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Robot surface grinder Manual and Power feed issues

jmjones

Plastic
Joined
Oct 30, 2014
I have a Robot Machine Co surface grinder that looks like a Brown and Sharp #2. The power table feed is not engaging and it is fairly difficult to move the table manually. Its not locked up or anything, but the longitudinal axis takes significantly more effort than the cross feed to move. Is this normal? I would like to get the power feed going but if not at least have the table move easier if that is possible. Thanks for your help.
 
If the table runs on balls or rollers,they may be a mass of rust.......squirt some oil up under the table,and get a little USB camera and see if you can see whats going............if its just plain cast iron,oil,and fill any oil troughs exposed by running the table as far either way.....Dont know the machine,but the table may just lift off.
 
Yeah I'd pull the table and see what's going on. You may need to disconnect a few things underneath to do that, depending on the specific machine.
 
I think that is an old-school iron oil/way machine. If so one of the oil pots may be dry.
fill them with real way oil..not 30 Wt lubricating oil.
If the oil rollers are missing you might use hardwood dowels. I have seen people use ping pong balls.
(I don't like the ping pong method)
Pulling the table is a good idea.
 
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I found a photo of the Robot 618 SG, and yes it is an old-school grinder.
This one has problems with the auto-feed, likely because a way is dry, so making a belt slip.
Many of these old grinders can be scraped to new condition..and then last another 20 years or more.
 
I pulled the table off and the ways were dry also there was grease in zirks for the ways. There was a lot of sludge that I cleaned up and filled the zirks with way oil. I didnt have time today to put it back together, but does this sound like I am on the right track? Anything else I should do while the table is off? thanks for all the help so far


Thanks

John
 
Op Q: (Anything else I should do while the table is off? thanks for all the help so far)

Super flat ways will not hold oil on the surface but squeeze it off. Flaking or shallow oil grooves helps keep the ways wet with oil. Good to study this for a time so as to do it right. Oil pots need some kind of roller to rub oil on the ways.

Take notice of the long travel drive gear, it should have a little slop/free play so the table is only riding on the ways.
Put a strip of tape at the gap of long Table to the carriage so it is stuck to the table and free to the carriage. A wipe of oil on the carriage makes not-stick happen there. this the gap that allows grits to get in the works.

*Don't grind the chuck until you have the correct wheel and procedure down pat.

For fussy work use that area closest to where you stand..that is the least used.

The machine casting is likely full of filler, so sanding can be better than stripping.(wear a mask when sanding old paint).

Never air hose blow the machine or even parts when close to the machine. The air hose should not even be in the same room.

Good to make a wallboard for wheels, with it having a dist cover, wheels on a 1" wood dowel.

Use Long-Cross and Vertical or Down for movements/travels not xyz.
XYZ is for CNC machines not manuals.

* And lastly(for now) It is Very important to make your thread title better for a future search.
"Surface Grinder Manual and Power feed issues" this whole thread is just Hen,s Chatter if nobody can find it in a search..And your location should be added to your stats.

Could be that the ways drag is making a belt slip and messing up your power feeds.
 
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QT Op: (also there was grease in zirks for the ways.)

This is the common hack-method to make a grinder table move. It affects the accuracy so not a very good method, grease it too thick to lay flat/evenly to .001 or .0002
 
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QT Op: (also there was grease in zirks for the ways.)

This is the common hack-method to make a grinder table move. It affects the accuracy so not a very good method, grease it too thick to lay flat/evenly to .001 or .0002

Right, and the high viscosity of grease means the table will erratically float on the film of lubricant - with differing amounts of lift at different speeds. Not good. Get it changed back to oil if the previous owner was using grease. I would start by inspecting and understanding how your lubrication system functions and make sure it's working correctly and reliably.

After that, does this machine use hydraulics for table motion or is it purely mechanical?
 
Oh ..and don't wire brush the numbers on the handwheels.
Use a fine flat file to just take off a bug, then very fine abrasive paper with a stiff backing...or not using the abrasive paper.

You want the number edges to be sharp and crisp/not have rounded edges.
 
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I think that is a rare grinder so a few photos would be appreciated.
Good to Jog start any high-speed spindle, run it up to about 1/4 to 1/2 speed let down, and then fire up. I knew grinder hands who would spin once by hand..and then jog start. If you ever lose a spindle because of a cold start, then you become very careful...To close the door after the horses are out of the barn
Buck
 
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I have a Robot S/G with the same problem. I haven't really looked into it yet but I will have to do something about it as it really gives the muscles in the left arm a hard time after an hour or so of use.
 
Here is an old PM thread on way flaking. I don't know much about it but have put on half-moons on some too flat ways. They are just half-moon looking detents that you try to make look nice and a pattern that does not cause excess wear in any straight line. They tend to hold some oil on the ways.
That above is the PM thread, not Me as I have not gone to one of Richards's scraping cases...perhaps I will someday.

Here is a you tube, My old scraper is an on the shoulder and bump, but I don't know where my blade is..darn.. I hope I can find it,
 
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Re: XYZ is for CNC machines not for manuals. long, cross, and down for manuals.
The definition for XYZ is odd for grinders because of the way the spindle is in relation to the table and how things travel.
Even for CNC grinders, there was one outfit (perhaps more) that had XYZ different than what is most common.
A CNC grinder shop needs to be sure that a new different make grinder has XYZ the same as the ones in house..and be sure a program has XYZ the way they expect it to be..A darn shame that I can't remember what machine had it different...I don't know if they still have it different,.
 
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Bruce (ballen) has a thread where he does some flaking on the ways of his grinder. I did mine also last year but I didn't take any pictures. I'll see if I can find his thread.
 
Here you go:

 








 
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