Looking At A B&s 612 Surface Grinder

rwm

Robert
H-M Lifetime Diamond Member
Joined
Mar 25, 2013
Messages
4,606
Hello,
I am looking over a Boyer Schultz 612 surface grinder shortly. I am not familiar with these machines. I would really appreciate some help from someone with experience! What parts typically fail or need to be replaced on these? What else should I be looking for? What would be a deal breaker? It comes with a chuck. Is there an easy way to test holding power? Any other advice appreciated. FYI it will probably not be under power at the time.

Robert
 
Boyar-Schultz are good grinders. It will have a spindle with high precision ball bearings. If they are not good it will likely cost more to fix than the machine is worth. Even doing the work yourself, which can be dicey, the bearings can be quite expensive. $500 or more is not unusual for surface grinder bearings. If the spindle has been modified or changed to a single phase motor, I suggest that you walk away. You can sometimes tell if a spindle is bad by turning it by hand, but cannot tell if it is good without running it and doing some test grinds.

Check the cross feed handle for backlash, an excessive amount indicating wear. See if you can remove the table to inspect the ways, the oiling system, and look for wear, damage, abrasive gunk, and lack of care. It usually lifts right off, only held on by gravity. Inspect the table rollers carefully. If there are dings on the rollers and/or the table from bouncing while transporting the grinder with the table on, you are probably looking at scrap metal. Remove grinder tables for transport.

If it is a permanent magnet chuck, put some parts on it and try to move them. An electromagnetic chuck will need to be powered up to test it.

A surface grinder that is not under power and put through some tests might well be scrap metal or close to it, regardless of what it looks like. The selling price should reflect that. That said, I just finished rehabbing a surface grinder which I bought in not running condition and with a known bad spindle. With the help of the seller, it is now back running well and with relatively little money spent on it. Trusting the seller is often a BIG part of buying an old and not running machine, along with a good inspection of the machine, the shop, and carefully vetting the seller's character as well as is possible. My grinder turned out to be good, and the seller has been wonderful...
 
Thanks for the reply Bob. The machine is at auction so the seller is unknown. Sounds like it is too risky unless it goes for a steal. BTW why should I stay away from a single phase conversion? My understanding is these are driven by a lovejoy coupling to the motor, right?
Robert
 
Single phase motors vibrate and do not hold constant rotational speed in the envelope of one rotation.

Even with a bad spindle, a surface grinder can still be very handy in a shop. Any ripples in finish will probably be in the tenths, and will still work well for tool and cutter grinding. Let's face it, itll be better than a bench grinder.

And depending in the work you do, slight ripples in the surface may be perfectly acceptable. If you're a toolmaker grinding precision tools, probably not.



Sent from my XT1053 using Tapatalk
 
Got it. Thank you! I'll see how it plays out.
Robert
 
Ya know...I'm also wondering, if I can't get new spindle bearings if I could just make a new spindle to fit in the housing. Mark and Bill are doing it from scratch. I could always borrow/steal their design and adapt it.

R
 
Negative Ghostrider...I examined it and it was rough. Probably had shot spindle bearings. Not sure about the wear on the ways. Some sucker bid it up over $500. I feel like these auctions get out of control when internet buyers who have not inspected the machines start bidding. I priced out the bearings alone at $400 on ebay. I will keep looking around. I would spend some cash on a nice one if I can find it.
Robert
 
Back
Top