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New Stones... Need advice


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So I scored some Stones and a base to go with it at a swap meet recently.   


The Stones are big. The Smallest one is 12 inches in diameter.   All in seemingly good condition.

Here is the base, after paint and clean up.


The base is cast iron, and the bearing's appear to be poured with I dunno what.   The motor (not pictured) mounts on top and has a drive gear that turns the big gear.   960 rpm motor, old,  Herman or maybe Sherman Motor company,  still have to clean it up.   The base was painted Bright Red, which I just assume is lead based, since it's so bright.  No idea how old it is.   I opted to just paint over it as opposed to trying to clean it up and make my property even more toxic than it already is.

The drive gear was cracked and damaged (explains the noise when the guy turned it on), which I saw after I got it all apart.   I don't know what sort of material it is made up between the brass,  either a dense or compressed wood, or some sort of old plastic, or something more toxic. I dunno.  It appeared that it could be taken apart since there are 4 pins from the top side,  but I could not get them out.  So I opted to attempt to fix it with Epoxy.   I first JB Welded the whole gear using the JB Stick variety.   Then I carefully hand cut the excess out using the brass top and bottom gears as a guide.   Glutton for punishment I guess.   Since the JB Stick is rather brittle,  I finished it off with a good brushed on coat of G-Flex.   Hopefully that should hold ?  Maybe? Will have to see.  I did not file after the final epoxy since I figured the gear should wear down to true after a while once running.



Still some work to do to get it back up and running.     A few questions for anyone who may know.   There are no markings on the base.  Has anyone ever seen anything like this, have a Company Name, or have any idea how old it may be ?   I think maybe 70's or older.   Google proved fruitless.   

Second, has anyone ever seen brass fittings like this one ?   Logic tells me it is for oil, but seems to me grease would be better.  The bearing's seem solid and not very worn, but I think an oil would just seep out the sides.  I pulled some gunk out of the two brass fittings, which was dark and gunky, made me think grease, but could also be some sort of cloth for oil.  I don't know.   Should I just go with grease and change out the fittings for zirc's ?



The big stone was on the thing when I bought it,  and it didn't explode when it was turned on.  Good sign.    Are these kind of stone's safe to use with water coolant, is it even a good idea ?  Hard to tell, but I'd say the thing spun at 100 - 200 rpm.

Still have work to do.  Seems the original motor mount is not there as it's attached to some plywood that blocks the grease/oil fittings, so I'll either use it as is or make something up,  plus I need to make a tool to get at the oil spot's for the motor.   The bigger two stones seem like they are sandstone, but I don't know.   Is there anything in particular I should know about using these kind of stones, I've never had access to such before.    Also concerns about the smaller stone.     I believe they used to use Carborundum or whatever it's called back in the day,  which was awesome, but also toxic/cancerous if I recall.   Should I be worried ? 

If all works well, I have a couple other stones I'd like to use on this thing once I figure how to mount them...

Any help/advice is appreciated.


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It sounds like you're being pretty cautious about the stones, which I'm glad to hear. I can't find the version posted on this forum at the time, but Sam Salvati's experience with stones like that has always stuck in my head, and I've used it as a cautionary tale a few times: https://www.bladeforums.com/threads/i-almost-died-today-safety-with-old-wheel-grinders.682698/

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1 hour ago, Stuart Samuel said:

It sounds like you're being pretty cautious about the stones

Yeah, I like tools that work For me not On Me.  I've read about Sam's experiences, and it's always stuck in my mind.   It's why I stood well back when the guy turned it on.  Fortunately, nothing exploded, and the wheel speed seemed right.  Not too fast.  I can't really tell if the larger wheels are natural sandstone or not, but if they came with the machine, I think not.  Just an assumption though, and not one I'm counting on.    That's why I'm looking for more information on the machine.  At least a name or year range would help identify it.  Then maybe I can learn more about it.    unless some guy built it in his garage, lol.

