What's new
What's new

Graziano 12S Headstock Oiling System

ACHiPo

Aluminum
Joined
Sep 16, 2012
Location
E. Bay, CA USA
In preparing to change the headstock oil in my new-to-me 12S I pulled the filter. There is quite a bit of metal and sludge in it. What have others observed when the filter is pulled?
IMG_0330.jpg

Also, the oiling tubing seems different than what is in the brochure. Can others post photos of their headstock oil circuits?
Here's mine:
IMG_0327 (Large).jpg
IMG_0329 (Large).jpg

The photo in the brochure shows a connection to the bearing at the left side of the headstock.


Thanks,
Evan
 
I pulled the drip tray and took a few more pictures. I can see some wear on the gears, but nothing nasty. On my machine, the spindle bearings are open and lubricated with oil spray by two copper tubes directed at the bearing tops. In the brochure the bearings look to be plumbed directly to the manifold.

IMG_0347 (Large).jpg
IMG_0339 (Large).jpg
 
Your copper tubes look clean and straight. Mine were a bit abused.

In my lathe its the same setup.

Yes in the drawings it looks like there a direct link from the bypass block to the front bearing.
If you disconnect the bypass block you will see that there is a blocked hole at the bottom part and
suitable hole in the head stock casting.

I have thought to open it but after second consideration I installed it as is. They probably head a
bypass there but later on decided that a copper tube flushing the bearing with oil is better. You had so
much dirt in your filter I strongly suggest removing all the tubes and make sure they are clean.

Also I suggest using a spray gun (see image) and spray the front and back bearings with Kerosene or white
spirit while rotating the spindle by hand. Try to clean it the best you can as the head stock main bearings
are expensive (about $100 each or more) and replacing them is not simple.
 

Attachments

  • kerosen_gun.jpg
    kerosen_gun.jpg
    3.3 KB · Views: 33
You had so
much dirt in your filter I strongly suggest removing all the tubes and make sure they are clean.

I drained the headstock yesterday. The extension tube unscrewed from the casting rather than the drain plug, which made quite the mess. I was able to route most of the oil into the drain pan, but more than I liked ran down the casting, sheaves, and motor. Fortunately I had PIG pads to sopp up the oil. I mopped up the remaining oil and what grunge I could in the bottom of the case with paper towels.


I flushed the headstock with mineral spirits (less viscous than kerosene), paying special attention to flooding the bearings. I mopped up the grunge in the bottom of the casting with more paper towels. The mineral spirits reacted with something in the remaining oil and created small flecks of whitish slippery stuff like paraffin. Thinking it was good to get rid of that stuff, I wiped out as much as I could then flushed the area with denatured alcohol, again flooding the bearings and rotating things by hand, followed by wiping everything down with paper towels.

I've pulled the tubes and blew compressed air through them. The flow seems good. I confirmed that the air also spins the oil flow indicator as long as I put my thumb on the open manifold fitting.

I decided not to pull the sight glass, but did reach into the case and clean the glass with a Q-tip.

I refilled the case with ISO46 oil, making sure to splash oil into the bearings while rotating the input shaft slowly.

I ended up adding about a liter too much oil, so am now waiting for a big syringe and beaker to remove the excess.

When I rotate the input shaft a few rotations I am getting oil into the flow indicator, so the pump is working. I'd like to see a little more flow even when I rotate the shaft by hand, but maybe the input shaft needs to be spinning at 50 RPM or more to get noticeable flow?

Also, it's clear the pump only pumps when the spindle is turning since the pump is mechanical and driven off the input shaft. The manual makes a big deal about making sure the motor is wired such that the motor rotates correctly so the oil pump works. How is oil pumped when the gearbox reverses spindle direction?
 
I don't have a manual handy. So I'm not sure if theres a pump in the gearbox. That would likely require the input rotation to be correct.

The spindle is not likely to be run for extended periods of time in reverse doing typical lathe work. So not the same issue as the gearbox, which is spinning whenever the motor is on.

