New PM-25MV Mill

Sounds like a great idea. Learning is much easier in manual (in my opinion) because you can feel when something isn't quite right. Lifting it wasn't too bad while it was taken apart, but I am 22 and in decent shape, not sure what your situation is, but keep that in mind.

If you end up converting it to CNC, let me know and I can send you the plans for the conversion parts. This machine was way easier to convert than my X2, and all of the parts can be made manually. Let me know if you have any questions when you get the machine, I am always happy to help!

I'm a little past 22 ( by about 46 years!!) but i have mastered the art of fulcrum leverage to lift stuff around the shop.

I picked up a rolling workbench/storage cabinet from HF the other day and it will serve as the new home for the mill. I'm still working to attach it to the wall and getting the top leveled. I make a few specialty tools for the HD Ironhead Sportsters so having a mill will be a welcome addition to the shop. I've done some basic work with my brothers older Grizzly machine, but I'll be doing a lot of try this and try that plus a whole lot of Internet looking.

Thanks for the offer for help and info. I'm sure that after I get my machine set up next week I'll have a lot more question than I have answers. lol
 
When I bought my PM25 I was 6 years younger than I am now (62), and while I managed to wrap the thing in a beach towel and lift it onto a 40" tool box, it is not something I recommend folks do. My wife about had a fit. ;)

I put 3/4" plywood on top of the tool box, and then a piece of 1/4" plate between the mill and the toolbox. Made some screw-type levelers to get the toolbox up off it's wheels and it turned out to be a decent setup.

Have fun with your new mill. :)
 
When I bought my PM25 I was 6 years younger than I am now (62), and while I managed to wrap the thing in a beach towel and lift it onto a 40" tool box, it is not something I recommend folks do. My wife about had a fit. ;)

I put 3/4" plywood on top of the tool box, and then a piece of 1/4" plate between the mill and the toolbox. Made some screw-type levelers to get the toolbox up off it's wheels and it turned out to be a decent setup.

Have fun with your new mill. :)
If you didn't take it apart first, that is really impressive! I could hardly move the thing while it was all in one piece.

What kind of tool box do you have your mill on? I am going to build an enclosure for mine, but I can't decide if I want to make the base or buy something.
 
If you didn't take it apart first, that is really impressive! I could hardly move the thing while it was all in one piece.

What kind of tool box do you have your mill on? I am going to build an enclosure for mine, but I can't decide if I want to make the base or buy something.

I no longer have the mill, and yea, I picked it up as one piece. The beach towel was necessary as I used my forearms like a forklift under the table and put the back of the column against my chest. I was in my mid-50s at that time, and probably shouldn't have done that. I was fairly strong most of my life, and old habits die hard. At least I didn't drop it on my foot... :D

Going back through my old pics, I found one that basically shows my PM25 setup. It's on a Craftsman 40" toolbox.

DSCN4203.jpg


I don't have a pic of the levelers I made, but they were similar to a machinist's jack. Put on on each corner of the toolbox. The setup worked really well for me. If you have more questions, lets take this offline so we don't continue to hijack the OP's thread. :)
 
I no longer have the mill, and yea, I picked it up as one piece. The beach towel was necessary as I used my forearms like a forklift under the table and put the back of the column against my chest. I was in my mid-50s at that time, and probably shouldn't have done that. I was fairly strong most of my life, and old habits die hard. At least I didn't drop it on my foot... :D

Going back through my old pics, I found one that basically shows my PM25 setup. It's on a Craftsman 40" toolbox.

View attachment 259202

I don't have a pic of the levelers I made, but they were similar to a machinist's jack. Put on on each corner of the toolbox. The setup worked really well for me. If you have more questions, lets take this offline so we don't continue to hijack the OP's thread. :)

Thank you for the info. I like that set up a lot, very organized and clean. No worries about the OPs thread, its mine and this is right on subject.
 
I made some new lock nuts and machined some spacers for the AC bearings. I suspect some of the .008" backlash was coming from the bearings I was using and I don't think they were preloaded properly. I made 2 piece nuts with screws that can be tightened to lock the nut down on the threads. These are much better than the lock nuts that came with the ballscrews and in my opinion, they are better than the nylon lock nuts. Since it was an M12x1 thread, I couldn't commercial nuts for it anywhere anyway. They use 3 4x40 screws to lock and I cut the holes so there was just a little bit of space between the nuts when the holes are aligned. I have always had trouble with the regular lock nuts occasionally loosening up and it has ruined parts before. I am confident that these won't move once locked.
uqIknFp.jpg

Here it is installed on the X axis with the new coupler on the motor.
LoYBt5N.jpg

I machined some spacers so I could preload the AC bearings as well. That was pretty straight forward but I don't have any pictures of it. Essentially I machined a bar to the right inside and outside diameter, then parted off 3 pieces, then super glued each to a piece of steel in the spindle, and faced it until it was about .05" thick. Using the lock nuts, I can adjust the preload on the bearings without needing shims.

I have the tool changer mostly designed now. It will be a little while before I am ready to start making parts for it, but I will start ordering stock and parts soon. The plan is to use a Nema 23 motor, a deep groove ball bearing, some round linear rails, and a pneumatic cylinder to run it. I think I will use an arduino to control the changer if I can figure out how to interface it with LinuxCNC. The plan is to have several sensors checking each step of the tool change to ensure reliability.

