New Pm-25mv

Yes I just pull it out
That worked
Thank you so much
Tomorrow am starting my Cnc conversion

I'll post pics of the build
 
As I was building my X feed, I installed a ball bearing on left end of the table. Even before the motor got in place, I realized that that bearing reduced the friction by 1/3. I just bored a hole in the cast iron end piece of the table for the bearing.


Do you have any photos of your x-drive for the 25? and any of the bearing installation? Have seen couple of utube videos on table drives for mini-mills and Tin Barn's version
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, but nothing specific to the PM25. I've had the mill for about a month, and want to work out a reversible drive system with a clutch. Have just finished the Z drive following mrjbinok's thread, and want to use the same type of wiper motor and the 30 A power supply I already have.
 
For my Z drive, I used what looks like the same motor, but it's direct drive, 1 to 1. It doesn't have any trouble unless I forget to release the head clamps.
 
For my Z drive, I used what looks like the same motor, but it's direct drive, 1 to 1. It doesn't have any trouble unless I forget to release the head clamps.


Hi- I was asking about your table X drive-

As I was building my X feed, I installed a ball bearing on left end of the table. Even before the motor got in place, I realized that that bearing reduced the friction by 1/3.
I just bored a hole in the cast iron end piece of the table for the bearing.


Did you remove the smaller plate that is attached to the side of the table and insert a bearing into it, or make a replacement plate? This plate see a, b & c is cap screwed onto the side of the table, and I am thinking of making a replacement plate that is bored out for a sealed roller bearing.


Do you have any photos of your X table motor drive system? I am wondering how to make a clutch arrangement so that the table can free wheel and be operated by hand from the right side crank. The Z crank motor drive does not need a clutch, just have to remember to release the gibb stops....

Thanks,
















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b.JPG


c.JPG
 
For my Z drive, I used what looks like the same motor, but it's direct drive, 1 to 1. It doesn't have any trouble unless I forget to release the head clamps.


Sorry- replied to wrong thread post.

I followed the gear arrangement to limit the width of the Z motor drive, as they installed the DRO monitor close by which limited using the hand crank. The Z drive does not need a clutch like the X table drive does- just have to remember to loosen the gibb locks? I had thought of using something like a 5/8" lovejoy 075 connector with rubber bushing, but again wanted to reduce the lateral size of the motor attached to the column...

Thanks,
 
Sorry no pix. I'm in the middle of building a new computer setup, can't access the photos to send at this point. I removed and faced the outside face of the original end point. White in your pix. I believe I buried the ball bearing in both pieces, this one and the one inside. I mounted a piece of 1/2 aluminum on the outside of the above piece, I mounted the motor and controls on this plate. I fabricated a hex on the end of the lead screw and a 3/8 square on the motor drive and mounted a 3/8 drive hex socket on both. It slides back and fourth on the 3/8 square, engaging the hex to drive the table. This was about the third or fourth drive system I cobbled together. It worked, I stopped guessing.
 
I'm on the same path. Just finished powering z-axis (direct drive, no gears) and am starting on the x-axis. I'm going to follow the design shown here: https://www.hobby-machinist.com/threads/mini-mill-x-power-feed.36948/. I like that the shaft can be slid through the motor drive to implement the clutch. I'm planning to create a hex drive adapter on the end of the lead screw. A socket on the end of the drive shaft will engage/disengage the hex adaptor. Will attach it everything to the end of the table using the two M6 holes outside of the small plate that carries the lead screw. No permanent modifications - it can all be put back to stock quickly if desired.
 
Here is one other approach to a clutch for the x table drive- using a floating gear:


I followed the thread of mrjbinok- because this gear drive is "less wide" than a direct drive with Z crank handle and motor drive shaft face to face.

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The support frame was cut and machined for a nice square fit. Notice that there is a 1/8" lip on the end pieces to make it easy to align for welding.

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Mock up with the support taped together.

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After welding assembly is started.

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Original crank is removed.

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12 volt power supply is mounted to the wall abd motor assembly is trial fit on the mill.


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I decided on a spring loaded momentary ON-OFF-ON rotary switch and picked up a perfect box from Amazon. I wanted the box to mount at an angle so used a couple of cabinet hinges to mount. Later I locked the hinge in this position and used JB Weld to make it somewhat permanent.
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My unit has the DRO monitor right in the way, and its pretty crowded space up there and hard to reach.....

Want sort of same thing on the x drive system, with the motor as close to the table as possible . The floating clutch gear in the utube video seems easy to use, but not sure if plastic gears will hold up...


 
Yes, my z-drive is "wider" but not enough to get in the way of the DRO. I thought direct drive would be a little simpler. I put the switch in a box that sits near the base of the mill so I don't have to reach up/back at all.

I'm planning to direct drive the x-axis as well. The design will be similar to what mrpragmaticlee did on his mini mill power feed. In this case the shaft will slide through the motor drive instead of along the motor drive shaft. The only concern is that the shaft is 4mm square - would like a little more meat. I believe the motor was intended for power seats so if it works there then it ought to drive the table.
 
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