I dont think I've ever noticed whether the flow indicator spins in reverse. Or if there's an exploded view of the pump. And I'm no expert on pumps either, but maybe there's some chance it pumps running in either direction?
 
Wes,
Thanks. There is only a pump in the headstock according to the manual. The spindle and gear box just have splash oil distribution.

The pump is a manual eccentric design per the drawing (which is not very good). This lathe has a duplicator mounted, which only works when the spindle is running in reverse, so it likely saw a lot of reverse time.

Just trying to understand thing before buttoning it back up.

Evan
 
Also, it's clear the pump only pumps when the spindle is turning since the pump is mechanical and driven off the input shaft. The manual makes a big deal about making sure the motor is wired such that the motor rotates correctly so the oil pump works. How is oil pumped when the gearbox reverses spindle direction?

Evan,

It's very possible that the oil pump is a vane pump. Many vane pumps will pump in either direction. The warning given in the manual about insuring that motor direction is correct may only be to insure that the direction of spindle rotation corresponds correctly with the selector switch on the control panel. You may be able to verify this by doing what you did to prove that the oil pump was pumping by just rotating the input shaft in reverse direction by hand.
Just some food for thought.

Ted
 
Hi All,

1 litter extra oil in the head stock is not so bad. The bearings and all needs good lubrication so do not worry.

As for the gear box and carriage this is a different story. The carriage auto feed leaver mechanism is not sealed.
and if you over feel it it will go into the leaver box and then leak out.. I learned that the hard way.

One suggestion is to buy a brass angle and use it when you refill oil. You only have one 90 degree angle in the machine
but in the carriage, Norton box and gear box its straight and that makes it a bit difficult to fill.

As for the gear box it does not have any oil seals and I found the hard way that if I fill to much oil it over floades
and goes out in the bearing flung. I have a (not nice) leek there and this should fixed.

Keel the good work and be patient..
 
When I changed the oil on mine, I added a short nipple and 45 deg El on each one, so the next time would be easier and hopefully cleaner. And went overboard by installing a ball valve on each one as well. Took the handles off so the door would clear, and to prevent an accident if they got bumped.

Taped everything well, and they still leak. Oh well, it's due again anyway, and I've gotta seal the quick change cover as well.

I overflowed the apron as well. It didnt show in the window, and the splash I gave it was more than my estimate of how much volume it has. So the window got completely covered leading me to believe it still didn't have enough. So, add a bit more ...
 
Wes,
That's what happened to me and the headstock--by the time I checked the sightglass it was already overfull. The new oil (not surprisingly) is a LOT lighter colored than the old stuff!

Ted,
I'm going to try to get a 1/2" drive for that will fit in my cordless drill. I can't spin the shaft fast enough by hand in either direction to move the oil indicator. I suppose I could pull the indicator and filter out (again) and look for drips.

Thanks,
Evan
 
Here is a drawing from the manual showing the pump. I thought it is an eccentric vane pump. I can't remember where I read that it only pumps in one direction (maybe I imagined it?)
Graziano 12S Headstock Oil Pump.jpg

From the drawing it doesn't look eccentric?
 
Appears someone stole all your headstock gears!

Any date markings on electrical components? Surprised there's copper oil feeds, the larger machines went nylon by the mid 70s at least.

The pump indicator vane won't spin with the chuck going in reverse on the 210 with pretty much the same arrangement of pump, etc. There's at least 2 or 3 outlets that just deposit oil out of open ended tube onto various gears and you'd suck air if it reversed. The 12S without the additional lubrication requirement might be good both ways....hand spinning wouldn't achieve zip, unless you're Lee Majors.:D
 
On the Sag 12, the headstock oil pump works in forward and reverse directions.

Vane pumps can't normally do this, but the Graziano pump is a clever design which does!

Discussed recently on another thread, see post #4 for photos and explanation.

Sag 12 Headstock Not Pumping Oil?

The Sag 12S pump drawing above looks the same, I am guessing it also pumps oil in either direction.
 
