12x36 spindle bearing

BruceW

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I have a new to me Mc Milligan 12x36 lathe and in the process of putting new spindle bearings in is it w run dry for a length of time.
generic lathe.

The rear bearing arrangement has me a bit puzzled.
How does it not leak oil

There is a small area which the spacer with the key way can mate with the bearing race.
with the taper of the inner race outside edge is is quite thin.

both rely on the finished surface to seal the way I see it.

here are some pics.
0AF8DDCC-C335-479E-BD97-0FF8EE7E6E63.jpeg


8BBDA117-F726-4E28-81E4-B8AD632D3287.jpeg

I hope someone can enlighten me before I throw it all back together with new p5 bearings and seals.
I don’t want to do this again as it has proven to be costly.

I don’t know how well she runs ‘cos I thought I’d pull the spindle to change the belt and found they were not the best of shape.
Any help appreciated
Bruce
 
Some have an oring in a groove on the inside of the sleeve to help seal, others use silicone or even a heavy grease. It is a very known sore point for users of this style of lathe. I have one at home and there is a Jet equivalent at work. One leaks the other does not yet.
Pierre
 
Thnx.
I got an o-ring today that fits well should seal perfectly inside the spacer.

The keyed section of he geared Bush I may try and plastic metal in the end of the key way and a a and ptfe tape might provide a seal on the take up nut.
Drop of Loctite on the clean mating surfaces of the bearing and glad maybe all it takes.
I thought of a soft copper crush / seal washer to provide a seal in the bearing bush area but couldn't’ find one large enough.

Thanks for the thoughts And insight.
It was defiantly made to the engineers drawings; that’s for sure.
ha
How do you find the lathes to use?

I‘ve been looking for a quiet belt driven lathe for a long time to tinker on.
Just tool steel mostly old school don’t bother me.
done my apprenticeship on ‘ol war horse turrent lathes and such with flat beds.
They were nice to use when tuned up.
Will make chips soon, fingers crossed
Bruce
 
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I find they are easy working lathes. Sure, you have to change a gear or two if the thread is different but coming from an Atlas at home, not a problem. No worst than working on old cars and trucks.
Pierre
 
It’s alive.
C69DAC77-15FA-4432-B464-D22CC4A3AB41.jpeg

I ended up using the damming of the key way at the end so it wouldn’t get in the road of things.
I assembled the headstock and snugged it down with the spindle held firm by the tailstock and removed the key spacer.
Then put some Black gasket silicone in side it then snugged it back up.
let it all set for 24 hrs.

92F63699-FD02-4A08-A043-E0BD2426A43B.jpeg

I have played with the adjustment a bit and thought I had it too tight.
It ran hot so I backed it all off to 5 thou then 2 thou end play ran it for a while to let it settle.
I wasn’t getting hot today so I tweaked it to 1 thou and see how it goes.
It works quite well.
‘Cuts nicely and even leaves a respectable finish on gal pipe.
Nice and quiet without the gear train engaged and cuts nicely.
I have a little problem with the spigot that holds a gear and pivots the banjo being a bit out of sorts a few thou.
It has a tick tick sound as the gear in the spindle runs on the forward /reverse gears but the spigot pushing them up to much.
I will sort it out thou.



I thought I bought 2 pieces but instead got 2x 5 packets of 1/4" round m35 tool steel. I wondered why they seemed so more expensive than square stuff.
I’ve played around and made a boring bar and round tool steel holder.
I used the lathe to drill them on centre Height so I don’t have to use packing.
lifted the back end up on the tool holder to give me a bit of angle ley way.
Works O.K. So good enough.

Now I just have to Grind the round bar exactly half way through to make it work.
Dohh!
I even thought of maybe a couple of thumb wheels on the base of the holder for height adjustment.
Or just find a bucket load of various packing.
I learnt to hide my packing when I worked as a apprentice as it always grew legs if I left it about when I went to tech.

I suppose apart from learning how to use a machine tool all over again after 25 years absence is...

How do you keep the swarf from immigrating into the house?
SHMBO will not like to dig bits of steel out of her feet or the dog for that matter.
Thanks for the help much appreciated.

Now I just need to put the grinder up off the ground, build a bench, a mill attachment, a wee internal Threading bar........... tool post mill drill and ..........
‘OMG what have I done.
Thanks for a help much appreciated
Bruce.
 
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