- Joined
- May 25, 2016
- Messages
- 181
Good day, I need some advice. I have taken apart my 1955 round ram table and saddle to clean out the grease put there by previous owners. What a mess.
While apart, I am curious if I may need to replace the bearings.
The left side of the table, there are two Norma bearings that are 20mm x 47mm x 15.3mm. (not standard 14mm width!) They are shielded on one side only - the two open sides were facing each other. They don't seem to be overly smooth, but after cleaning out some junk, and blowing them out with compressed air, they spin fine, just not "frictionless". Not sure these types of bearings were supposed to spin effortlessly though.
So questions - how do I know if they are OK? They don't seem to have any slop side to side or up and down. I assume these are mainly for the axial load when moving the table (so they may be deep groove bearings?)
Nobody makes direct replacements from what I've learned, so should I put some fresh grease in them and re-use? Or perhaps buy some 6204ZZ bearings and make a spacer for the, so that the overall width matches the originals?
Do I need to worry about the ABEC rating for these, or since they are not for a SPINDLE (just a table), is it not really that critical?
Any advice is welcomed. On a car, it was always easy to know when bearings are shot. Not so easy on a 60 year old Bridgeport, though. (or I just don't know what to check...)
-Tom
While apart, I am curious if I may need to replace the bearings.
The left side of the table, there are two Norma bearings that are 20mm x 47mm x 15.3mm. (not standard 14mm width!) They are shielded on one side only - the two open sides were facing each other. They don't seem to be overly smooth, but after cleaning out some junk, and blowing them out with compressed air, they spin fine, just not "frictionless". Not sure these types of bearings were supposed to spin effortlessly though.
So questions - how do I know if they are OK? They don't seem to have any slop side to side or up and down. I assume these are mainly for the axial load when moving the table (so they may be deep groove bearings?)
Nobody makes direct replacements from what I've learned, so should I put some fresh grease in them and re-use? Or perhaps buy some 6204ZZ bearings and make a spacer for the, so that the overall width matches the originals?
Do I need to worry about the ABEC rating for these, or since they are not for a SPINDLE (just a table), is it not really that critical?
Any advice is welcomed. On a car, it was always easy to know when bearings are shot. Not so easy on a 60 year old Bridgeport, though. (or I just don't know what to check...)
-Tom