’s recommendation on setting up an Intel NUC with Windows 10 Pro and I’m using a Viewsonic 24” touch screen monitor.
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#2
YES! Sub'ed and can't wait to see this thing in action!

I hope to be only a step or two behind you in this whole process! Building my new computer tonight!

PZ
 

cut2cut

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Dec 21, 2016
Messages
194
Likes
30
#3
Yup, right there with you both! I already have my computer setup and the 5v+24v power supply. Just waiting for the Acorn which should show up by the weekend. Cheers !
Jake
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#4
Great to hear guys! I'm pondering on how best to mount the new card in place of the nMotion card. I'd like to mount it perpendicular to the back board so i can leave space for a 4th axis drive if i go that direction. How are you all looking to mount yours?
Regards,
Doug
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#5
Hey All,
Here is a good video that I found on you tube giving an overview of using the Centroid software:

Enjoy!
Doug
 

cut2cut

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Dec 21, 2016
Messages
194
Likes
30
#6
Hey All,
Here is a good video that I found on you tube giving an overview of using the Centroid software:

Enjoy!
Doug
It is very good ! By coincidence I watched it this morning!
Good news, I have the Acorn moving all axis and also the spindle is spinning, and the e-stop working.
Initially I had not run the 24v jumper so the E stop was not functioning but would almost work but only upon restart of the program.
Unfortunately the E stop switch that comes with the PM940 does not mechanically function as Normally Closed. It has only two wiring terminals. The default wiring for the limit and home switches is also NO. I am not sure if they can be wired as NC as that’s preferable. Something to check.
The axis direction and axis STEP and DIR had to be inverted in the setup wizard, yours may not?! Also currently the spindle appears to be spinning the wrong direction but I need to verify that. There doesn’t appear to be a software fix. Likely two of the motor wires just need to be swapped on my 3 pole inverter motor.

More details to follow. The most pressing issue for me is to figure out why it persistently runs a default flange program when I hit the cycle start button. I have to quickly hit cycle stop which aborts the job, then I can jog around.

Anyway, good progress today, but hit a few snags, but nothing bad at all.

Jake
 
Last edited:

cut2cut

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Dec 21, 2016
Messages
194
Likes
30
#7
HUGE note to avoid a crash while setting the software up or if you want test new hardware without it running a job. EVERY time you hit cycle start Centroid CNC software v12 will open the last job file you used. In my case it was "FLANGE. xxxx " something like that. It was probably loaded by the person that tested my card at the factory, or maybe its the default? Regardless, while you are troubleshooting the conversion to Acorn, you'll undoubtedly need or want to jog around to see if things are working you'll have to hit "cycle start ". What happens right away is it will load and start performing the last job / program you loaded. It will persist. This is a good function as it doesn't require you to find a file before continuing with the job you started the day before.

The solution is to create a "--NULL--" file that you load. It shouldn't have ANYTHING in it. Then you'll just load that file after you are done with a real "job/program" Thankfully someone posted that solution in October.

Note: I have not turned on "Home to Switch" yet, so this may change the behavior possibly?

Jake
 
Last edited:

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#8
Good to know Jake, thanks for the heads up on all of this. That's fantastic that you've made this much progress. It's been unusually cold here in Florida, so I didn't work out in the garage as much as i'd liked to yesterday. I'm hoping to get more time today and i'll check out how my limits are wired for NO or NC. I didn't ring them out yet, but I'm going to have to get into each one to determine the colors they used for each wire on the common. Plus i'm still mulling around how I want to mount everything to take full advantage of the space.
Regards,
Doug
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#9
Very interesting, thanks for the heads up Jake!

PZ
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#10
I started getting into the wiring on the 940 last night in preparation of the Acron showing up today. The limit switches can be wired NO or NC, there is an extra set of terminals inside the switch. On another note EVERY wire in my limit switches was loose, and one was even broken. No wonder my limits never worked right with M3... All better now!

Also, on my mill (ordered Jan 2016) there is a yellow wire that is not used in the step/dir cable going to the stepper drives. I Pulled that out for each axis and will use it as the enable. Also, the back plane in mine had holes for the drives to be moved to the right, I would assume to make room for the 4th axis. I went ahead and moved the drives over to create a little extra room for the Acorn. I'd post pics but it looks like the local squirrel population did a number on the phone line going into my house... So my interwebing is reduced to what I can do on breaks at work...

PZ
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#11
Hey PZ, great to hear that you're all set. And thanks for the info on the switches. I guess by having to do this we'll have better mills from the experience. I know that the qc on mine isn't what I would have expected. Things being loose and all. I also have a wire going to the swingarm control box that is just cut off in the control cabinet. But hey what can we do. Did you see the post in the thread from the Centroid site? One of the techs there responded and said we didn't have to use the ENA feature if it wasn't used in the mill. Don't know if that makes a difference, but it's there.
Regards,
Doug
 

cut2cut

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Dec 21, 2016
Messages
194
Likes
30
#12
Nice finds PZ ! Sorry about the squirrels :-(

guys, check out this video of a centroid software feature. This is awesome ! Now I'm researching probes again... damn expensive, but ....


