PM25-MV CNC Conversion kit Help

[Colt4587]

Good Morning Everyone!

I've got a PM-25MV on the way that I'd like to convert to CNC operation. I've spent the past two weeks doing research on what motors and drivers I should get. I've looked at the kits from Automation Tech Inc, and have also piecemealed parts between them and Amazon. I just recently found this kit on Ebay:

https://www.ebay.com/itm/FEEE-Ship-3...WWBu:rk:9:pf:0

I was wondering if that would work for my purposes? My purposes being a Hobby Mill, I don't really expect it to be super fast or anything. My thought process is with the money I save going with that Kit I could upgrade to a USB or Ethernet controller, or save for better tooling/touch probe.

Comments and Criticisms much appreciated, including links/lists for better kits.

Thanks!

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[maxspongebob]

Precision Mathews makes some nice equipment. I love my PM1228 lathe. That being said, this mill looks almost the same as a G0704 from Grizzly. When I converted my G0704, there was a good bit of modification required to the machine itself. The configuration of the ball screws will require some grinding of the saddle and maybe the table. For these reasons I would choose a conversion kit first and then think about all the rest of the parts after that. Choosing a controller and the CAM software is also more important than the actuators selected. Some controllers are compatible with Mach 3/4 some are not.

That conversion kit from Automation Tech looks like a nice one. Double nuts is good for backlash, but may require more mods to the sadle and base. I chose to put my Y axis motor on the back instead of the front.

Don't forget:
Couplers
Limit switches
E-Stop switches
Control switches at the mill to stop/start/pause a job
Cabling
Enclosure
Spindle controller
Lubricant/Mist/Flood system
Tooling, you will want to look into TTS, something that is indexable.
A pendant

https://www.cnczone.com/forums/bench...are-posts.html

[Colt4587]

Thank you for the reply!

From the information that I have gathered across the web. The PM25 is similar yet not the same as the Grizzly G0704. One of the reasons I went with the PM was that it wasn't going to require any modification to get the kit to work with it. I plan on getting the kit from Automation Tech Inc. (I'm also a newbie to this, so please correct me if I'm wrong )

So for me it's just a matter of settling on the electronics currently. There is a lot of information out there and I'm just a little bit overwhelmed with the correct motor, driver, and controller combination. If it's helpful I plan on going with LinuxCNC but would love to be able to also do Mach3 if I hate the LinuxCNC matchup. I also need to keep in mind that this is just a hobby home use mill, so I don't need it to be super fast or overkill.

I really appreciate the list! Some of that I already have, some I need to get, and some I am planning on getting in the future.

[maxspongebob]

Looking at the Automation Tech kit, it says that Saddle modifications are not needed. Thats good. I wonder if the double ball nuts reduce the Y axis movement at all?

[maxspongebob]

I was looking at Linux CNC as well when I started my conversion. I quickly found that there are a lot more electronics available for a widows type system. I use Mach 4 paired with a Pokeys 57CNC controller. If I had it to do again, I might choose the Ethernet Smooth Stepper.

Using Mach, 3 or 4 IMO, gives you more options integrating with other hardware and software. I would recommend that you look on the web for stuff like a pendant that supports Linux. Unless you are planning on building a console or control panel, a pendant is a must have for material setup and job control.

[maxspongebob]

Also, I found this item that will let you interface with the PM spindle controller. https://procutcnc.com/product/pm-25m...control-board/
That will help.

[Colt4587]

Also, I found this item that will let you interface with the PM spindle controller. https://procutcnc.com/product/pm-25m...control-board/
That will help.

Awesome! Thank you

[109jb]

As for the initial question. That ebay stepper kit is not a good choice as far as I am concerned. I actually have one machine running those 425 oz-in motors with DM542 drivers. On my application they work great, but I would not recommend them for a G0704/PM25 machine. The absolute best choice in open loop steppers for these machines is the 570 oz-in steppers. I have a G0704 with them. I have Automation Tech KL-6050 drivers but if I were doing it today with the 570's I'd use the digital KL-5056D/E drive. As for the Z, that ebay 1600 oz-in motor is gross overkill. Non of the motor specs are listed on the ebay ad, so the inductance could be very high amking them dogs for performance. My G0704 has another 570 oz-in motor and does fine, but when drilling I have to be careful. If I dit it again I'd use one of the AT 906 oz-in steppers paired to an appropriate digital stepper driver. In short, pass on the ebay stepper kit.



As for the posts that followed the initial one, let me start by saying that I interpreted you to mean you want to get started at least with budget in mind. For this reason I have these things to say.

Don't discount a LinuxCNC system based on what was said. A LinuxCNC system paired with inexpensive Mesa hardware is hard to beat in terms of performance, IO, or price. Sure there are more electronics available for windows systems, but how many electronics do you need for a CNC setup? last I checked only one was required. The fact that you can buy many different brands for the windows controllers should not sway the decision because the Mesa is all that is needed with the LinuxCNC system. There is a reason that Tormach went with a Mesa/LinuxCNC system and left Mach3. LinuxCNC is rock solid stable as well as free. Depending on the performance you want an old PC with a parallel port may be all you need for electronics anyway. If a theoretical 0.0001" resolution and 150 IPM max rate is good enough for you that is only 40kHz step rate which is achievable using a parallel port.

