Maximat7 restore/refurb

B

bfk

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The high school robotics team where I’m a mentor was gifted a Maximat7 by the local University. It’s in mostly good, but somewhat neglected shape. We were told that it was all working when last used. But we don’t really know when that was.

Liberal application of contact cleaner got the switches working. Some 3D printed parts means we don’t have to use pliers and hammers to operate the switches.

The two plastic gears in the train to drive the lead screw were in kit form, so I made new ones from Delrin. (First gears I ever made. You Hoo for my Sherline!) Now the gears will run in forward or reverse. Sadly, the lead screw doesn’t move. I suspect the pin that holds the lead screw to the last gear has broken. Possibly because any grease in the system has long since petrified. Does anyone know what that pin is supposed to be made of? The parts list I found online describes it as a bushing, but it clearly isn’t. I don’t want to replace something sacrificial with something too strong.

When I take it apart to find the broken part I’ll also clean out the ancient grease. What kind of grease should I replace it with? Also there are multiple grease points described in the manual, I assume they all take the same type of grease. Is there any special tool required to squirt the grease in, or just any old cheapie from Hazard Fraught? Perhaps some special tip?

I wish I had more time to play with it, but there’s a local competition in three weeks and the big worldwide competition starts in January. Still, we survived 10 years without a lathe, so one more won’t kill us. I already had one of the girls using it to centre drill and tap a shaft, so we’re ahead of the game already.

Thanks,
Brian
 
One of our guys, @Rockytime, has a Maximat 7 and hopefully he will join in. I am not sure about the Maximat 7 but the lead screw shear pin on a Super 11 is made from aluminum.

My lathe calls for Mobilgrease Special or the equivalent. You can buy it in tubes from Amazon. You'll want to use the push type grease gun with the rounded tip, like this one: https://www.amazon.com/Lumax-LX-117...pID=31epQ4kcyiL&preST=_SY300_QL70_&dpSrc=srch

You might want to join the Emco Larger Lathes Yahoo group. Their files and members will have much more detailed information.
 
mikey said:
One of our guys, @Rockytime, has a Maximat 7 and hopefully he will join in. I am not sure about the Maximat 7 but the lead screw shear pin on a Super 11 is made from aluminum.

My lathe calls for Mobilgrease Special or the equivalent. You can buy it in tubes from Amazon. You'll want to use the push type grease gun with the rounded tip, like this one: https://www.amazon.com/Lumax-LX-117...pID=31epQ4kcyiL&preST=_SY300_QL70_&dpSrc=srch

You might want to join the Emco Larger Lathes Yahoo group. Their files and members will have much more detailed information.
Click to expand...

I tried to join that group, but was refused with no reason stated. Didn't amuse me very much.

Thanks for the Amazon link, that goes on the shopping list.
 
Check inside the headstock when you can, there are shifter forks that can get messed up, one weak link of an otherwise pretty good machine.
Does yours have the 4 speed milling head also?
Mark S.
 
The innards of the headstock are fine. It's a bit fiddly to get the gears into place, but I think part of that is the levers slipping on the shafts.
We do have the milling head. I suspect the machine was mostly used as a drill press for the last several years. Or decades.
We also have set of collets, some still wrapped, with the draw bar, but I don't see any kind of nut to protect the spindle threads, as I see on the parts list.
The tub o' parts also included a bunch of stuff that is yet to be identified, but I believe some are small parts for the electron microscope that the department retired a couple of decades ago.
It's an adventure. With added teenagers!
 
Progress. Got the lathe almost fully greased after removing grease that had been there since Vanilla Ice was big time. The part that changes feed speeds was very time consuming to clean, but that just makes the victory all the sweeter. Most of the grease fittings needed some quality time in increasingly powerful solvents to loosen the ball bearings.
The only fitting I have yet to conquer is the one on the carriage. It is caked solid. I'm reluctant to take the carriage apart since, I assume, its alignment is critical. From what I see in the manual, this fitting greases the leadscrew for the cross slide, so I poked a greasy finger in from underneath and got some on the screw, which did move more freely.
Am I being too cowardly about taking it apart? It seems odd that the fitting is several inches away from the leadscrew, and a little lower down. I fear that whatever path the grease is supposed to follow is one long line of rock hard former grease.
 
Take it apart, bfk. Emco lathes are simple to work with and there is nothing that requires force. Most everything will self-align.
 
mikey said:
Take it apart, bfk. Emco lathes are simple to work with and there is nothing that requires force. Most everything will self-align.
Click to expand...
Well, mikey, you kind of pushed me past my comfort zone. Thanks. Took it apart removed lots of gunk, cleaned it, greased it, and even got it back together. Amazing how much smoother it is now. And I have a slightly larger comfort zone.
Turns out the grease nipple on the carriage doesn't lubricate the cross-slide screw, just the shafts around the carriage handwheel. There doesn't seem to be any way to lubricate the cross slide leadscrew at all. That seems odd, but there is nothing in the diagram that shows another grease or oil point, and I don't see any.
Ever onward!
 
The larger lathes have a grease point but it really isn't used often. Grease the cross slide leadscrew well and it will probably be fine for the next 5 years or more. Nothing on an Emco lathe is a major challenge - you got this!
 
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