Jake
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#13
Hey PZ, great to hear that you're all set. And thanks for the info on the switches. I guess by having to do this we'll have better mills from the experience. I know that the qc on mine isn't what I would have expected. Things being loose and all. I also have a wire going to the swingarm control box that is just cut off in the control cabinet. But hey what can we do. Did you see the post in the thread from the Centroid site? One of the techs there responded and said we didn't have to use the ENA feature if it wasn't used in the mill. Don't know if that makes a difference, but it's there.
Regards,
Doug
Yeah, I'm honestly not sure what the enable circuit does for you... but I figure it's there, the wire is there, and it's in the Acorn wiring diagram I'll hook it up and see if she chooches.

Looks like the Acorn was delivered... I can't believe how excited I am about this, it's like I'm 5 years old and it's Christmas day!

PZ
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#14
I tell my wife every day is Christmas. She tells me that the only difference between men and boys is the price of their toys. :) I hope it all meets your expectations. I have a good feeling about this product.
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#15
Nice finds PZ ! Sorry about the squirrels :-(

guys, check out this video of a centroid software feature. This is awesome ! Now I'm researching probes again... damn expensive, but ....


Jake
Jake,
Alan has some good videos. He seems to be very happy with Centroid and Clear Path. I purchased the basic probe from Tormach to give it a go. But I came across probe called a Hallmark that's made by a guy in New Zealand that might be at a better price point than say one from Centroid. Here's a video of how he came about it. There are others showing his development of the probe.
I think it goes for between 600 and 700 dollars.
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#16
I have been keeping half an eye on the Hallmark ITTP (Impact Tolerant Touch Probe). It looks like a nice probe, but I thought he wasn't really selling them yet? Either way it's on the list of tools that would be nice to have, especially with the probing routines available in CNC12.

Got my Acorn bench tested last night, and modified the cabinet so the Acorn will be mounted near the same location as the old nMotion. Couldn't find standoffs to get it mounted though, so I had to call it a night. Hoping to pick some of those up on the way home tonight, get the Acorn mounted in its new home, mount the new 5v power supply and see if I can get some motion out of it!

Also, Jake was defiantly correct about the e-stop on the 940 being a NO circuit... which is super sketch. China never ceases to amaze me with corner cutting. I can't imagine there is much of a cost savings in using a NC switch instead of a NO switch, and with the nMotion and M3, its just a flip of the active high/low on that input to change it... Anyway, lucky for me I happen to have a few switches from some equipment that I scrapped, but important for others doing the swap to know, you will need to replace the e-stop with a NC. Actually not a bad idea to switch it out anyway, a NO e-stop circuit is dangerous.

PZ
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#17
hey PZ, thanks for the heads up. I really didn't want to have to change things around that much with the limits, but oh well. I actually bought a new Estop switch when I bought my Acorn and was going to do the machine from scratch. Looks like i'll have to put it to use. To save room I made a backing plate for the controller and i'm going to stand it off of the main board around 3" with all thread. Underneath that i'm going to mount the power supply against the main board. Hopefully I wont get any interference. This way i'll have the space to add another drive if needed.
On the probe, do a search on YT. There is a guy who just reviewed the Hallmark so I think they are for sale. I'd like to get the one from Centriod, but I want to get some experience with using one of these before i'd go with that amount of money (and the big boss would kill me). They are expensive, but i'm sure they are high quality.
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#18
Looks like he is taking email orders...I don't really want to inquire about one since I cannot afford it at the moment, but it would be nice to know how much it costs.

This is the video that made me dig deeper into it. The CNC4RX7 guy seems to make some decent, informative videos.


PZ
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#19
Yeah, Sam is very good researching stuff. When I was going to build my CNC 940, I purchased his plans and documentation to give me a jump on trying to gather all of the info. I think it was $40.00. I don't mind contributing some when folks give you good info. Helps save time. Even though he did the 727, a lot of what he did translated to the 940. For the probe, I did see some pricing down in the comments on one of the videos. Not sure if it was Sam's.

Regards,
Doug
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#20
Hey Guys, finally starting to make progress. I got the power supply and controller mounted in the cabinet the way I wanted. I wanted to try to maximize space for a future 4th drive. But also wanted to be sure that the power supply won't interfere with the controller. I hope to get things wired in the next couple nights. Hopefully i'll be able to use the existing shielded cable, but I may have to buy some more. I posted some pics on how they are mounted.
 

Attachments

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#21
PZ, Sam has the price listed at the top of his video. Here's what he has listed:

Published on Aug 5, 2017

In this video I am excited to show you the Hallmark Design Ltd. Impact Tolerant Touch Probe. This Touch probe is made specifically to provide precision and accuracy while being Tolerant of impacts in all directions. ( NO MORE BROKEN STYLUS) I was selected as a Mach 3 user to do some beta testing, The probe was originally designed for the Tormach PCNC machines. As you know Mach3 does not come standard with Auto probing routines and the few I found on the Zone were not what I was looking for so I have modified these extensively to work well with the I.T.T.P. Some testing is still needed but as shown in the video they work quite well. If you would like more information you can contact me. Please comment and let me know if the content is spot on or you would like more information and details.Thanks for watching , please subscribe, thumbs up if you like the video, and most importantly , Be Safe!