The tool change will go like this:
1. Z axis return to home position (Home switch confirm head in position)
2. Spindle motor off (Relay on spindle power to ensure spindle motor off)
3. Tool changer move into position below spindle (sensor to confirm changer in position)
4. Z axis lower tool to tool changer (sensor confirm head lowers to tool tray)
5. Pneumatic cylinder release tool (sensor to confirm cylinder actuates)
6. Z axis return to home position (home switch confirm head in position)
7. Tool changer rotate to the next tool (sensor to confirm position of carousel and proper tool selected)
8. Z axis lower spindle to tool (sensor to confirm head lowers to tool tray)
9. Release pneumatic cylinder (sensor to confirm cylinder releases)
10. Retract tool changer (sensor to confirm tool changer fully retracted)
11. Z axis return to home position (home switch confirm head in position)
12. Confirm new tool in spindle (not sure how I will do this yet)

Here is the tool changer with all of the covers removed.
u7p1we0.png

Other side.
xyCSUXl.png

On the mill.
dFPyLL7.png

I used Fusion360s FEA to make sure the changer wouldn't deflect too much under the weight of all the tools. It gave me a deflection value of .0002" at the worst position so I am confident the structure is strong enough.
svWJZCj.png

With a vise installed, there will only be about 5.5" between the bottom of the tool holders and the top of the vise jaw. I am considering a few alternatives such as adding a Z axis to the tool changer so it lifts up and out of the way when not in use, and the table can move all the way forward (closest to me) when changing tools, so hopefully it will be mostly out of the way. I don't think it will be too much trouble though, since I don't plan to have any tools sticking out more than 2 inches, and I don't often work with parts sticking more than 3.5" out of the vise. Im pondering the idea of some kind of quick release for the tool changer so I can lower the tool carousel out and remove it completely for when I work with taller parts.

If anyone has any ideas or suggestions, I am all ears. I have never tackled a project like this and could use all the help I can get.
 
Quite the project you have going here. It will be interesting to see this thing in action when you get it done. :)
 
Arduinos are nice, but considering the amount of I/O you are talking about, it seems it would be very beneficial to up to a full PLC. It would open up a lot of I/O and have the advantage of being very expandable.... Plus they are industrial devices, so they should last forever on a hobby mill.

I would suggest looking into a Click PLC from automation direct (Starts at $69). They are crazy cheap for the quality you get, the programming software is FREE, and you have tons of add on capacity (digital I/O and analog). I have used them a few times for smaller projects at work and they seem to work out very nice. I plan to install one on my mill to automate things like the motor fan, cabinet fan, coolant level sensor, PDB safety (sensing if spindle is spinning, possibly tool in spindle/not in spindle). Relatively simple things that I don't need to tie up I/O on my Acorn board with, though it will take up at least 1 input for an error condition. One could even add an HMI for better visibility and control.

Here is a link the the PLC, and a cheap HMI to go with it... if your into that kinda thing...
https://www.automationdirect.com/clickplcs/index

https://www.automationdirect.com/ad...els/3_inch_Panels_-a-_Accessories/EA3-S3ML-RN

Just a thought.
PZ
 
Arduinos are nice, but considering the amount of I/O you are talking about, it seems it would be very beneficial to up to a full PLC. It would open up a lot of I/O and have the advantage of being very expandable.... Plus they are industrial devices, so they should last forever on a hobby mill.

I would suggest looking into a Click PLC from automation direct (Starts at $69). They are crazy cheap for the quality you get, the programming software is FREE, and you have tons of add on capacity (digital I/O and analog). I have used them a few times for smaller projects at work and they seem to work out very nice. I plan to install one on my mill to automate things like the motor fan, cabinet fan, coolant level sensor, PDB safety (sensing if spindle is spinning, possibly tool in spindle/not in spindle). Relatively simple things that I don't need to tie up I/O on my Acorn board with, though it will take up at least 1 input for an error condition. One could even add an HMI for better visibility and control.

Here is a link the the PLC, and a cheap HMI to go with it... if your into that kinda thing...
https://www.automationdirect.com/clickplcs/index

https://www.automationdirect.com/ad...els/3_inch_Panels_-a-_Accessories/EA3-S3ML-RN

Just a thought.
PZ
I will have a look at them. The reason I picked arduino is because I already have 2 arduino megas, and they have 54 input/output pins and should have more than enough for the sensors and driving the stepper. I am also already familiar with the programming language, and they are cheap, so I can blow them up without feeling bad about it. It also has digital and analog I/O, can (in theory) communicate with the PC through the serial port, and has a bunch of add ons that are cheap and easy to use.

I'll look at those PLCs in more detail, though I am not entirely sure what they do... At the very least, they look beefy and well made, which would be a big plus.
 
PLCs are basically small industrial computers. Pretty much anything that is automated has a PLC these days, even the Acorn controller that I'm running is considered a PLC with a Beagle Bone computer piggy backed to it. Programming them is incredibly easy, no experience with any type of C programming is needed.

I used Arduinos a lot in the past, but after finding this Click PLC, I've pretty much given up on them. PLCs are optically isolated, so you have to try pretty hard to blow one up (and I have tried). I do have quite a bit of experience with them through work... so that helps too. As with most things these days there is an incredible amount of material on YouTube to walk you through almost anything you need to know with them.

PZ
 
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