One of these posts also implied that pendants for LinuxCNC are hard to find, well this one that is all over Amazon and ebay works.



and here is how to incorporate it in LinuxCNC: LinuxCNC Documentation Wiki: Using A XHC-HB04 Wireless MPG Pendant

Saying a pendant is a "must have" is not true either. The keyboard controls on LinuxCNC and probably any of the Windows based controllers are very easy to use and I still don't have a pendant connected to my machine. Would a pendant make some things easier? Sure, but "must have" and "nice to have" are really different descriptions.

So taking the list previously posted and actually listing things that you really "Must have" to get a machine like a G0704/PM25 running under CNC we have:

Couplers - Must have
Limit switches - You can get the machine running without them using software limits. Then you can use the CNC to make brackets if you want to.
E-Stop switches - Need to have one on the driver box at least, but could be added after basic machine is up and running
Control switches at the mill to stop/start/pause a job - Not strictly needed. Keyboard shortcuts on the PC do all of this just fine.
Cabling - Sure Needed
Enclosure - Not initially needed or really ever in reality. Another nicety that can be added later if wanted enough.
Spindle controller - Not a necessity. You can turn the spindle on/off just like a manual mill and still operate in CNC
Lubricant/Mist/Flood system - Very nice to have but you could use a squirt bottle from the dollar store and a hand oiler for a long time.
Tooling, you will want to look into TTS, something that is indexable. - This all depends on what you want to do. TTS is an option, but I prefer standard R8 tooling, and most of the time I use HSS end mills and very little indexable tooling even though I have them.
A pendant - Already discussed. Not a necessity, but rather a nice to have.

If you really are on a budget you can control the machine with a $5 Arduino microcontroller loaded with the free firmware Grbl using one of many free windows, linux, mac, Andriod, Iphone or web based interface programs over USB, Wifi or bluetooth. This would be good for 0.0001" thoeretical resolution at 120 IPM on a standard Arduino Uno. The interface hardware used can be just about anything that can send serial data to the arduino since the arduino is what is performing all of the realtime calculations. You can check it out here: https://github.com/gnea/grbl/wiki

[109jb]

Also, I found this item that will let you interface with the PM spindle controller. https://procutcnc.com/product/pm-25m...control-board/
That will help.

The website says : "This option is only available in the servo motor controllers. Options is not available for stepper motor controllers. " and indicates it is designed to interface with their own control boards. I would be leary as to whether it will work on a generic board.

Many breakout boards include electronics on the board for various spindle control. My $6 parallel port board can do PWM or 0-10V. The 0-10V option can be wired directly in place of the motor controllers potentiometer (the one the speed knob is connected to) for spindle control. If your parallel port board doesn't have this, then this is a cheaper option than the above:

https://cnc4pc.com/c41s-pwm-variable...rol-board.html

[Colt4587]

Couplers - Must have
Limit switches - You can get the machine running without them using software limits. Then you can use the CNC to make brackets if you want to.
E-Stop switches - Need to have one on the driver box at least, but could be added after basic machine is up and running
Control switches at the mill to stop/start/pause a job - Not strictly needed. Keyboard shortcuts on the PC do all of this just fine.
Cabling - Sure Needed
Enclosure - Not initially needed or really ever in reality. Another nicety that can be added later if wanted enough.
Spindle controller - Not a necessity. You can turn the spindle on/off just like a manual mill and still operate in CNC
Lubricant/Mist/Flood system - Very nice to have but you could use a squirt bottle from the dollar store and a hand oiler for a long time.
Tooling, you will want to look into TTS, something that is indexable. - This all depends on what you want to do. TTS is an option, but I prefer standard R8 tooling, and most of the time I use HSS end mills and very little indexable tooling even though I have them.
A pendant - Already discussed. Not a necessity, but rather a nice to have.

https://cnc4pc.com/c41s-pwm-variable...rol-board.html

Thank you so much for the reply!

I ended up not doing the Ebay kit and just spent the money to get the right motors off the bat, rather than trying to shoe string it in

I ended up getting these motors for the X/Y:

NEMA23 570oz/in 5A 3/8” Dual Shaft Stepper Motor (KL23H2100-50-4B)
https://www.automationtechnologiesin...lat-570-oz-in/

This motor for the Z:
NEMA34 Stepper Motor – 906 oz in 6.1A Single Shaft (KL34H295-43-8A)
https://www.automationtechnologiesin...l34h295-43-8a/

I also ended up getting the UC300ETH and the Leadshine MX3660. I know it's more money up front, but I think it's gonna save me some heartache in the future. I'm not going to write of LinuxCNC off yet, and if I do end up not liking UCCNC or Mach3, I have other machines that I can put the UC300ETH on.





So I believe the kit already comes with Couplers. I tried calling them but the lady on the phone didn't know and asked me to shoot them an email, which I have done.

Thanks again!

[109jb]

By all account the MX3660 is a good choice. As you say, more money but eases things a bit. I have heard good things about the UC products but have no personal experience. I have also read many times in threads where Mach users who have switched prefer the UCCNC software.

Good luck with your conversion and report back with progress and any further questions.

[Colt4587]

Thank you! Like I said, I'm super appreciative of all the help. I'm going to hopefully document my conversion and will definitely be sharing it here!

Thanks again!

[rmachinist]

i have started my cnc conversion i made a few videos and more to come: