BP clone leaking oil

[dlane]

Seems my supermax mill is leaking oil more than it used to. The spindle oil cup doesn’t keep oil in it very long, anyone know if there’s a seal in there or what might be going on ? It’s slinging oil around
I’m using 10w spindle oil in both the quill and spindle cups as per manual
Thanks

[4GSR]

Yeah, fun isn't it?  I suggest using a 20-30 wt oil, unless your spinning the spindle over 1200 RPM's.  3 to 4 large drops of oil daily is all it needs. The more you put in it, the more that leaks out.  Just a little bit daily is all it needs.  If you can add a drip oiler to the head, do that and regulate the needle to one drop every two to three minutes or so.  And that is still too much at times.

As for adding a oil seal to the lower bearing cap, you can try it.  Make a whole new cap so that way if it don't work right, you can always put it back to original.

Ken

[strik9]

My ex boss has a wartime Richmond (?) heavy duty drill press with huge bearing play.  A brass plate identified the seller to a London, England address. 
 
  It was wore out by 1954 and never retired.  We put sticky truck axle grade oil in the gearbox and before big jobs in the cups.   
    The leak runs down the quill and over the chuck onto the drill nit and work.   We simply call it an auto oiling feature.

[4GSR]

I've seen Bridgeport mills go weeks on end, even months on end before someone squirted some oil in the cups.  It was generally me that did it, too.  Gorton mills are set up the same way, too.  At least they had a drip oiler that you could control the amount of oil it let go.  Bad thing to that, if you forgot to turn it off at the end of the day, vise and table was generally covered with oil the next day!

Ken

[dlane]

The mill runs quiet, maybe it’s the 100* heat thinning the oil, but is there somthing in there to retain the oil or slow it down?.

[4GSR]

The mill runs quiet, maybe it’s the 100* heat thinning the oil, but is there somthing in there to retain the oil or slow it down?.

There's really not anything in the spindle to retain the oil in the spindle.

You want it to drain thru, that's how it keeps the oil fresh in the bearings and run cool.  If you retain the oil, the bearings will run hot with all that oil churning in the bearings, not good!  Just back off on feeding it oil and feed the spindle a few drops of oil a day and you'll be fine. 

In high dollar CNC machine tools, the oil is recirculated, filtered and injected into the bearings as a mist, that amounts to a few drops of oil per minute.  Those bearings are three times bigger than that on your size mill.

Ken

[cathead]

You could take a look at the spindle cup oiler and pack it a little tighter possibly.  Generally there is a felt plug and a wick of sorts
to control the drain rate.  If the packing has dislodged, the symptoms you mention will be evident.

[pep]

 Purchased a mill, and listing to others bought Spindle oil, Mobil 1. Noticed that when the mill sat talking days here. The table and vise became wet, as the oil was weeping.

No one likes oil leaks, when all else fails .....go to the user manual. I'm posting what I learned  for the discussion, not suggesting it's a fix for others.

It did help, and has controlled the problem significantly.
Pep


*****************
LUBRICATION
Oils are classified according to their viscosity. There are several viscosity indexes, the main ones being ISO (International Standards Organization) and SAE (Society of Automotive Engineers). SAE adds another complication with different indexes for engine and gear oils, further sub-divided into lists with and without the suffix W, meaning "multigrade". Mistaking SAE engine oil for gear oil can be an issue; for instance, SAE 20 engine oil has about the same viscosity as SAE 80 gear oil, both roughly equivalent to just one number on the ISO scale, ISO 68.
Recommended lubricants
Gearbox: ISO 68, such as SAE 80W90 auto gear oil, or Mobil DTE Heavy/Medium circulating oil (about 2 qts.)


Ball oilers (X and Y leadscrews): ISO 32 oil, such as 3-IN-ONE (the "motor oil" version of this brand is heavier, about ISO 68, but it can also be used)
X, Y and Z axis ways (dovetails): ISO 68 oil, such as Mobil Vactra No. 2, or equivalent
Power feed (visible gears), quill rack and pinion, Z-axis helical gears: light general purpose grease, NLGI No. 2, or equivalent
X and Y leadscrews: ISO 68 oil, such as Vactra No. 2 or 3-IN-ONE Motor Oil
Z leadscrew: ISO 68 oil or NLGI No. 2 grease

[PJB]

Seems my supermax mill is leaking oil more than it used to. The spindle oil cup doesn’t keep oil in it very long, anyone know if there’s a seal in there or what might be going on ? It’s slinging oil around
I’m using 10w spindle oil in both the quill and spindle cups as per manual
Thanks

Mine does that too. Same stuff 10W spindle oil.    I chalk it up to me pulling the pipe cleaner looking wick thingy out thinking it was someones dumb idea.  In reality, I have come to realize it was in there for a good purpose.    IMO its good and bad having the oil perpetually leaking.  Bad when I forget to wipe up before turning on the spindle.  So many shirts strafed with oil stains and it tastes bad!   Good because it forces me to wipe down the spindle area and keeps everything nice and clean.  Always fresh oil purging thru.  This is how I find my mill when I haven't run it in awhile.  Definite oil dripping from upstairs.


 

[4GSR]

PJB's mill is what you want to see from oiling.  And it don't take much oil per day of running either.  As I said, just a few drops is all it needs per day. 

And please don't put gear lube in there for spindle lube.  That will destroy a precision set of bearings almost over night.

Ken

[pep]

 Was going down the wrong road, read ISO 68. Then thinking ISO 68 is ISO 68 and not giving proper consideration to the additives. Did know 90W gear lube was not going to work, and not used.

Reading it's normal for some lubricant to be weeping in the quill area. And one of those never discussed normal related events outside of the shop environment.

 Changed back to the spindle oil.

Over night bearing destruction was funny had a mental picture of a worry wart running around with hair on fire. LOL.

Thanks for the education and the laugh...

Pep

[dlane]

I’m using what the manual says “spindle oil 10 wt”  no gear oil, just seems to be leaking more than it used to. Sounds and runs great