Cincinnati 220-8 Repair!

We have bought an old cincinnati 220-8 centerless grinder. I was
wondering if anyone could help me with reconditioning tips. Or if i
could get my hands on a service manual.
I think there is some problem with the hydraulics.
any help would be welcome,thanks,
Sachin
Reply to
Sachin
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Have you checked with Cincinnati?
Reply to
rigger
well, i looked on their website. could not find anyhing! and im in india so.....
Reply to
Sachin
What is the nature of the problem? I've never run a 220-8, but I think they are quite similar to the older #2 or #3 models. The one and only one I observed certainly appeared to be so. I can only assume that you know that the wheel head won't start until the machine has developed hydraulic pressure, which lubricates the Filmatic bearings.
How much rebuild do you intend to do? There's not really all that much to go wrong with centerless grinders, assuming the spindles are in good condition. Their precision generates from the method of application more than anything else.
One thing that is critical is that the dressing heads are capable of providing a straight dress. If you can't profile the wheel properly, you'll have a difficult time getting your parts to spark properly, often leaving ugly feed marks, or not leaving the wheels under their own power. That's not a good scenario. Is the dressing head on the grinding wheel a profile type that runs a template, or does it rely on the ways for form? The type with the template are far superior, allowing for a modified wheel profile.
Keep your eye on ebay------I have seen manuals offered several times. If you are not familiar with a centerless grinder, you should get a manual, or find someone that has run them to instruct you of the principles involved. They're a strange machine that don't necessarily function as you might assume. Knowing the center distance to the wheel from the blade rest is all important to making proper setups. Do you have that information?
Harold
Reply to
Harold and Susan Vordos
Hi, Thanks for the reply. Like you said not much can go wrong with the cincinnati. I got an electrical guy to come and check the machine. All the motors work: - the grinding wheel motor - the regulating wheel motor -and the hydraulics motor
but the regulator wheel actually does not rotate. so could that be because hydraulic pressure is not developing. the motor is working fine. is there any lever to engage it etc... i checked for a manual but one old and torn one is available for 100$! thanks. Sachin
Reply to
Sachin
also im not completly sure what filmatic bearings actually are. any information on that would also help.. thanks sachin
Reply to
Sachin
I don't think the regulating wheel has anything to do with the hydraulics. The only thing I can think of is that the transmission is out of gear. At the bottom of the regulating wheel end do you find one or more levers? They'd be below the feed hand wheel, on the right hand side of the machine, in the base. On the older type machines that's where the transmission for changing the speed of the regulating wheel is located. You might check to see that nothing is out of place.
I've never worked on that end of a centerless, but somehow I get the idea that the regulating wheel is chain driven. Yeah, I know, that sounds crazy, but it operates at a very slow speed, so a chain wouldn't be much of a problem and would be a positive drive, something that is important to successful operation. Please don't take my word for it, it's been years since I last saw a centerless, and even more since I've run one. If it's not, feel free to correct me, and tell me how it's driven. Can you turn the regulating wheel by hand? (Don't try that with the grinding wheel running!)
The filmatic bearings are, to the best of my recollection, split sleeve bearings that operate under hydraulic pressure, which lubricates and also controls the amount of clearance. From that you can deduct that they are pressure sensitive, and it's the main reason that the wheel head doesn't start up immediately. You must have hydraulic pressure for the bearings to function properly. They're reputed to be the most precise method of supporting the spindle. I recall having to adjust them on one machine when I couldn't get it to spark out properly. The wheel dressing attachment wasn't a profile type, and had considerable wear, dressing a slight hollow in the wheel. That's the worst possible condition you could expect if you're trying to get a good finish without feed marks. It likely goes without saying that the machine was quite old, otherwise the dressing head wouldn't have been so worn, so adjusting the filmatics helped, but didn't eliminate the problem. As I recall, the bearings are adjusted under power. The manual addresses that function, but it's highly unlikely one would ever have to mess with them, especially if the machine has low miles.
I'm sorry to say I don't know anyone that owns a centerless any longer, so I'm not much help where a manual is concerned, but if you intend to keep yours and use it regularly, the $100 cost for the tattered one could prove to be a bargain. There's lots of things you need to know about a centerless in order to get the most from it. Are you familiar with their operation?
Harold
Reply to
Harold and Susan Vordos
first of all thanks. yes i am familar with the opration of centerless grinders. we have about 17 machines. and only one of them is hydraulic and none of them is a cincinnati. -so if the grinding wheel is running then is the hydraulics working? a man who came to look at the machine oday said that the hydraulics is totally not functioning. maybe ill need to get the manual afterall. its very difficult to get a man experienced in a cincinnati here. like you said the regulating wheel must be only a gear problem , ill check that. thanks sachin
Reply to
Sachin
You're certainly welcome, but I'm not convinced I'm helping much.
Very good! I was hoping I wasn't talking down to you. That wasn't my intention.
Absolutely, although there could be some fluky thing that prevents the regulating wheel from working. As I said, I've only seen the later machines, I've run only the earlier models, so yours could be different. There is a pressure switch that prevents the wheel from starting until there is proper hydraulic pressure. That I know for sure. You can't walk up to a Cincinnati centerless and hit the start button and get the wheel to run immediately. I don't recall how long it takes for the system to get up to speed before the wheel will start, but it's more than a couple seconds.
I don't agree, not if the grinding wheel runs. That doesn't prevent some portion of it to be buggered, though.
You're certainly welcome, Sachin. Please keep me posted on your progress, and feel free to correct anything I've stated that isn't right. I'm trusting to very rusty memory.
Good luck!
Harold
Reply to
Harold and Susan Vordos
hi, another man came to have a look at the machine. He said that the hydraulics need to be fixed. so getting that done. any tips.... what i should look for when he fixes it. anything else likely to go wrong.
sachin
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Reply to
Sachin
Frankly, I didn't really think it was a hydraulic problem, so I don't have an opinion. I'm not sure I'd know what to look for, or where to look for it at this point. It might be that that particular model is substantially different from the old ones, and my thoughts aren't even in the ball park. One thing for sure, unless he's very good at hydraulics, he could spend considerable time on the machine with no progress. This might be an excellent time to get a manual that provided hydraulic circuitry. Let me know what you discover. Very interesting.
Harold
Reply to
Harold and Susan Vordos

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