New Counter-shaft Bushings

Off the Topic by a bit but.. here goes.
The Atlas 10" Lathes IE: My QCGB-42 uses Needle Bearings on the Counter Shaft.
Is there any reason why I couldn't/shouldn't make a holder part and press in Oillite Bushings as replacements?
These older style needle bearings use the screw cap grease feeders and they basically spray grease over time and the walls.
I'd like to reduce the mess a little - that and my shaft has some seroius scores in it and not having to bore out a new repalcement and thread for the caps would make it a simpler project.
 
Keep in mind that oilite bushings, from what i remember have an RPM limit of around 3000-3500rpm! Other then that i dont see where it would cause any other issues that you dont already currently have so if they end up not being what you wanted you would be no worse off then you currently are and learned something in the process IMHO.
 
Latinrascalrg1 said:
The main reason to Not use motor oil with detergent additives is because of the way they attract and absorb moisture! Basically the amount of detergent additives used is directly correlated to how hygroscopic (water absorbing) the oil will be! This collection of moisture will eventually cause your machine to start corroding and forming sludge in the oil reservoirs and feed system.

With that said, Motor Oil without the additives such as, "STP non detergent motor oil" that is made for 1930s and earlier antique cars can be used in a pinch if needed.
Click to expand...

Thanks. That's interesting, I didn't realize detergent oils absorbed water. I've been using that type of oil not realized what it could do.
 
Oilite is merely a common brand of porous bushings. There are MANY different types, made from different materials, with different porosity, ones that come previously impregnated with any of many different lubricants, oil, wax, grease, Teflon, just to name a few. Every one is designed for a different application -- load, speed, ambient temperature, shaft materials, etc. They are not generic, though many different companies make similar bushings for similar jobs. You really need to know what you are working with, especially with higher speeds, higher loads, higher temperatures, and uncommon shaft materials. There are online data sites from some of the manufacturers, and they are free. Use them!

There are also rules to follow for supplying lubricant to the bushings. Some are simpler than others, depending on the details.

Here is some information for the original:

Oilite - Wikipedia

en.wikipedia.org en.wikipedia.org
which is still available, but just the tip of the iceberg. Most of the ones seen in local stores today are Asian imports, with little or no data on applications, lubrication, load, or anything else.

The right combination of bushing, lube, load, and mounting can make for a bushing that lasts near forever with proper care. Picking an unknown with no idea of how to best use it can often result in early failure.
 
I took another look at the part number on McMaster-Carr, it specifies SAE 30 oil as the lubricant. It had load ratings and temps as well. The bushing spec is 2250lbs at 60rpm. What I don't know is what loads the bushings will see on the lathe. I have to go out and measure the pulleys to figure out the countershaft speed, but the motor is 1750, so I'm guessing the countershaft will be more than 60.
 
yendor said:
Off the Topic by a bit but.. here goes.
The Atlas 10" Lathes IE: My QCGB-42 uses Needle Bearings on the Counter Shaft.
Is there any reason why I couldn't/shouldn't make a holder part and press in Oillite Bushings as replacements?
These older style needle bearings use the screw cap grease feeders and they basically spray grease over time and the walls.
I'd like to reduce the mess a little - that and my shaft has some seroius scores in it and not having to bore out a new repalcement and thread for the caps would make it a simpler project.
Click to expand...
Yendor ,
Do your spindle bearings have grease nipples, cups or screw down grease caps as the lubrication method .

I thought my Sphere ( Atlas specially made for the UK in WWII ) was the only lathe out the Atlas stable that had them
 
In general, things designed to hold oil, cannot be over oiled. So things like the oilite bushings, and chains, I drop in the oil bottle when I get them (assuming they are not for my shelf stock). and if they soak for a day, or forty, they should be ready to go.
 
Round in circles said:
Yendor ,
Do your spindle bearings have grease nipples, cups or screw down grease caps as the lubrication method .

I thought my Sphere ( Atlas specially made for the UK in WWII ) was the only lathe out the Atlas stable that had them
Click to expand...

My countershaft has the Screw Down Grease Filled caps that as you tighten them force grease thru a center hole bored in the shaft to the needle bearings.
The needle bearing holders have FELT Washer in the Collars that hold them centered on the shaft.
The grease eventually gets thrown out from those felt washers and marks a stripe on the walls.

The newer 12" Atlas seem to use an Oillite bearing in place of the needle bearings on the same shaft part.
I'm thinking there shouldn't be any reason why I couldn't make a holder part and press in the olilite bearings and do away with those old style grease caps.

As I mentioned my shaft has some scoring where the needle bearings run.
Not too bad but enough to make me want to replace.
If I go the Oillite bearing route I wouldn't have to thread the ends for the caps, and could elminiate the need to bore a center hole and smaller cross hole in the shaft for the grease supply channel.
 
Although the Atlas 10" countershaft assemblies used separable straight roller bearings (not needle bearings) over their entire production life, the 6" and 12" machines introduced only a few years later always used Oilite bushings. So I see no reason why you couldn't convert your 10" to use them. However, unless you make an externally similar bushing carrier from scratch, you will need to make a steel bushing to press into the outer race with an ID to properly match the bushings (you will also need to drill the outer race and steel busing for an oil cup). I do not think that you are going to find any commercially available sintered bronze bushings with anywhere near the wall thickness required to fit the ID of the races and the OD of the countershaft.

The approximate maximum RPM of the countershaft on the Atlas 10" with a 1725 RPM motor is about 980 RPM. I didn't bother to get out the Machinery's Handbook and look up the correction factor for OD to PD but just assumed it was about 0.30".

And the SAE 20 ND oil or equivalent (ISO 68) oil that you should be using almost everywhere else on the machine will be fine there.
 
yendor said:
Off the Topic by a bit but.. here goes.
The Atlas 10" Lathes IE: My QCGB-42 uses Needle Bearings on the Counter Shaft.
Is there any reason why I couldn't/shouldn't make a holder part and press in Oillite Bushings as replacements?
These older style needle bearings use the screw cap grease feeders and they basically spray grease over time and the walls.
I'd like to reduce the mess a little - that and my shaft has some seroius scores in it and not having to bore out a new repalcement and thread for the caps would make it a simpler project.
Click to expand...
A really nice project is to make new bearing carriers and use pressed in sealed ball bearings, Clean quiet and you should never have to touch them. 291269291270
 
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