Rauce
Ultra Member
Hey folks!
We just got a new (used) lathe at work. This came about through a friend of mine who manages the machine shop at a heavy equipment manufacturer. It’s been redundant for some time and they needed space for a new CNC. Their usual machine tool dealer they work with offered them scrap value so I got the go ahead and outbid them on it by a couple hundred bucks.
Our outgoing lathe is a terribly worn TOS SN50. The colchester has some visible wear but in a head to head test cut it had 4x less taper!
I gave it a bit of a clean up and got the electricians to connect it. After going through the manual and getting it started I realized it wasn’t circulating oil properly. Did some investigating and got it to start moving oil by priming the pump.
Oil for the headstock is in a reservoir under the chip pan and coolant sump. It gets pumped by a small gear pump on the end of the countershaft that has the clutch mechanism on it.
Once it started moving oil it started making quite a bit of noise. I took the pump out and found it was pretty badly worn on the pinions and the oilite bushings. It appears that at some point it was run with the motor phased in the wrong direction and without oil moving through the pump it got chewed up. Couldn’t have been for that long since the headstock gearing seems to be in good shape.
I’ve ordered new bushings and made a new pinion shaft but the pump gears are not a readily available part. I suspect once I get the bushings replaced it will quiet down a bit but it would be nice to have a plan for new gears.
So with the backstory out of the way, does anyone know if gear pump gears are typical spur gears? The two gears are the same size, one steel and once bronze. They both have 8 teeth and an OD across the tips of the teeth of 1.098”. I can take some pictures tomorrow for reference.
We just got a new (used) lathe at work. This came about through a friend of mine who manages the machine shop at a heavy equipment manufacturer. It’s been redundant for some time and they needed space for a new CNC. Their usual machine tool dealer they work with offered them scrap value so I got the go ahead and outbid them on it by a couple hundred bucks.
Our outgoing lathe is a terribly worn TOS SN50. The colchester has some visible wear but in a head to head test cut it had 4x less taper!
I gave it a bit of a clean up and got the electricians to connect it. After going through the manual and getting it started I realized it wasn’t circulating oil properly. Did some investigating and got it to start moving oil by priming the pump.
Oil for the headstock is in a reservoir under the chip pan and coolant sump. It gets pumped by a small gear pump on the end of the countershaft that has the clutch mechanism on it.
Once it started moving oil it started making quite a bit of noise. I took the pump out and found it was pretty badly worn on the pinions and the oilite bushings. It appears that at some point it was run with the motor phased in the wrong direction and without oil moving through the pump it got chewed up. Couldn’t have been for that long since the headstock gearing seems to be in good shape.
I’ve ordered new bushings and made a new pinion shaft but the pump gears are not a readily available part. I suspect once I get the bushings replaced it will quiet down a bit but it would be nice to have a plan for new gears.
So with the backstory out of the way, does anyone know if gear pump gears are typical spur gears? The two gears are the same size, one steel and once bronze. They both have 8 teeth and an OD across the tips of the teeth of 1.098”. I can take some pictures tomorrow for reference.
