I was getting chatter when facing 6" dia steel loco-wheels on an ancient Colchester student 1200. Judicious use of a pry-bar between the back of the chuck and the gearbox face showed 5 thou end-float, so off with the top cover and have a look. The headstock shaft bearing-adjustment locking tab had lost an 'ear', allowing the castellated ring to work loose. I am only a hobby engineer, so it was hand- tightened it so it would still turn, then backed off to the nearest available locking tab, (like a car wheel bearing), but still turned freely with no detectable slack. I didn't wash the box out, as I didn't want to get bits in the rollers and trash them. The box oil was very low, so I topped it up to half a glass with hydraulic oil (straight 32) from a local machine shop that keeps bulk for their own lathes.
I think your right them rollers don’t look right. Max grant swan valley machine shop as just done a series of videos replacing headstock bearings he made sure they were all turning. He definitely knows what he’s doing. We have that same machine at work and that tapered pin that broke are roll pins in ares (don’t know for sure if they are original but I think so ) this series of videos you have done as been really interesting and helpful. Thanks very much for for taking the time to make them all the best I’m sure you we’ll get it sorted 👍👍👍
More good progress Samuel, always an interesting watch, I did notice the rollers moving , you would think with only 0.002 mm endfloat they would be held captive. There is a guy on youtube Haxby Shed with a Harrison 140 lathe, he has covered the lubrication of the headstock among other interesting stuff, although not the same model as yours, it has some similarities, cheers Dave
Thanks. I have watched Haxby Shed in the past but hadn't noticed his work on headstock oil pumps. It seems he found exactly the same "problem" that I noticed: oil not being splashed upwards enough (at any rate using the gear ratio that allows me to drive the spindle with my electric drill).
Samuel. Just a thought and not having the advantage of handling the spindle assembly and looking at the preload arrangement, these taper bearings being back to back I would guess the 2 micron end float ensures the rollers are not actually loaded in the free state, being such a precise assembly the rollers would perhaps 'roll' ensuring lubrication. Also when the main spindle is under load and expansion takes place would this increase or decrease the end float?
Another thorough job and a pleasure to watch. Just a point of interest. I rarely see you use an airline and have no doubt you have a compressor, as I cannot work without an airline can you comment?
@@samuelfielder Samuel treat yourself, buy as larger receiver you can. It's not just the ease of cleaning but air tools are far more controllable and less bulky. 30 years ago the amateur could not afford to buy air tools they are now so cheap, plenty of torque, and as said so controllable. You could run the pipes neatly all around your workshop with quick release connections at strategic positions.
It's the correct oil Castrol Hyspin AWS68. It has ISO viscosity grade 68 which is like SAE 20W. This is actually a hydraulic oil. I've no idea why that is what Harrison specifies.
@@samuelfielder Thank you. I think it might be normal for that bearing to have not much oil getting to it. Seems that way from the surface rust on the keeper ring, like it has been that way for many years.
I guess the previous owners tried turning the speed dial knob when the lathe was still spinning, which made the pin shear off. Mine doesn't seem to have the 2 pins, although it does have the same notches.
And the reason you need more oil than the manual states is probably due to you doing a complete flush, not a drain. Like with a car, there's always some oil left in the engine.
You washed it with kerosene and it went down the headstock oil feed holes, you should really have blown them out to get the kerosene out and then put the oil down there.. I have an L5 but the book states it should e lubricated with liquid unobtainium ,😊so what I need to know is what is the best Modern obtainable oil should I use to fill it.
If you want to preserve them, knock them out from the inside. They're a push fit. If you don't care because you're going to replace them anyway, gouge a screwdriver into them from the front and lever them out.
![24 ชั่วโมง ซื้อของสีเดียว!! [Ver.2024]](http://i.ytimg.com/vi/TNPgzIMr_w8/mqdefault.jpg)
Another very interesting and watchable episode in this fine series. Thank you for sharing. 👏👏👍😀
I was getting chatter when facing 6" dia steel loco-wheels on an ancient Colchester student 1200. Judicious use of a pry-bar between the back of the chuck and the gearbox face showed 5 thou end-float, so off with the top cover and have a look. The headstock shaft bearing-adjustment locking tab had lost an 'ear', allowing the castellated ring to work loose. I am only a hobby engineer, so it was hand- tightened it so it would still turn, then backed off to the nearest available locking tab, (like a car wheel bearing), but still turned freely with no detectable slack. I didn't wash the box out, as I didn't want to get bits in the rollers and trash them. The box oil was very low, so I topped it up to half a glass with hydraulic oil (straight 32) from a local machine shop that keeps bulk for their own lathes.
