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View Full Version : SAMAND surface grinder spindle bearing pre-load



brozier
10-14-2011, 06:50 AM
Hi Folks,

I've just bought a small footprint surface grinder from a neighbour it was made by "SAMAND" in the UK. Anyone have any information on them?

The spindle had some slop in it which I've traced to a missing circlip - it meant no pre-load on the bearings.

I've ordered a circlip but was wondering how much pre-load the bearings will need? How do you determing this? Do you take up the slack and add a thin shim? How thick would the shim be?

The currently fitted bearings are 6205Z which a re light duty Single-Row Deep Groove Ball Bearings there is is one bearing at each end of the spindle. I'm not sure if these are original as they are shielded so I don't see how any oil could get to them from the central oiling point....

Is it worth me getting "better" bearings - they seem to be in good condition?

Some one has added a thin cardboard shim on one side of the bearing - would that be to allow expansion?

It currently has a single phase motor - I could swap it for a three phase with inverter is this worth doing?

Thanks
Bryan

willmac
10-14-2011, 07:48 AM
I'm not familiar with Samand surface grinders, but I have seen their tool grinders and pedestal grinders.

I would be quite surprised if the 6205Z bearings are the original type. I wouldn't think that these would be suitable for a surface grinder (but they might be OK for a simple pedestal grinder). An angular contact bearing is more likely for a surface grinder and these would have some degree of preload, either built in to the bearing arrangement , via a spring loaded collar or perhaps an adjustable screwed collar. A cardboard shim is definitely not what you need.

It might help to answer your questions if you could provide a photo of the surface grinder.