Retrofitting a 1986 Maho MH400E

That is really frustrating for wait for those balls to arrive, only for them to be junk. Maybe you should post a request for help finding either a reliable ball suppier or a Ball screw refurbisher on Practical Machininist
www.practicalmachinist.com/vb/search.php?searchid=13618306

or if you like I can ask on the German language machining forum...
forum.zerspanungsbude.net/
for a recommendation?
Mark

Hi, yes plz ask in that site.
John

Do you have any bicycle repair shop near you? Try there ! I neded some 6.320mm ones some 6 years ago and having no way of getting them, went to such a shop. Got 200 of them for 10 euro, set them up and they are still happily working! I am aware that i lucked out on that, but worth a try, they had only 4 sizes of them.

From the Zersannungsbude...

This place has bearing balls:
www.kugel-winnie.de/epages/62136757.sf/d...Path=/Shops/62136757
It was recommended that you contact them which the exact size you need, which may be something they havent listed in the web shop.

There was a short discusion about replacing every second ball, and recommendation that the balls are normally toleranced G5.

The recommendation came for this overhaul facility:
www.eisenmann-hommes.de/reparaturen-%C3%BCberholungen/
Mark

Thank you Mark, I will contact them to order the right size I need. The replacement of every second ball with one smaller (spacer) helps the balls not to rub with its other. But with halve the balls make contact with ballscrew and nut, the forces on every contact point during accelerations and decelerations is now doubled. I don’t have enough knowledge on the subject to decide such a change in the ballscrew. I am open to suggestions and opinions on the subject.
Tommy thank you for the suggestion. The problem is not to find the balls, the problem is to find ball with the right tolerances (or better) and size with the originals. I have find balls from local stores, but they sound and feel terrible in the ballscrew.

Didn't get anything done on the MAHO last week, but yesterday I reinstalled the ribbon cables.

I took another shot a troubleshooting the "machine on" relay not latching on. I'd already isolated the problem to the MAHO relay panel. I'd been overthinking it, wondering if there was some logic wired into the panel.

I did basic continuity checks according to the wiring diagram. Pulled the 19K1 relay and the manual brake release switch. The problem is in the row of plug in screw connections along the bottom of the MAHO relay board. Resocketing the middle terminal plug closed the circuit.




Turned everything on and sure enough, the control latches on. Woohoo, as I can now move on to getting some motion.

I'd noticed an intermittent contact problem alone that row of plug in screw connections before. The 7i84, and 7i77 pick up 24V and 0v from there, and I have a couple of times where LinuxCNC errored out doing start as they were not getting power. If the the pins in the plugs are worn out, It will be easy enough to buy replacement connectors, and just use the plugs.

Out of batteries on the laptop, but I'll add photos tomorrow in case someone else has the same problem.
Mark