 I'm hoping this one will work well for grinding knives.      I have an old wheel I found out in the desert, I think it's an engine surfacing stone from a mill of some sort.  Was at an old abandoned mechanic shop.   Sat out in the desert for like 20 years.  Not sure if it's safe.   May try to mount it after I test out the stones that came with the machine.   Also got another stone I found in an abandoned semi-trailer,  brand new, but I think it was for a pedal wheel.    Used to do demo work (the sledge kind, not the boom kind).  Find some cool stuff sometimes.

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Yep the Sam story could have been tragic, he got lucky!!! I would do a little re-search before I mechanized these stones. They were never built for high RPM's! I would be very cautious with these stones at higher RPM!! Do any of these stones have markings on them as to reference the maker! Every time I hear of someone trying this I think of Sam and the pictures he posted of the exploded stone!! Had he not rolled out of the way he might not be around now!! The pictures would have been taken by the coroner! 

C Craft Customs ~~~ With every custom knife I build I try to accomplish three things. I want that knife to look so good you just have to pick it up, feel so good in your hand you can't wait to try it, and once you use it, you never want to put it down ! If I capture those three factors in each knife I build, I am assured the knife will become a piece that is used and treasured by its owner! ~~~ C Craft

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I'm thinking 1915-1930 for an age range.  Those brass thingies are oilers, and like most old machinery the bearings are not sealed and are meant to leak to stay flushed clean of goo.  Don't replace them with grease zerks, and use something like bar and chain oil in an oil can.  It is possible there were felt plugs between the oilers and the bearings to slow down the drip.  The bearings are babbit metal, aka lead/tin with a little antimony.  Keep them oiled and they last nearly forever.  Take care of the motor, slow-speed motors are rare and expensive beasties.  And nice job fixing the gear!  Stacked leather would be my guess.

I imagine you could run the stones wet.  The only advice I have heard on that is not to leave them partially soaking in a tub.  Either completely soaked or just use a drip.  Neat old machine!  As long as you don't run it faster than intended it should work well.

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20 hours ago, Alan Longmire said:

I'm thinking 1915-1930 for an age range. 

Wow,  I didn't think it was that old at all.  It must have been repainted at some point in it's life.   The stones themselves must have not ever been used much if at all, since they look in almost new condition, minus a few dents/chips on the far corners.  Still haven't found anything that resembles it on google, but from what I have seen, it looks like many of those old grinders used a shallow water pan of sorts.  I'l try something like that and keep it removable so it doesn't stay soaking, or figure some sort of drip system as you suggest.   Babbit Bearings I've heard of before, never heard of antimony,  learn something new everyday...  Makes sense on the oiler's.  They gunk I pulled out of them did look kind of stringy,  guess I'll have to replace the felt in there if it leaks too fast.    I haven't had a chance to test the gear out yet,  but the paint/epoxy is all dry, and all I have left to do then is get the motor oiled and mounted and the thing put back together.    The motor is at 960 rpm, and from what I've seen at the initial run, it is plenty fast with the gear reduction, so I have no plans at all on increasing the speed. I've been too chicken to pry the hub out of the big stone for fear of cracking the stone, so I'll have to build a couple more for the other stones.   Excited to see this thing running...

Thanks for the Info Alan! :)


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6 hours ago, Bruno said:

and keep it removable so it doesn't stay soaking

Just a thought, but it may be easier to have the pan drainable rather than removable.  Just throwing out another option to consider.  Whatever you do, keep this thread updated!  

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Drainable sounds good!  As for the synthetic stone, Carborundum is a brand name, the actual abrasive is usually aluminum oxide or crushed garnets.  I had not heard these older wheels were toxic, but I guess if the binder contains asbestos (which is entirely possible, I work for a state highway department and you wouldn't believe the places you find that stuff) it wouldn't be a good idea to breathe the dust if used dry.

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