I've wanted a used surface grinder for a long time and will be looking at a
35 year old Boyar Schultz model this weekend. Unfortunately I don't know much about surface grinders. How do I tell if the spindle bearings are worn? Assuming I'm able to turn it on, what kind of noises should I be listening for? I imagine a worn spindle will not sound like an ice cube in a garbage disposal. Is there some other way to measure bearing wear?
I've seen several grinders on ebay with teflon ways. Do they come from the factory like this? Or is this an indication that the ball bearing or dovetail ways wore out and were rebuilt with telfon?
I've bought nothing but used machines for my entire shop. The only unit I got took on was a surface grinder. It looked great sitting there, but I couldn't get any decent finish with it at all.
I finally bough another (used) one and gave away this unit.
Hydraulic feed automates the grinding process, indexes the stone across the surface to be ground. Saves tons of time hand feeding. Think of it as a powerfeed for the grinder. Normally an expensive addition to a surface grinder.
My advice, this is one machine you've got to see parts run on it before purchase.
You can hear bad bearings, and of course you can see the marks in the work.
Ball ways cost more than flat ways when the machines were new. If the ways aren't ball ways then take off the table and look closely at the ways. They should look pretty good even in a '60s machine. I don't know about teflon ways .. if your ways are bad then if you grind a longish piece and measure it you will see difference in thickness.
Hydraulic feeds are very desirable indeed. They automate the job of feeding the table.
I'm not certain you *have* to see the machine do work to get a decent deal. But I'm with Karl -- I won't ever buy another one without seeing it work.
A machine with an electromagnetic chuck is much more desirable than one with a plain mag chuck. One with a plain mag chuck is much more desirable than one with no mag chuck. Finally, a machine with coolant capability is more desirable than one without it.
If you ever put on a different mag chuck you have to "grind it in". Google.
Look for a machine being sold by someone who used it, not a machinery vendor. It should be complete, and the spindle and table should travel very smoothly and solidly throughout their whole range. You should get a machine with a chuck and a manual and at least one wheel holder and diamond dresser and hopefully other surface grinder tooling also.
The book, Machine Tool Reconditioning, by Connelly has a chapter devoted to surface grinders. There are relatively simple tests that can be done to determine the condition of any part of a machine.
I'll agree with everything you say but I do take exception to this last sentence.
I deal in machines. I have a reputation to uphold. If you want to say that I cannot speak first hand about the machines that I'm selling, then I'll agree that that is partially true. If you are saying that a dealer will deliberately whitewash a defective tool then I'm going to say that that is very seldom true.
I believe that the vast majority of machine tool dealers will go out of their way to make sure that their customer is happy with what he purchased. If we don't do that, then we won't be in business next year.
With any machine that I sell, I will take care to ensure that the machine is functional. If there are any defects that I find, I will always reveal those to my buyer - always. I don't care if the defect is obvious or latent. I will always tell the buyer about it.
Let me give you an example. Here's a Harig fixture that I sold on eBay:
The broken tooth in the indexing plate turned something that sells in the $500 dollar range into something that sold for $152.50. I would consider that to be a latent defect because you have to disassemble the thing in order to find it.
If you had bought that fixture at a public auction, it is highly unlikely that you would have known about the broken tooth. It is even less likely that you could return it. In all probability, you would simply have to eat the loss.
Now, it's true that you were taking about buying from a user, not from a public auction. However, I'm going to say that a machine that comes from a user is no more likely to be in good condition than the machine that comes from a dealer. Where do you think I get my machines? I get them from users. The reasons that those users are selling them to me is generally the same reasons that they are selling them to other users: they would rather have the cash than the machine.
Now. There are times when I sell something that has a defect about which I am not aware. That is true. I'll even give you an example of such an item that I sold on eBay:
That is a Mitutoyo height gage. It binds as it nears the bottom. Best I can figure, Mitutoyo bored the holes in the base about 0.001" too far apart. The buyer emailed me. I refunded his money and paid to have the item shipped back to me. I didn't catch the problem because I never brought the height gage down below 1". It just never occurred to me that Mitutoyo would screw up like that.
I can give you a very real reason why the stuff that you buy from a dealer is actually better than the stuff that you buy from the user. When I, as a dealer, buy stuff, I check it out as best I can. If I find a significant defect, then 9 times out of 10 I simply don't buy it - at any price. My point is that if you buy from a dealer then you know that a presumably knowledgeable person has looked at it and determined that it is good and useable. You also know that if he's wrong in his assessment of the condition of the machine that he is the one who will eat the error, not you.
And BTW, if anyone is looking for a Boyar Schultz 6-12 here's one:
Nope, that isn't what I'm saying. If you buy from an actual owner who has used the tool, and particularly if you see the machine set up as it has been used, then the owner is in a unique position to show you details about the usage of the machine and answer your questions. I wasn't at all talking about condition or hidden defects.
OK, if you say so. Machine tool dealers also take a machine in that comes with a pile of tooling, then they sell off all the tooling to maximize their profits, and sell the machine stripped to a minimum. Fine for the dealer, bad for a first-time buyer. Hence my caution.
You're the one talking about hidden defects, not me. However, I don't mean to gore your particular ox, George. You may be a fine fellow. You buy from a "user", mark it up, and sell to a new user. Forgive me for saying the new user might want to keep your markup in his/her pocket!
You should move to Seattle. There isn't a single machinery dealer left around here.
I agree with this. I have bought from several dealers and I even returned a machine once. No hassle, full refund. You can operate the machines and play with them. I have even brought in my own stock and grinding wheels to try out surface grinders. No Hassle, no pressure and no inconvience to anyone.
However, I have found that different dealers operate in different modes. Some buy machines and attempt to turn them around without checking them out very much (or at all). They still manage to find a buyer somewhere that is happy with the machine. Others dealers are quite selective in what they buy and sell. These are the ones I like to deal with! Some dealers will even take a wish list. Of course you can not expect bargain prices for service like this either.
I bought a super nice rockwell 11x24 lathe with every accessory you could want from a dealer. Its hard to find a package like this. I got like new Buck Adjust true chucks (3 and 6 jaw), steady rest, follower rest, carriage stop, face plate, driver plate, etc. After using this machine for a while, the bearings got very noisy in the jack shaft. I replaced them, but the dealer compensated me the next time I saw him.
I bought a rockwell horizontial machine from the same dealer a while back. A month after I bought the machine the dealer sent me an #30 erickson collet chuck in the mail for it. Nice guy!
So in my opinion, a good dealer will have contacts I cannot hope to make and can find things I don't have the time to look for. He is also a good source of information. He makes a few bucks and I get nice tools.
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