On the Sag 12, the headstock oil pump works in forward and reverse directions.

Vane pumps can't normally do this, but the Graziano pump is a clever design which does!

Discussed recently on another thread, see post #4 for photos and explanation.

Sag 12 Headstock Not Pumping Oil?

The Sag 12S pump drawing above looks the same, I am guessing it also pumps oil in either direction.

Fantastic information. I'd read Texas Turnado's post, but missed this tidbit. Thanks!
 
The 12S without the additional lubrication requirement might be good both ways....hand spinning wouldn't achieve zip, unless you're Lee Majors.:D
No 6 million dollar man here. Just ordered 1/2" socket drive adapters so I can use my drill to test before buttoning up.
 
Hi,

Any one has experience with oil seals ?

I have replaced the two oil seals in the shafts that go the external gears. One from the head stock and one from the feed box.

I have cleaned it all, made sure that everything looks OK. I oiled the internal and gently hammered it into place.
It seems ok and there is no leak when the machine is not working.

When I start it for a short time (maybe 15 minutes) I am getting oil leaks. It looks like that the oil seals are leaking.
I wonder what did I do wrong and can be done to get better results. I am planing to replace the Nitril oil seals with
Viton seals but I do not think it will make a big difference.

Any ideas would be appreciated.

Thanks, Noam.
 

Attachments

  • feed_box.jpg
    feed_box.jpg
    20.4 KB · Views: 38
  • head_stock.jpg
    head_stock.jpg
    19.4 KB · Views: 37
Hi,

Any one has experience with oil seals ?

I have replaced the two oil seals in the shafts that go the external gears. One from the head stock and one from the feed box.

I have cleaned it all, made sure that everything looks OK. I oiled the internal and gently hammered it into place.
It seems ok and there is no leak when the machine is not working.

When I start it for a short time (maybe 15 minutes) I am getting oil leaks. It looks like that the oil seals are leaking.
I wonder what did I do wrong and can be done to get better results. I am planing to replace the Nitril oil seals with
Viton seals but I do not think it will make a big difference.

Any ideas would be appreciated.

Thanks, Noam.

Noam,
I've got some experience with shaft seals from a long time ago and a totally different application. Not sure it would be helpful, but willing to try.

What type of seals did you install? Were the original seals leaking before they were removed and replaced?

Evan
 
Hi Evan,

Originally there was ZERO oil in the feed box and about half a liter oil in the gear box... yes the machine was leaking.
I am not sure it leaked from the oil seals but I decided that if I am overhauling it its better to replace them.
The whole area at the belts was wet from oil...

I fixed the head stock oil pressure (rotor and filter) sight and feed box leaks. I sealed the head stock cover and
in general its much better then before.

I think that maybe its not the oil seals but rather oil dripping from the head stock cover down and wetting everything
so the shafts and all are wet.

I am not fully sure that the oil seals are leaking but it looks like that.

I installed double lip rubber oil seals. The one I have removed were probably not the original ones. As far as I
understood the original seals were single lip with external metal ring.

I have installed just standard double lip Nitril seals that I got locally.
 
Noam,
I remember you had quite a bit of leaking in the feed and gear boxes, but I thought the feed box leak was mostly the front seal. I don't remember what you found for the gear box leak?

If I understand correctly, you replaced the seals on the headstock. I was just wondering if the shaft(s) could be scored and causing a leak, in which case a seal wouldn't help.

I've used carbon-filled Delrin seals, kinda like this:
DDS Dual Lip with Spring Rotary Shaft Seal with 16mm Inside Dia. and 28mm Outside Dia. - 53XC52'|'16287TCV - Grainger

I've also used "X" profile buna-N seals:
Double X-Profile Oil-Resistant Buna- N O Rings Supplier,Manufacturer,Mumbai,India

Not sure if either of these would be better for the application. Again, my experience is not with sealing gearboxes, so hopefully someone more knowledgeable can weigh in.
 








 
Back
Top