Should my apron be full of oil?

[Threadkiller]

Hey all. I have a Soutbend 9A, quick question. Should the apron be full of oil like a sump? I always oil my lathe before use and the other day I saw that the apron had a drain plug so I figured I would get all the old junk out of there and I opened it and its dry? Im always dumping oil in the cups. So I was wondering if the clutch assembly is supposed to be sitting in like a sump of oil or it just gets oil from the cups as needed?

 

[dbb-the-bruce]

Short answer - yes.

Poke around for some details or videos, the inside of the apron is quite a piece of work. multiple wicks provide oil from the "sump" etc.

Also it's recommended to use two types of oil on the apron. If I recall correctly the clutch should get A (spindle) or maybe B and the hand wheel gets C (check the rebuild and maintenance docs and vids).

There's a ton info out there and many posts in this forum.

 

[Ulma Doctor]

Hey all. I have a Soutbend 9A, quick question. Should the apron be full of oil like a sump? I always oil my lathe before use and the other day I saw that the apron had a drain plug so I figured I would get all the old junk out of there and I opened it and its dry? Im always dumping oil in the cups. So I was wondering if the clutch assembly is supposed to be sitting in like a sump of oil or it just gets oil from the cups as needed?

Yes, your apron should be filled with oil.
The clutch and other parts will wear rapidly without the presence of oil

 

[piper184]

I fill mine every time I use it and it is dry the next day. Always a drop on the bottom of the drain plug. Have checked the plug and the gasket but can't tell where it leaks. Seems to be common with these aprons.
Operate it like an old motorcycle, if it ain't dripp'n it must be empty!

 

[Jake M]

The apron is open in the back, but there's a small space at the bottom that holds oil. Kind of a reservoir of sorts I guess. It should be kept full.

The "sump", or the reservoir gets spindle oil, type A, the number ten spindle oil. That is the 90 degree cup that hard to get at though the feed wheel, which lives next to the clutch knob. That lower one fills the reservoir. Everything else on the apron gets general purpose type C, ISO 46.

They do leak. There's always a drip on that plug. That's where the oil ends up when the reservoir gets overfilled. It will overfill, because in the end some (not all) of that type C that goes "everywhere else" will run down there as well as the spindle oil. The overflow comes down the back of the apron and looks like the plug is leaking. (Or the back cover can leak too, but it's sooooooo little..... Most of it's overflow). The plug is the only part of that system that doesn't leak, but that's where you sit the pan under it when you're done for the day.

First Google Image that shows the back side of an apron.....

https://i.ebayimg.com/images/g/lpkAAOSwLSRj6Rnc/s-l1600.jpg

Edit-
I just want to toss out there, Every document I have says that type A goes in the reservoir, and type C goes everywhere else. I have seen other charts all over the internet that call out type C for EVERYTHING in the apron including the reservoir. My gut says that you won't blow it up either way, but the thinner oil in the reservoir would probably be beneficial, even if it's only in theory. But I'm guessing that either way can't be "too" wrong...

 

[dbb-the-bruce]

The "sump", or the reservoir gets spindle oil, type A, the number ten spindle oil. That is the 90 degree cup that hard to get at though the feed wheel, which lives next to the clutch knob. That lower one fills the reservoir. Everything else on the apron gets general purpose type C, ISO 46.

Agree. I was not trusting my memory this morning. Also agree that you won't blow it up if you use other stuff. I did for years. I finally got on board with the A, B, C system when I rebuilt my apron, tail stock and headstock.

BTW - the rebuild of the apron recommends using a good gasket sealant when you replace a gasket that's in there. My apron no longer drips oil to the extent that it did. So properly cleaned and reassembled shouldn't leak much based on my singular experience. That may also be influenced by my less excessive oiling since the rebuild. Being new to all of this years ago when I got the lathe I chose to err on the side of to much oil as it doesn't hurt just makes more of a mess.

 

[woodchucker]

Here's another pic w/out the gasketed cover. There's not much oil in there, since there is not a lot of room.
I have drained mine, to make sure it's clean. I do it every year Jan 1st. along with other maint.. compressors, tablesaw.... etc.

 

[Threadkiller]

Wow, this forum is great. Thanks guys. I never knew there was a sump in there until I saw the drain plug and that got me thinking that there definitely should be some oil sitting in there. I guess ill just keep dumping oil until i see it dripping.

 

[dbb-the-bruce]

Just a thought based on my own personal experience.
When I first got my SB 9a it was it very good condition other than the fact that someone had used heavy grease on the head stock to quick change box drive train, and also the lead screw. I scraped if off (including all the crude it had accumulated - particularly on the lead screw) and decided to just leave the rest as is.

When I eventually screwed up and did something stupid (abrasive) it became mandatory for me to remove and clean the apron. I also decided that I might as well rebuild (actually disassemble, clean and re-felt) the apron.

My observation is that it's really not that hard to remove the apron without fully disassembling it. Once removed you have access to clean out all the years of accumulated junk, flush it thoroughly, remove the plate over the sump and redo the gasket. All of this is less work than a full tear down and you are unlikely accidentally damage anything (from lack of experience with this sort of stuff). So one could fix a leaky sump and clean up without a full rebuild effort.

I guess this rarely comes up because it mostly a "I've gone this far, might as well do the full job".
So my point is - don't be afraid of removing the apron and at least inspecting and cleaning it out. It's surprisingly easy. At that point you can decide if it is working good enough or if you really should do the full tear down.

As an example, mine didn't leak but the clutch nob engage/disengage was a little wonky/sticky. Tearing it all apart and putting it back together fixed this issue. But I could have lived with it as I already had for years.

 

[SLK001]

It's more like a reservoir than a sump. The worm gear and clutch "bathe" in the oil in the reservoir and via transfer, keep the worm oiled. A lot of felts originate in the reservoir to transport the oil where needed elsewhere. Type A oil wicks better than Type C, so use the Type A oil for the reservoir.