10EE square-dial apron oil system

[charlieman22]

Am mid restore on my 10EE.
Have had the apron on and off a handful of times as I work to get everything nicely fit and oil system properly pumping.

Had to rebuild one end of the arm due to wear.
Added a bit too much material to it and found some binding as the spring inside the lever's plunger was getting completely compressed.
Removed a bit of material and the pump is now working nicely.

Found that I get some leaking through a bolt that holds the half nuts, here:


Is this normal?
Appears this hole is tapped right into the oil supply line.
Seeing the system working now - not fully convinced about the feed to the ways.
Perhaps it will improve with any air worked out of the system.
Was surprised by how many revolutions are required by the feed rod to get a single pump cycle.
Hand wheel must be 4 or 5:1 more?
Will run and keep an eye.

 

[texasgeartrain]

Is this normal?

I wouldn't particularly expect oil to come from the bolt hole itself. Maybe it was convenient for a cross passage that intersects with that hole, and with bolt in, maybe oil goes where it needs to.

I don't know all the lube passages on a 10ee, but there could a port to keep half nuts lubed for their up/down action. I've seen a passage for threads of half nuts as well, whether its to clean debris or lube lead screw, not sure. But I wouldn't be shocked by a lube passage near that hole.

On the revolutions of pump, yeah seems not as fast acting as we might guess. Also, each pump of the pump does not necessary mean squirt action at the metering valves. They pop off at a certain pressure, could be it needs a couple/few pumps for adequate pressure to pop off for each time they pop off, assuming the metering units are in working order.

 

[rimcanyon]

The half nuts are lubed by gravity. The oil reservoir with the cotton waste at the top of the apron supplies the oil. Make sure you have enough cotton waste to hold the oil in place so it does not all run out immediately. Also check to see that the other oil lines that are fed from the same reservoir get some oil; i.e. fill it up and watch the flow. In addition to the half nuts, oil goes to each feed clutch and to the back of the apron for the feed pinion.

 

[charlieman22]

Maybe it was convenient for a cross passage that intersects with that hole, and with bolt in, maybe oil goes where it needs to.

I think maybe you're half right.
Convenient - probably.
Where it needs to? the whole idea I think was not to have oil dripping everywhere.
These guys were all about finesse.
Hell - they shaped the entire lathe like the Chrysler and Empire State buildings had a baby.
Can't imagine that allowing pressure loss through threaded hole was a planned event.

Not sure how to best stem the flow.
Open to suggestions that will hold up to petro chemicals.

he half nuts are lubed by gravity. The oil reservoir with the cotton waste at the top of the apron supplies the oil. Make sure you have enough cotton waste to hold the oil in place so it does not all run out immediately. Also check to see that the other oil lines that are fed from the same reservoir get some oil; i.e. fill it up and watch the flow.

Part of the on and off assembly as I ensured everything was working.
Reservoir is filling.
Lines are feeding.
Quite a bit of splash in the gears also helps.
Half nuts do appear to be getting drip down effect from reservoir with packing.

Having run the feed rod at decent RPM for 20+ min:
- bit of pooling on the cross feed.
- clutches lubed
- worm gear lubed
- cross feed dial fed
- far way light pooling
- near way - seems kinda dry

Oil dripping down back of apron - likely from screw hole.
Think the system has to be tight to operate fully.
Will address that next and see what it nets me.

Thanks.

 

[Mr_CNC_guy]

Oil dripping down back of apron - likely from screw hole.

Here is a suggestion: put a counter sink on either the apron body or the lead screw guide, and then put an "O" ring on the bolt. Do it such that the O ring is pressed into be bolt threads.

 

[charlieman22]

I’ll have a look at my reservoir packing - it’s possible I didn’t put enough to hold or slow the oil as per Dave’s comment above.

Here is a suggestion: put a counter sink on either the apron body or the lead screw guide, and then put an "O" ring on the bolt. Do it such that the O ring is pressed into be bolt threads.

O ring: good thought. Could execute cleanly with a small groove on the half nut. Thanks.

 

[Cal Haines]

Am mid restore on my [1960] 10EE.
...

