Harrison M300 lathe - buggering with the headstock

[@andrewdolinskiatcarpathian]

This series continues to educate, inform and entertain. Despite your trials and tribulations, and undoubted pain at times, you continue to make great progress and In doing so you are providing us with great content. Thank you Samuel. All the best, Andrew 👏👏👍😀

[@AmiPurple]

Found your KZbin channel recently, been watching your videos, I find them enjoyable and entertaining and lovely to watch, thank you making and putting the videos on KZbin.

[@tom87112]

I looked everywhere for info on how to remove my M300 spindle and here it is! Thank you sir!

[@howardosborne8647]

Hi,Samuel. The poor oil circulation to the front bearing is also a common weakness on other models of Harrison lathes. The L5A,L6.and 140 all have poor oil delivery to that front bearing at prolonged lower spindle speeds. I didn't know that Haxby shed had added an oil pump,I must have a look at that video. Don't worry too much about the bearing rollers not being replaced in exactly the same relative locations in the cage. They are size matched for closely matched diameters when assembled at the factory. The indexed positions in the cage are not of any real importance and if they ran concentric before you dismantled them then they should run just as concentric after reassembly. Another thing that may interest you to know is that the earlier L6 Harrisons were fitted with plain Timken taper bearings with solid rollers. These solid roller type Timkens are a fraction of the purchase price than the Gamet ultra precision bearings you have here. I have never had any spindle runout problems with the solid Timkens in my L6 and do wonder whether fitting the solid type rather than Gamet would be noticed in accuracy terms by any homeshop machinist. The best way to deal with removing the rear spindle bearing is simply to carefully drive the spindle out towards the front and it will slide through the rear bearing. That is how I have always done it on the L6 lathe.

[@stevechambers9166]

Your doing a good job I and a lot of others are learning a lot from you It’s hard enough doing the job never mind filming it as well many thanks👍👍👍👍

[@carlwilson1772]

Hello Samuel. That was a very informative film. I hope you will not mind my making a small joke at your expense. I have a book called "Technology of Machine Tool Maintenance" by Dr. Ir. C. de Beer, of the Eindhoven University of Technology. In the first paragraph of this work he states "machine tools generally suffer more from maintenance than from use". I often think that is the case! Anyway, all joking apart, your disassembly of the spindle and bearings thereof has been highly informative for me. I am subscribed to a channel called Haxby Shed, run by a gentleman named Paul. He has a Harrison 140 lathe, mechanically similar to the M300 in many regards. He did an experiment using a clear lid for the headstock gearbox. This proved that the splash lubrication system was inefficient through a surprising range of rpm settings, leading to bearing oil starvation. He has alleviated this on his machine by fitting a small motor driven pump. I hsve been following his work carefully and I have an idea to fit a small gear pump, driven from the main electric motor. This is done in the larger M series machines. The discovery of spalling on your headstock front bearing outer race would seem to add weight to all of this. So thank you for what has been a great contribution to the ongoing store of knowledge about these machines.

[@samuelfielder]

Thanks. I also watch Haxby Shed and he did a good job with that oil pump.

[@carlwilson1772]

@@samuelfielder Yes he did. And I think that the spalling found on your spindle bearing race supports his original conclusion and further vindicates his decision to fit the oil pump.

[@daveharriman2756]

Thanks for showing this series Samuel, it's absolutely fascinating, and showing all your "mistakes",makes it even more interesting, you could have easily edited them out. I did think, after seeing the slight wear in the front bearing that there is definately a link with your last video, where you alluded to the possible lack of lubrication, this would be a reletavely simple task to rig up an external feed, to arrest any further deterioration of the bearing surface. just a note on circlips, they being stamped out, have a sharp flat side and a rounded side, if they were originally installed the wrong way, i.e. the rounded side frontways, you would have a harder time getting your circlip pliers to stay in the holes. ......and don't forget, historically, many of the great engineers were left handed! anyway, best of luck in this project, cheers Dave ps, I think the back bearing will be fine, and certainly, you won't alter the original spec. by reassembling it

[@samuelfielder]

Funnily enough Haxby_Shed made a headstock oil pump for his Harrison 140, which is basically the predecessor of the M300, so it might be a systemic design problem. See kzbin.info/aero/PLr7TZ6sBK_mq-9_IgPulV2VjPQ03uACn2 . Good point about circlip holes - I must get then the corfrect way around when I reinstall.

[@daveharriman2756]

@@samuelfielder Yes, I've seen that vid, I was thinking some kind of mechanical pump, with supply/syphon from the sump in the headstock. driven by one of the gears in there.

[@juddhadley8778]

Big respect to you Samuel, many would of given up but your persevering. There's a clip on KZbin were its demonstrated that oil doesn't get to the bearings if the lathe is run slowly, possibly its the one described below.

[@Bg_Anipar]

Have you dissambly gearbox spindle?

[@timothysfather5496]

Your pain is our gain.... for that I thank you

[@tom87112]

At the 3:57 mark it shows a loose wire clip dangling on the spindle that I think was attached to the inner bearing. Does that also have to come off ? I'm not talking about the circlip that retains the gear.

