Mattison 12X36 Horizontal Surface Grinder cross feed problem

I have an old humpback I bought last year that is giving me fits. If I set the cross feed to a low feed it will work for several table oscillations and then the cross feed valve or switch will stick, causing it to in effect go into dress mode and rapid across the part. If I turn the cross feed amount up it is less likely to happen. Anyone have any info on where to start looking? Otherwise it runs very well, grinds very well.

Thanks

Ok- so on the humpbacks a lot of the crossfeed items are mechanical. But then it works with the valves on the hydraulic unit.

Can you confirm no broken linkage ect?

These old machines are tough to work on and spare parts are pretty much obsolete.

I had one humpback years ago but now all square columns.

If you get desperate DM me and I will send you the name of an ex mattison guy who could help.

KevinV_MEI said:

I have an old humpback I bought last year that is giving me fits. If I set the cross feed to a low feed it will work for several table oscillations and then the cross feed valve or switch will stick, causing it to in effect go into dress mode and rapid across the part. If I turn the cross feed amount up it is less likely to happen. Anyone have any info on where to start looking? Otherwise it runs very well, grinds very well.

Thanks

Click to expand...

I gave up on the mechanical valving on mine. You may find a simple fix though. Ours used to have on shift rod stick on a regular basis. It had worn and was rubbing on one of the lines. Every once and a while it would just stop!
We are using a small hydraulic pump regulated down to about 75 psig. The pump turns on from the switch in the column and will then only operate when in auto mode. We then used 2 micro switches a servo valve and flow re-stricter to control the cross feed.
So far its bee working great.
Good Luck1
Ed

Thanks for the quick replies. I'll look into the linkage issue.

I ran into a different problem, the main lube pump stopped working(no pressure). If I prime it it will maintain pressure but sitting overnight it will loose it's prime and not build pressure.

I thought the filter might be clogged so I disassembled it, cleaned it, etc, good flow there.

Tank is full 1" above pick up hole

I tore the pump down, cleaned and reassembled it. The shaft is slightly worn, and I think it had been disassembled in the past and not put back together properly, seems like the packing is missing on the input shaft side. It did work before though.

Anyone have a B and S no 1 pump laying around? Rebuild kit? Replacement alternative?

To close this out it was the arm that is tripped by the table dog at each end of the stroke sticking ever so slightly and keeping the switch engaged keeping the valve open, causing the head to feed at inappropriate times. Also the lube pump is easily rebuildable.

A five-year update! Better late than never, it's appreciated.

If you get a minute, post some pics of the machine?