Mill Oil Pump Recommendations

[20ft]

I've got an old milling machine with a constant circulation oiling system and the original pump doesn't work.

I've got a VFD on the spindle motor anyway so it probably isn't a good idea to have a mechanical pump on a belt drive like the original design anyway as it could cause problems when I slow it down or reverse it.

Hence I've decided to run a completely external electric oil pump and plumb it directly to the oil manifold/gallery but I'm struggling to come up with a suitable pump with the search terms I've been using.

I doubt a 12v diesel pump would be up to moving the iso32 hydraulic oil that the gearbox uses but I could be wrong.

Any suggestions would be appreciated

also as always the cheaper the better

 

[Newlands]

Maybe something like this:
eBay oil pump
There are a few other sellers if you look at the 'similar items', some look the same, some different, varying prices, but this one definitely promises to pump engine oil if you look at the specs.

 

[20ft]

Maybe something like this:
eBay oil pump
There are a few other sellers if you look at the 'similar items', some look the same, some different, varying prices, but this one definitely promises to pump engine oil if you look at the specs.

thanks for the suggestion, I had been considering those but it was the duty cycle of 30 minutes that concerned me but I don't know if I should just try it and see for the price

 

[northwest]

I made the error of thinking you wanted a slideway oiler but realise it is lubrication. All the same, now you are down this rabbit hole I will help you further on your way, I have one of these:

Intermittent Lubrication Pump Central Oil Lubricator 220V

Intermittent Oiler Lubricating Oil Pump Model: YESB Voltage: AC 220V Output power: 4W Capacity: 2L Output capacity: 3-6CC Interval time: 3/5/10/15/30/60MIN (optional) Weight: About 1.5KG

namicam.com

which obviously is not what you want but good to have :-)

 

[Kram]

Maybe something like this:
eBay oil pump
There are a few other sellers if you look at the 'similar items', some look the same, some different, varying prices, but this one definitely promises to pump engine oil if you look at the specs.

That would likely be too powerful as well as limited duty cycle.

How much flow and pressure does it require?

A motorcycle engine oil gear pump assembly, would need a motor, inlet and outlet adapted to your use... And a filter on the inlet.
Something like this

https://www.amazon.co.uk/Aramox-Engine-Assembly-YinXiang-Engines/dp/B09N778S8K/

 

[Newlands]

it was the duty cycle of 30 minutes that concerned me

Yes, I saw that after I posted. Maybe you could fit a switch or relay so that it only runs when the mill is actually cutting. Most of the milling I do involves a lot of stops and starts, and I don't think my spindle has ever run for more than a few minutes at a time.

That would likely be too powerful as well as limited duty cycle.

Its only a 60w pump, and given that its intended to just dump oil into a bucket it probably doesn't a a very high pressure capability. You could always drop the voltage down a bit as well.

 

[Pete.]

I've got an old milling machine with a constant circulation oiling system and the original pump doesn't work.

I've got a VFD on the spindle motor anyway so it probably isn't a good idea to have a mechanical pump on a belt drive like the original design anyway as it could cause problems when I slow it down or reverse it.

Hence I've decided to run a completely external electric oil pump and plumb it directly to the oil manifold/gallery but I'm struggling to come up with a suitable pump with the search terms I've been using.

I doubt a 12v diesel pump would be up to moving the iso32 hydraulic oil that the gearbox uses but I could be wrong.

Any suggestions would be appreciated

also as always the cheaper the better

I would not worry about the belt speed issue. What exactly is wrong with your existing pump?

If you know what the flow rate of the original pump is, it would be easy enough to match it with another. My guess is that it doesn't actually require all that much oil flow anyway for a recirculating system.

 

[20ft]

I would not worry about the belt speed issue. What exactly is wrong with your existing pump?

If you know what the flow rate of the original pump is, it would be easy enough to match it with another. My guess is that it doesn't actually require all that much oil flow anyway for a recirculating system.

I wasn't able to ascertain the problem with the original pump but I think the previous owner had problems with it because the coolant sump was full of oil where it has leaked out.

 

[20ft]

Does anyone see a problem using this pump?

https://amzn.eu/d/iFj4qap

The oil is just fed onto an open gallery with tubes attached that feed various gears and bearings so pressure will only be what required to lift the oil maybe 400mm and any excess flow will just overflow the sides of the gallery and trickle back to the pump.

All feed lines face downwards so gravity does the last bit, the pump only lifts the oil from the bottom back to the top.

I would take a picture but I'm looking through a 1/4" bolt hole to see the gallery.

I expect the original pump is an automotive part but there a very slim chance of identifying it.

 

[Agroshield]

Mentioning the name of the machine (not 'Doris') might enable us to find some instructions for it. A photo of the pump and existing drive arrangement would also be of use as would be some rough measurements of the bore of the supply and return pipes. Having a guess at the rpm of the original pump (the main motor would likely turn at 1425 rpm) based on pulley sizes is also useful information.

A lot of the big old American machines (K&T, Cincinatti) had similar oil circulation systems, so finding one of those in the same size/class could be a good guideline, as there is extensive literature for them available on vintagemachinery.org

You could adopt the Norton system: suspend a 5 gallon tank above the machine and let it drip all over the floor. There is some seriousness in this - a gravity fed system would then give you more leeway on the pump - all it has to do is fill the header tank before it runs dry. You are not going to use the machine 8h a day so a slow pump and a big tank might work for you.