[@samuelfielder]

That is a yellowish plastic ring. It should have been attached to the back of the inner race of the rear spindle bearing, but had come loose. It is shown in its correct position on the bearing at 27:31. Yours should still be attached to the inner race and will come off when you remove that. That plastic ring needs to stay in place otherwise the rollers will likely fall out of the bearing if you take the cage off the inner race. That's what happened to me!

[@ianlulham]

Could that be chatter on the front bearing. The cutting tool would push the bearing load towards the rear of the lathe leaving the front half of the bearing with more play. Has this allowed the front of the bearing to hammer the marks in the ring.

[@samuelfielder]

It's possible, but I don't know how I'd tell. Tending against that is the fact that the spindle end float was at the low end of the specified range.

[@darrylshelford2674]

Hi Samuel, The front bearing marks look like bearing chatter, either from when working due to the bearing preloaded not quite right or and I'm leading more to this, from travel. If the preloaded is not set correctly when the bearings are new and the lathe is transported a long distance from the factor they can chatted (sometimes they chatter anyway) and mark the inner and outer cup and cone. Don't worry we have all been down the road of, "IF ONLY".

[@samuelfielder]

Thanks. Is this the same as "false brinelling"? I thought it would match the spacing of the rollers.

[@darrylshelford2674]

@@samuelfielder Usually there is only one set of marks, however if you watch any shaft that is affected by vibration it usually turns. Given the angle of the normal wear pattern in the bearing cup it could just be from the flex of the head stock shaft which would be up and away from the tool, not just 90 degrees from the tool. I watched a great video about lathes and how they where in ships, how a ship rocks and rolls as well as it twists, yet all there parts were machined to a high standard. Sometimes I think we over think things, it's the same old saying "KISS" Keep It Simple Silly. Keep up the good work.

[@darrylshelford2674]

Hi again Samuel, I forgot to mention that on the shaft that you are replacing the seal on, I was always told to emery paper the seal running area as it makes the seal seat in property, emery around the shaft not along the shaft and lube the shaft when reassembling.

[@erickvond6825]

Mistakes are amazing things if we learn from them and it sounds as if you have. So if it's a lesson well learnt then is it really a waste of time? I think if I had one of those I'd be fafing about with it likely the same as you. Have fun with it lad, that's all that matters.

[@Bg_Anipar]

Please help me repair my m300 lathe like your video.

[@samuelfielder]

You could also view kzbin.info/www/bejne/fHjUgJWkrJycqpo and parts of kzbin.info/www/bejne/f5jEaaufd5mbetk . And the video by Max Grant I linked to kzbin.info/www/bejne/r5e4d6iGo8l6ers . Let me know if you have any questions. Best advice is don't mess with the spindle unless you have to. I am not an expert!

[@neillawson4493]

I'm not convinced you could have removed the seal without removing the shaft. If you look back over your footage it seems to me you would not have been able to get enough leverage on the rigid seal. Maybe you could have drilled it to break it into pieces but you risk slipping and damaging the seal running surface. So don't be downhearted you were probably destined to remove the spindle.

[@howardosborne8647]

The best method is to drill a couple of small holes in the face of the old seal then screw in a couple of self tapping screws to either use a lever to prize against the screw head and lever the seal out or use a small slide hammer to pull on the screw heads.

[@wizrom3046]

ONE drop of oil after sitting for SEVEN days? Wow I can tell you never owned a Harley haha. You measure the oil leak by inches diameter of the oil puddle under the bike after sitting overnight. Less than 4 inches is fine. >8 inches means time for a new oil seal. 😎 Sorry about your front bearing. Possibly could be under oiling like you said. In the old Harley gearboxes they have a thing called an "oil slinger" that is a wheel on the shaft inside the grearbox, the slinger wheel has big teeth that throws a heap of oil around inside the gearbox when the shaft is spinning. Maybe your gearbox is missing a part? Or maybe you could add a slinger? Just an idea.

[@samuelfielder]

Thanks. A slinger would certainly be much simpler than rigging up some kind of oil pump. Worth looking into.

[@romandybala]

You know what is a giveaway? A crpenter's hammer instead of an engineers hammer. Fail.

[@samuelfielder]

I am a physicist, not an engineer. Given I'm using a copper drift, I don't think it matters what kind of hammer I'm using. You might try to be kinder when commenting on other people's videos. I see you have none yourself.

[@chilebike6556]

@@samuelfielder I'm with you, SF. I like your dry humour.

[@chilebike6556]

Sam, probably like you I don't have a heavy engineering hammer, my work doesn't reqire hammering. But soft, could you have extracted the spindle by removing the gear circlip and using some allthread through the spindle with a sleeve to pull the spindle out forwards? I did wince at the thing being hit with the hammer. My colleague bought a new M300, made in Taiwan, a world of pain with that. 12k, very unimpressed, Harrison not interested. Tight bearings, leadscrew problems, gear selection problems. Not good. You have got me concerned about my own M300 bearings now, but what the eye doesn't see...