MILLTRONICS PARTNER III CNC Knee Mill

Hello all, can someone help me figure this out, picked up an old CNC knee mill, Milltronics partner 3 with centurion IV control. Well I have made some progress in getting it running in its original configuration, ( Don't Ask!) Anyway machine is missing the Table Extensions. What i am doing is seeing there is no dog for the X axis limit switches well there is one on left side of table but not on right side.


Could someone please post a picture of the X limit switch dogs so i can make something up? I do not see anything that was previously there so all i can think that it was on the table extensions.

Thank you kindly!

That is if anyone still has one of these in their shop?

Thanks again!

Look for a threaded hole in the bottom of the table and put a socket head cap screw of the correct length into it. That's one way Milltronics has activated limit switches.

Mine might be slightly different as it's a slightly newer machine. But I have a centrally mounted two plunger limit switch and then one ramp on the left side, and two ramps on the right, one is for over travel and one is for homing. I'll try to post a picture...

For what it's worth, here is a picture of a Partner IV. You can see the X axis trip ramps on the front of the table (not the extensions), a few inches in from the ends. This is probably the same arrangement as Brian is describing.

That's the same as mine, you have a better picture. You know, Tony, if you posted pictures of yours and said "where do the limit switch dogs go?" you might have a lot better luck. Not many are familiar with every nuance and difference between the old Milltronics machines. These were basically retrofits by Milltronics of their controls onto imported iron, and not all of that iron was the same. I haves seen at least two or three different brands of machines that they used, although most of the differences have been in the headstock area, so I suspect your axis dogs and limit switches are fairly similar.

Thanks guys, here is a couple pics of the switches this mill is different from yours, the switches are on the back side of the table, any ideas?

Well, that picture definitely isn't like mine, or any of the other knee mill versions I have seen. It appears you have two limit switches, but I only see one trip dog and no other dogs. You should be able to pull up your diagnostics page, find the X home and using your finger, trip the plunger closest to the table. If that changes the screen from 0 to 1, then I would think that is your homing switch. Then if the plunger furthest from the table, that has no dogs to hit, if you trigger that it should kill the X axis servo and throw you into e-stop. If that's the case, then I would suspect the dogs that line up with that portion of the limit switch were attached to the table extensions.

With no power to the servos, hand crank the table over and see if the edge of the table passes over the centered limit switch before you get to the end of the stroke. That will tell you if the dogs lived outboard of the table.

Brian,

My thoughts exactly, Too bad your saying this machine is uncommon. good luck finding the original table extensions and dogs. I guess i can make something up to bolt in place of the originals. I believe these were all castings from Taiwan cause i can't find parts anywhere. Not even Milltronics has parts. This machine is one step closer to the scrap yard.

Just because I haven't seen one, doesn't mean it's not common. Have you googled "Milltronics Partner III" and looked at all the pictures, I just came up with hundreds. The cast tables are nothing special, and on mine have no attachments for ramps/dogs. I'm a bit surprised that something as simple as dogs is making the machine "one step closer to the scrap yard".... figure out if the limit switches work as I said, and come up with something to trip them.... kind of a no brainer in my book.

Brian said:

Just because I haven't seen one, doesn't mean it's not common. Have you googled "Milltronics Partner III" and looked at all the pictures, I just came up with hundreds. The cast tables are nothing special, and on mine have no attachments for ramps/dogs. I'm a bit surprised that something as simple as dogs is making the machine "one step closer to the scrap yard".... figure out if the limit switches work as I said, and come up with something to trip them.... kind of a no brainer in my book.

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Thanks, that was the first thing i did was check the limit switches as i have been trying to bring this machine back from the dead=Zombie! what i meant is parts parts parts..If i need something say wipers, gibs, or something to do with the machine (not electronics whole other world!=Zombie!) good luck! This machine in its present condition is just about not worth even the retrofit, Its been USED=Zombie! Point is that i appreciate your info and help I grabbed this machine in hopes of something simple being wrong with it, its one thing after the other! Not supported by Milltronics. And has seen some chips in its life, So is the zombie ready for the grave? Almost its just not worth the time or $ Maybe a quality machine like a Lagun, now were talking worth the effort to retrofit. Thanks again for the help! Boat anchors+Zombies=

is it possible the overlimit for the side without a trip is software controlled?

Mine has software and hard limits, so that's entirely possible that this machine uses soft limits. My only question on that is, why have two limit switches then? It wouldn't seem normal for them to have a double plunger limit switch and then not have dogs that activate one of the plungers.

Tony, you can't really expect to get parts and service on a machine from the 1980's.... there might be a few brands that support their equipment from way back then, but it's rare. You do what I did, search out the companies that make the way wipers... found them. The gibs? They don't need to be replaced, maybe cleaned, but those are fit specifically to each machine and axis. Parts are out there, you have to be creative as to where to look, or be willing to make them yourself. I made a new cover over my Z axis drive belt, rebuilt the motherboard in the computer, added memory capacity, made way covers out of shower pan liner plastic, added mist coolant with a home made MQL unit. the list is endless, you just have to be creative and willing to spend some time on it.

Now, if you wanted something to turn on and make parts today, then you should have spent some money and bought a newer, running machine... but that is/was your choice.