 

[Pete.]

I wasn't able to ascertain the problem with the original pump but I think the previous owner had problems with it because the coolant sump was full of oil where it has leaked out.

My gear hobber pump does that. I put a tray under it.

 

[20ft]

Mentioning the name of the machine (not 'Doris') might enable us to find some instructions for it. A photo of the pump and existing drive arrangement would also be of use as would be some rough measurements of the bore of the supply and return pipes. Having a guess at the rpm of the original pump (the main motor would likely turn at 1425 rpm) based on pulley sizes is also useful information.

A lot of the big old American machines (K&T, Cincinatti) had similar oil circulation systems, so finding one of those in the same size/class could be a good guideline, as there is extensive literature for them available on vintagemachinery.org

You could adopt the Norton system: suspend a 5 gallon tank above the machine and let it drip all over the floor. There is some seriousness in this - a gravity fed system would then give you more leeway on the pump - all it has to do is fill the header tank before it runs dry. You are not going to use the machine 8h a day so a slow pump and a big tank might work for you.

The mill is a Henry Milne's Vertical Miller, the one with power downfeed and int40 spindle.

The gravity system is effectively how it's set up now just there isn't as much as 5 gallons of volume, there would effectively be no pressue as there's no nozzle or jet to form a restriction and build pressure.

I've actually found a slightly heavier duty transfer pump and I could use an adjustable power supply to reduce the flow and increase the duty cycle.

 

[20ft]

My gear hobber pump does that. I put a tray under it.

I used copious amounts of out of date RTV

 

[Agroshield]

There is a picture of the oil pump here:

Milnes Vertical Miller

Henrty Milnes of Bradford - a high-quality, tooltoom-class vertical milling machine.

www.lathes.co.uk

It is above and slightly to the right of the motor and should be accessible from the back. The might enable you to remove it and test with a cordless drill to identify any problem.

Some more useful pictures here, but nothing on the pump:

Henry Milnes Milling Machine Restoration

wallace and his Wadkin lathe (wadkin-rs-restoration-t109909.html) inspired me to make a thread specifically dedicated to my restoration attempts of my first large industrial machine. This kinda follows on from this thread: milling-machine-for-steam-engines-t108613.html?start=15 but all elements...

www.ukworkshop.co.uk

 

[minimutly]

I don't see why you can't use a coolant pump and vfd? And if that gives you too much make the pump narrower? You would need a drain from the mill gearbox to an external tank, but it would be simple. Next suggestion would be power steering pump...

 

[20ft]

I've removed and tested the original pump already using the original setup, I left it to prime for 15 minutes and still nothing.

However if I reverse the motor using the VFD the pump would also reverse and lose it's prime and not pump for a while which isn't good.

After further inspection it is entirely possible to overflow the oil gallery by pouring oil in by hand (I know it's cold so it will be slower right now) but it does at least prove I need very little flow and basically no pressure.

95% of the flow was directed over the sight glass missing the gallery and down the side of the gearbox doing nothing for lubrication.

Haxby shed used a mini peristaltic pump for his harrison which is i think what I'm going to use now because they're simple and cheap and I'm sure will easily provide enough flow to fill the gallery faster than it drips out the feed tubes.

 

[minimutly]

I've removed and tested the original pump already using the original setup, I left it to prime for 15 minutes and still nothing.

However if I reverse the motor using the VFD the pump would also reverse and lose it's prime and not pump for a while which isn't good.

After further inspection it is entirely possible to overflow the oil gallery by pouring oil in by hand (I know it's cold so it will be slower right now) but it does at least prove I need very little flow and basically no pressure.

95% of the flow was directed over the sight glass missing the gallery and down the side of the gearbox doing nothing for lubrication.

Haxby shed used a mini peristaltic pump for his harrison which is i think what I'm going to use now because they're simple and cheap and I'm sure will easily provide enough flow to fill the gallery faster than it drips out the feed tubes.

You really don't want to be running the drive backwards on a mill - it reverses the knock off stops, with obvious consequences. The guy who had my Richmond before me did this, it drove him to thinking there was a serious issue with it. In reality, swapping two conductors in the supply was all it needed.

 

[20ft]

You really don't want to be running the drive backwards on a mill - it reverses the knock off stops, with obvious consequences. The guy who had my Richmond before me did this, it drove him to thinking there was a serious issue with it. In reality, swapping two conductors in the supply was all it needed.

Very good point, I'll admit to never really using any machine tool apart from a few minutes (literally) on the Harrison L5 so I don't really know about the actual use of the reverse direction but I'd guess it's very rare.

A nice rigid setup for broken bolt removal with a left hand drill bit is all I can really think of.

In truth I've had enough of faffing with the old leaking oil pump and extracting snapped bolts etc.

If my proposed solution doesn't work then I might dig into the original pump again but ideally I want to get the mill up and running first and doing that without oil supply does seem sensible.

View it as long term temporary where if it works well then I might leave it. Of course no solution is as elegant as the original.