Pricing: $695 $20 shipping to USA
Contact info: https://www.youtube.com/user/Threadex...
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#22
Wow, that's about half cost of the Centroid DP-4... But still way more than the cheapo Tormach unit. Hopefully you get what you pay for and judging by Sams review, you do.

It would seem that your panel layout is quite a bit different than mine. Can you snap an overall shot of the cabinet layout, I would like to see how yours is done. If I ever get my internet situation figured out I'll post some pics of how I mounted mine.

PZ
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#23
Hey Guys,
Did you have to do anything to switch input voltage on the meanwell power supply? I don't see a selector switch, and there is notihing on the online doc, so i'm assuming it's auto-ranging.
Regards,
Doug
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#24
Hey Guys,
Did you have to do anything to switch input voltage on the meanwell power supply? I don't see a selector switch, and there is notihing on the online doc, so i'm assuming it's auto-ranging.
Regards,
Doug
Is the voltage out of range? I checked mine before I bench tested and it was 24v on the nose. Also, looks like it might be too late for you, but I just used the 940's factory 24VDC power supply... made things a little easier and cleaner.

Anyway, I finally have real internetz at my house again! So here are some pics of how I mounted the Acorn, should leave me plenty of room for a 4th driver in the future... (let me know if you cannot see the pics, I've never posted pics like this...)
ZQwdzOP8uDXjogiuXHo2NI8aUjZaPzF-O3XRDhLnmvFqhH2LWs03EUqRpXQpnul0YRKYqwnx1bXOn5Un26L=w689-h918-no.jpg

8fTp1VJCx3YtfEtJs95c6LXIuizviQzMLdIIt6FFLGPV8rmctPTvo3lhF67eoThcofxBJP2_VTbBIiwFBQP=w689-h918-no.jpg

The system is powered up, for some reason I don't have motion, though I suspect it has something to do with the enable circuit ,hopefully I will get that figured out tomorrow. Also it turns out that you don't need to re-wire the switches, replace the e-stop, or anything, you can just select NO instead of NC in the wizard. NC is still a much better/safer way to go, so I'm still going to swap out the e-stop.

Cabinet still needs it's final clean up, but will happen after she's tested out and I'm 100% sure i'm not going to change wiring again.

Here is a link to the 5v power supply I used. I wanted something small and DIN mounted.
https://www.amazon.com/gp/product/B01HTH3LSE/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

Also, here is the E-Stop that I'm going to use. Should be a drop in replacement
https://www.amazon.com/gp/product/B0094GM004/ref=oh_aui_detailpage_o00_s00?ie=UTF8&th=1
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#25
Wow PZ, your cabinet is wired a little different than mine. I asked about the power supply because I didn't want it to be damaged if I had to manually set the input voltage. I didn't see anything that would indicate that on the new meanwell dual output voltage power supply, but I wanted to be sure that the input voltage was auto-ranging. The 24v power supply that came with the mill has a warning tag of setting the input voltage switch on the power supply, but I can't see a selector switch. I swapped out the e-stop with one with a NC contact and added a jog switch for the series limits. In the process now of switching the limits to NC and tracing out the commons so I hook them up right. Luckily there was a spare wire going to the control arm, so I was able to wire the jog switch easily. I was going to pull some extra wire to the control arm box, but it's not as easy as I suspected it would be. They used a spiral wrap on the wires and it's acting like a Chinese finger. I don't want to remove all of the wiring and pull it all back in again. So for now I'll just leave it as it is. Hopefully, i'll get some time tomorrow to work on it in the morning. it's getting cold here again, and it makes it uncomfortable to work in the garage. I'm losing my northern blood. Been in Florida too long.
Regards,
Doug
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#26
You should snap a picture of your cabinet. I'm interested to see what the layout looks like.

PZ
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
176
Likes
98
#29
Well I got mine running last night. I spent a about an hour pulling my hair out trying to figure out why the X-axis just would not go. It was making crazy noises even when it wasn't be actuated. Turns out that that A+ and B+ wires were loose in their ferrules, so it had intermittent connection. Got those re-ferruled and BOOM! SHE'S ROCKIN'!

I got the X-axis tuned, and I'm running 125 IPM on X and Y which is 25IPM faster than with the nMotion and it seems way smoother! The high today is 25°F so I'm not going to be making it out to the garage tonight. But there is light at the end of the tunnel!

PZ
 

pburgh

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Dec 14, 2017
Messages
78
Likes
10
#30
That's great to hear PZ. I'm hoping to get mine running tonight. Still have to be sure that the VFD is connected correctly. My wiring was different than Jake's, so I have to take a closer look.
Regards,
Doug
 
[6]
[5] [7]
Top