Found that I get some leaking through a bolt that holds the half nuts, here:
View attachment 428276

Is this normal?
Appears this hole is tapped right into the oil supply line.
Seeing the system working now - not fully convinced about the feed to the ways.
Perhaps it will improve with any air worked out of the system.
Was surprised by how many revolutions are required by the feed rod to get a single pump cycle.
Hand wheel must be 4 or 5:1 more?
Will run and keep an eye.

What oil line do you think this is drilled into? Could the hole go into the gearbox area instead?

This is definitely not intentional. Someone just drilled too deep for the tapped hole. I have a one in my round-dial's apron, where they drilled for one of the screws that hold the sump cover on and went up into the sight glass counterbore. Plug it with a piece of brass or some JB Weld.

On square-dials, the apron oil pump runs anytime that the feed-rod is turning a the feed direction plunger isn't in the middle (threading) position. If you have questions about the oil system, just let the machine run for a while with the feed-rod turning and look for oil at the various ports.

 

[charlieman22]

Cal - Couldn't agree more.
I posted specifically to see if anyone else had a similar issue.
Can't imagine any scenario where a tapped hole SHOULD intersect an oil passage.
Wondered if it was a one off.
Pressure loss in this system is clearly not good.
Your fix as well as Mr. CNC's are both viable.
Thank you - I'll decide how to address when I pull it on the next round.

Your prior posts alerted me to the square dial's ability to pump with just the feed rod turning.
Having run some tests - have a better grasp of it now.
For anyone else following - the key is:
- Fwd/Rev plunger must be either all the way in or all the way out.
- Feed rod must be turning.
This runs the pump - without the carriage moving.

However: two points to be aware of that may impact thinking:
1. The feed rod runs the pump at perhaps a 1:5 ratio that the carriage handle does - its very slow.
2. Additionally - the feed rod actuates the pump on a shorter stroke. Perhaps ~ 30% or more.

The pump is being actuated at a much slower ratio - and its stroke is a fraction of the stroke it gets from the hand wheel.
In combination - its meaningful.

So the square dial does have the advantage of running the pump with just the feed rod turning, but it's running it very, very slowly, and with a shorter stroke.

Not sure I have my solution yet - will keep chipping away at making the system as tight as I can - then determine if some modifications are merrited.

 

[Cal Haines]

I'm still trying to understand what oil passage you drilled into. IIRC, there's maybe one passage in the square-dial that's actually drilled into the apron casting itself. (The round-dial has none.) The rest of the apron oil distribution is via tubing.

 

[charlieman22]

To clarify, I didn’t do any drilling.
This is likely how it came from the factory.

Not sure what passage runs behind the bolt hole I show in the picture above.
The oil is coming out under pressure - not just splash.

My assumption is:
- casted and therefore subject to some variation
- factory drilled hole to deep.
- one or some combination of those two.

I don’t know the castings to identify what passage likely runs behind that bolt hole - but it’s clearly under pressure as it leaks past even with a bolt fully threaded in.

Thoughts?

 

[rke[pler]

Maybe use some hydraulic thread seal on the bolt?

 

[texasgeartrain]

Its a bored passage. I got to my other location, and happen to have a square dial apron on the bench.

I didn't investigate hard enough to tell you where oil is supplied, but there's a flush pipe plug from top side. Note the allen wrench:


Removal of that plug, the passage was still filled with oil on mine. Slipping a small screw driver down the bore, I can feel the intersecting bolts holes, and it feels like both my bolt holes hit that passage. That passage is pretty deep, I can drop the screw driver all the way down.


You could do the oring thing. Prolly get away with some sort of sealant on bolt threads as well.

 

[Cal Haines]

Its a bored passage. I got to my other location, and happen to have a square dial apron on the bench.

...Removal of that plug, the passage was still filled with oil on mine. Slipping a small screw driver down the bore, I can feel the intersecting bolts holes, and it feels like both my bolt holes hit that passage. That passage is pretty deep, I can drop the screw driver all the way down.

...

View attachment 428548 View attachment 428549

You could do the oring thing. Prolly get away with some sort of sealant on bolt threads as well.

