Rockwell Toolmaker Grinder Query

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A friend is offering me one of 2 Rockwell 24-105 Toolmaker Grinders that are in need of work. He has 2 of these machines he got along with some other machine tools, and they both need some work. Light surface rust on most bare metal, bushings worn/missing on the pinion shafts. Tables move but are stiff. Wrong motor on one with cog belt drive instead of 2 step pulleys, and missing belt guard and motor cover. Spindles on both seem to have oil in the reservoirs and turn freely. My quandary is that I don't really need another project, these are pretty big and heavy, I'm running out of shop space, and if I need parts, what are my chances of finding them. I have bench grinders and disk & belt sanders but no precision grinding capability yet. As a home shop machinist, (9 x 36 mill, 10 x 24 lathe, both old US iron) I'm loath to turn down tools, but how much will I use one of these?
How difficult are they to rebuild? Can I change to a single phase motor without compromising the attainable surface finish too much? Do I need to invest in a bunch of different wheels, or is there something that will work for 90% of my likely needs? Is there anything in particular I should check to make sure that either is a good candidate for restoration?

Thanks for any guidance,

[rkepler]

I'm loath to turn down tools, but how much will I use one of these?

How often do you need to borrow someone else's grinder?

How difficult are they to rebuild?

Not too hard, there's not a lot of real precision parts involved.

Can I change to a single phase motor without compromising the attainable surface finish too much?

Most were supplied with a single phase motor, make sure that yours are not. The original motor and sheave system was balanced, so that's a consideration.

Do I need to invest in a bunch of different wheels, or is there something that will work for 90% of my likely needs?

You will need 2-3 different wheels at the minimum, if you grind a lot of different hardness materials you'll need more. Wheels are cheap, get good ones.

Is there anything in particular I should check to make sure that either is a good candidate for restoration?

You might check to see if one has better table travel than the other, most everything else is pretty easy to fix.

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Thanks for the help, very concise and to the point! I'm pretty sure that they are both currently 3 phase, but I have access to a dynamic balancer if I need to balance a different motor.

[crrmeyer]

A friend is offering me one of 2 Rockwell 24-105 Toolmaker Grinders that are in need of work... and if I need parts, what are my chances of finding them?

Parts are about impossible to find for them. On the positive side, if you get them and decide to part them out, the parts sell for big $$$ on ebay because they are so hard to find.

[PeteM]

These are pretty versatile -- decent for tool sharpening and semi-OK for surface grinding.

Get the one with the original motor and pulley. The motor and pulley have been balanced and it makes a difference in how smoothly they grind. Run it with a cheap VFD if you have to IMO, rather than balancing a new motor.

The ways on these are easy to scrape. The bushings are easy to replace -- just buy some brass bearing stock and turn it to fit. If the spindle bearings are good and the main castings are in place, there's not much you can't make and replace yourself.

Once you have a surface grinder, you may be pleasantly surprised how many uses you find for it.