I think your right them rollers don’t look right. Max grant swan valley machine shop as just done a series of videos replacing headstock bearings he made sure they were all turning. He definitely knows what he’s doing. We have that same machine at work and that tapered pin that broke are roll pins in ares (don’t know for sure if they are original but I think so ) this series of videos you have done as been really interesting and helpful. Thanks very much for for taking the time to make them all the best I’m sure you we’ll get it sorted 👍👍👍
Thanks, I'll have a look at Max. I see he has an interesting way of testing to see if all the roillers in the bearing are rotating.
More good progress Samuel, always an interesting watch, I did notice the rollers moving , you would think with only 0.002 mm endfloat they would be held captive. There is a guy on youtube Haxby Shed with a Harrison 140 lathe, he has covered the lubrication of the headstock among other interesting stuff, although not the same model as yours, it has some similarities, cheers Dave
Thanks. I have watched Haxby Shed in the past but hadn't noticed his work on headstock oil pumps. It seems he found exactly the same "problem" that I noticed: oil not being splashed upwards enough (at any rate using the gear ratio that allows me to drive the spindle with my electric drill).
Samuel. Just a thought and not having the advantage of handling the spindle assembly and looking at the preload arrangement, these taper bearings being back to back I would guess the 2 micron end float ensures the rollers are not actually loaded in the free state, being such a precise assembly the rollers would perhaps 'roll' ensuring lubrication. Also when the main spindle is under load and expansion takes place would this increase or decrease the end float?
Three bond 1215 is a fantastic jointing compound. Might be worth a go.
Thanks. I think that's a good silicone RTV sealant. But in the end a new joint washer sealed ok anyway.
Another thorough job and a pleasure to watch. Just a point of interest. I rarely see you use an airline and have no doubt you have a compressor, as I cannot work without an airline can you comment?
No, I don't have a compressor yet. Just use air cans at £20 a pop.
@@samuelfielder Samuel treat yourself, buy as larger receiver you can. It's not just the ease of cleaning but air tools are far more controllable and less bulky. 30 years ago the amateur could not afford to buy air tools they are now so cheap, plenty of torque, and as said so controllable. You could run the pipes neatly all around your workshop with quick release connections at strategic positions.
Not sure what to make of the rollers, but if it is in spec that's a 👍
The gear oil looks very fine? Is that the correct viscosity?
It's the correct oil Castrol Hyspin AWS68. It has ISO viscosity grade 68 which is like SAE 20W. This is actually a hydraulic oil. I've no idea why that is what Harrison specifies.
@@samuelfielder Thank you.
I think it might be normal for that bearing to have not much oil getting to it. Seems that way from the surface rust on the keeper ring, like it has been that way for many years.
It's pre-load not actual load so I'd imagine them rolling back is a good thing.. you also need to take into account the bearings warming up.
I guess the previous owners tried turning the speed dial knob when the lathe was still spinning, which made the pin shear off. Mine doesn't seem to have the 2 pins, although it does have the same notches.
And the reason you need more oil than the manual states is probably due to you doing a complete flush, not a drain. Like with a car, there's always some oil left in the engine.
You washed it with kerosene and it went down the headstock oil feed holes, you should really have blown them out to get the kerosene out and then put the oil down there.. I have an L5 but the book states it should e lubricated with liquid unobtainium ,😊so what I need to know is what is the best Modern obtainable oil should I use to fill it.
I don't know. M300 specifies Castrol Hyspin AWS68 which is obtainable. This is actually a hydraulic oil. No idea why it is so specified.
Hi Samuel whats the technique to remove the oil sight glasses?
If you want to preserve them, knock them out from the inside. They're a push fit. If you don't care because you're going to replace them anyway, gouge a screwdriver into them from the front and lever them out.