Wow, whoever was into your apron last really went wild with the gasket/sealant. The reservoir at the top of the apron (to the right of the screwdriver) is completely covered over:

That reservoir distributes oil to the feed clutches plus feed-rod worm gear & wheel. The oil comes from a right-angle fitting that should be directly below the hole with the screwdriver. There are two diagonal passages that intersect the vertical passage. One branches off to the right (in the above photo) at about 45 degrees and has a Bijur pressure relief valve screwed into it to feed the reservoir at the top of the apron. The other branches left and meets a vertical hole with a counterbore and O-ring that feeds oil into the saddle. It looks like the left-hand diagonal passage is drilled in from the bottom of the casting, starting near where the right-angle fitting is found. It would be nice to verify all this and document the locations of the holes and how they are plugged.

To the main question, there's no reason the bolt hole for the half-nut bracket needs to go that deep. I would probe the depth of the hole and verify that it goes through to the vertical passage and compare it's depth to the length of the SHCS. I bet there's plenty of depth to insert a setscrew to block the bottom of the hole. If necessary, I would tap the hole deeper.

 

[charlieman22]

Everything in TGTs post aligns with mine.
Bolts (if long enough ones used) likely go right into that passage.

Dave’s hydraulic thread seal seams a no brainer for simplicity and likely effectiveness - quick search online has a number of them for the purpose it seams. Thatl b my first move.
Should bring my pressure up.
Love seeing the pooling on the cross slide.
Want to see it on my ways before I’ll claim victory.

Thanks for taking the time to have a look at your apron.
Suspect I painted right over that flush pipe plug - but for sure that’s the channel.

 

[rke[pler]

I don't remember that oil passage as being to that part, I recall the passage for the half nuts as bring on that side of the top half and only lining up when the nuts were closed. What's on the back of the bracket that the half nut slides in? Looks like there was a hole drilled through about where that passage exits. Here's a picture of my '56:

 

[daryl bane]

Here's mine, just for documentation. I can see if the bottom hole is drilled alittle too deep it might intersect with the oil hole on the ways of the half-nut. I don't remember what that allen bolt is doing between the oil pipe and where the half nut brackets bolt on.

 

[charlieman22]

Daryl, I believe that allen bolt you have in there belongs to the top left ear of the worm gear cover.
Perhaps you just screwed it back in after removing the cover to keep it in place.

If you look - there is a hole (see arrow) that lubes the half nuts.
I suspect the same channel that is punctured on mine, feeds this.


I am fairly confident that my half nut bolt hole was simply drilled too deeply in production - and based on TGT's post - I'm probably not the only one.

I've been using the machine for the past few days.
The oil system is working better than I thought it would/did.
I have pooling in all critical spots - after a few hours use - as I was advised I would.

I'm going to seal up these threads - to get rid of any pressure leaks - and see how it goes.
Generally - I'm pleased to have oil flowing to critical components.
I always hated oiling the ways - just to watch the wipers Zamboni most of it away.

 

[Cal Haines]

Here's a section of a drawing that shows the square-dial apron's pumped lube system:

It's clear to me that the tapped hole was drilled too deep and hit the vertical oil passage. OP can verify that by sticking a wire into the tapped hole and probing the vertical passage with a screwdriver, as TGT did. Personally, I would not just seal the bolt up with goo and leave a problem for the next guy; I would do a proper repair.

 

[Cal Haines]

...
If you look - there is a hole (see arrow) that lubes the half nuts.
I suspect the same channel that is punctured on mine, feeds this.
View attachment 428771
...

I'm pretty sure that the half nuts are gravity fed from the reservoir at the top of the apron.

 

[charlieman22]

Cal - thanks for posting the cross section.
The apron will come off again when I paint the lathe body.
I’ve been cycling it on and off - to repair the oil system and paint/polish - getting old hat.

I’ll retest and photograph the half nut hole I pointed out on next tear down - but I’m fairly sure it’s feeding the half nut “ways”. There really would be no other reason to have a home there - and it’s an optimal way to keep the sliding surfaces oiled.

Some good suggestions in here for fixing the over bore.
what ever I do, I’ll post it with my restoration thread.
But for the record, “the next guy” will have to bring a cherry picker or rolling gantry crane to my grave sight if they wanna get hold of my machine.