Question about bronze bearings

[Makintrax73]

This seems like a dumb question

I have a "new" 1950s Logan 9B. The manual says put a drop of machine oil in the holes in the countershaft bearing supports. Ok fine.

BUT...I took this thing apart. There are NO through holes going into the shaft. These oil holes seem to hit the back of a solid bearing and end.

So I know there is such a thing as sintered bronze which liquid flows through. But I thought bearing bronze was solid? Did someone change the bearings and forget the through holes at some point? Or is the bearing material porous enough to flow oil to the shaft surface?

 

[Al 1]

yep, oil is supposed to go through that type of bronze.

 

[Makintrax73]

OK, thanks!

 

[benmychree]

Double yep, this sort of lube is common in low stress installations using porous bronze bearings.

 

[Aukai]

I learned something, so it wasn't a dumb question. Everyone should ask their questions, there are enough members, and guests, someone will learn something.

 

[extropic]

This seems like a dumb question

I have a "new" 1950s Logan 9B. The manual says put a drop of machine oil in the holes in the countershaft bearing supports. Ok fine.

BUT...I took this thing apart. There are NO through holes going into the shaft. These oil holes seem to hit the back of a solid bearing and end.

So I know there is such a thing as sintered bronze which liquid flows through. But I thought bearing bronze was solid? Did someone change the bearings and forget the through holes at some point? Or is the bearing material porous enough to flow oil to the shaft surface?

When you say "new", do you mean new to you (previously owned by someone else)?

My point is, unless you have owned the lathe since new and/or are certain that the bearings in question are OEM bearings, we don't know what type of bearings they are now.

I would want to make sure that the shaft is well lubricated. Oillite type (sintered, porous, oil impregnated) bearings are pretty easy to visually differentiate from solid bronze materials. My recommendation is to figure out what type of bearing material you're working with.

 

[Ulma Doctor]

a sure test is if the oil soaks into the holes, by the next day
if you still have oil pooled up like in the pictures, you may have solid bronze bushings
provision may dictate weep holes being drilled into the solid bushings

 

[SLK001]

If the shaft turns freely, then you have to deduce that your bearings are indeed of the sintered type. UD has a point in that if the oil seeps into the hole, the bearings are not solid bronze.

 

[Makintrax73]

When you say "new", do you mean new to you (previously owned by someone else)?

My point is, unless you have owned the lathe since new and/or are certain that the bearings in question are OEM bearings, we don't know what type of bearings they are now.

I would want to make sure that the shaft is well lubricated. Oillite type (sintered, porous, oil impregnated) bearings are pretty easy to visually differentiate from solid bronze materials. My recommendation is to figure out what type of bearing material you're working with.

New to me. I didn't look that closely to be honest. I'll have to do some more investigating. They looked like solid bronze at a glance.

I'll put some in the weep holes and see if it soaks in or not.

Thanks.

Edit: I slid the shaft over and took a picture

 

[FOMOGO]

Not seeing any exccessive wear in the pic. Not egg shaped. They appear to be doing their job. Take a shaft and bushing measurement to verify. Mike