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Nick_G03/05/2016 14:18:00
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1808 forum posts
744 photos

.

No prizes for guessing what. sad

Wish me luck.!!! laugh

Nick

JasonB03/05/2016 14:34:17
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Moderator
22017 forum posts
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That's the problem with these clapped out second hand machinessmile p

David Colwill03/05/2016 15:54:32
774 forum posts
40 photos

Make sure that you follow modern practices and pack them with casting sand and greasesmile p

Roger Williams 203/05/2016 17:20:34
340 forum posts
1 photos

At least youve got a decent exploded drawing for reference !. Good luck to you anyway.

KWIL03/05/2016 19:02:06
3477 forum posts
66 photos

I hope the spindle to bearing inner fit is kind to you or else you may need to make a puller to extract the spindle. Don't ask.

Nick_G03/05/2016 21:28:55
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1808 forum posts
744 photos

.

Hi again guy's

Jason although his remark was said in half jest he actually does have a valid point.

I will go into the reasons of my bearings not being tops tomorrow. But there are considerations to be made that at first may not be totally obvious when buying a second hand machine.

I have had a few issues with my lathe but at the price I paid for it I have no complaints and I am still glad I purchased it. - Buying 2nd hand 'English iron' will so long as it's a good one give one a better machine that is nicer to use no doubt about it.! But then if a 'new for new' comparison was made regarding price it is a one horse race and we are not comparing like for like. - But having said that I nipped into Axminster over the weekend as I was passing and their lathes for what they are (IMHO) are awful, raw, crude and overpriced. - But that seems to be small beer when such a machine is in the skilled hands of many upon this site. smiley

Other considerations are for e.g. Mine (as a lot of second hand machines) came without the following :-

a) A full set of change gears. OK it has a gearbox and many threads can be cut without them. But I still really need some. These are available still from Boxford but at top dollar. ........ They seldom come up on ebay.
b) Spindle bore reducer. ........... Silly money from Boxford.
c) Fixed and travelling steadies. Again big coins and I have never seen 2nd hand ones.

The above should I think be mentioned when advice is given to 'newbies' requesting information on what machine to buy to get started with. But as I said I am personally glad I bought the machine I did. But that is just me. smiley

To be continued. .............................................

Nick

Michael Gilligan03/05/2016 23:07:31
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19601 forum posts
997 photos

Wise words, Nick star

MichaelG.

Nick_G04/05/2016 11:07:01
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1808 forum posts
744 photos

.

Morning. smiley

I have for some time had on and off concerns about the headstock bearings. These were first raised a good while ago when noticing that a previous owner (was a school) must have had a play with the adjustment. This was apparent as the adjusting lock nut is meant to be moved with a hook spanner. But I could see that somebody had been using a drift due to indentations in it. The rest of the lathe has virtually no wear upon any surfaces and was just grubby when purchased so I cannot think why anyone would feel the need to play with the bearings. - Some may remember that I had to also replace a cracked plate that the topslide sits upon.

I have at times struggled to get consistent results. One cut would be fine and the next everything would go south. But mostly things would be OK and I would put down these sudden departures down to me having an off day and with some justification my lack of experience. - Things have been like this for some time now.

A while ago when doing an oil change I took the top off and noticed some very small metalic particles in the bottom. These were cleaned out and a magnet placed inside along with the fresh oil.

More recently I started to notice a few more tell tale signs of all not being well. When running at top speed upon starting there would be for half a second as the spindle hit speed a very slight rasping and rattle from the bearings. I was also getting banding and ribbing at all speeds. This became more so as the tool got closer to the chuck and away from the confines of the revolving center in the tailstock. ....... Alarm bell time.!! There was also a slight ticking sound starting to emerge at lower speeds. I would also perhaps make a straight cut and the next one without touching anything would possibly have a taper in it of a few thou.

I did at this point nip the bearings up. Things were slightly better but still not right and the noises continued. It was now that I took the lid off again and investigated for metal particles in the headstock sump. ............ Sure enough they were there (although small) all stuck happily to the magnet. sad - I had to face reality that I was going to have to put my hand in my pocket and spend some coins on new bearings.

The best price I could get them for was a company in France and they arrived within a few working days. Interestingly the same company also has a UK base but they wanted considerably more money for them.

The strip down commenced :-

The original rear bearing cup. Scratches and pickup marks can be seen on the original image but not sure if they are visible at web resolution. I would have taken more images had my hands not been covered in oil. Plus I kept forgetting. wink

The front bearing cup (which is the larger of the 2) Each bearing type has 2 designation numbers. One for the actual bearing and the other for the cup type. The 'B' on the cup denotes that it has a flange.

The spindle and the bearings removed. The bearings and the cups while not coming away from their mating parts too easily were not thankfully a major problem.

The new cups in their locations. - Keeping everything spotlessly clean now became paramount.

The old bearings.

The rear one seemed to be in worst condition to the front. But neither 'Looked' to be that drastic. However a notchiness could be felt in both of them.

I have now got the machine back together and it's the critical pre-load time. I did not have a hook spanner of the correct size but the one I have for adjusting my motorbike rear suspension fitted after it had taken a little trip to the grinder.

Cont ....................

Nick_G04/05/2016 11:08:00
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1808 forum posts
744 photos

.

Continued as word count was too high for single post.

I adjusted until there was no play visible upon a dial indicator placed between the headstock and spindle and ran at a low speed listening for 'issues' and gradually increased the speed to mid range. - I resisted actually cutting metal and putting any load on the new bearings until I am confident they are in 'the zone' But everything sounds sweeter and obviously smoother.

I am using the temperature method for final adjustment. What I am looking (or feeling) for is when the lathe has been running constantly for about 20 mins the area of the headstock is warm but certainly not hot.! Presently I have adjusted them a few times and got them running about the temp of ........... errrrr babies milk. So I will nip them a tad more and retest. This is time consuming no doubt about it. As you get closer the adjustments become far smaller. I imagine that the difference between just right and too much is very small. - I will probably run a few warming and cooling cycles to let the cups settle. Patience is the key I think.

I will report back later.

Nick

Michael Gilligan04/05/2016 11:35:22
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19601 forum posts
997 photos
Posted by Nick_G on 04/05/2016 11:07:01:

.

.

Nicely documented, Nick

It's certain to be a useful reference for anyone following the same path.

MichaelG.

...

Is the Stanley knife for wrist-slashing in the event of failure ? devil

... Hopefully you can put it away soon.

Nick_G04/05/2016 12:49:03
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1808 forum posts
744 photos
Posted by Michael Gilligan on 04/05/2016 11:35:22:

Is the Stanley knife for wrist-slashing in the event of failure ? devil

... Hopefully you can put it away soon.

.

laugh ........... The knife was to flick off the oil seal gasket. smiley

.

On closer inspection in daylight the bearing marking was evident.

And the cup.

Nick

Clive Hartland04/05/2016 14:24:19
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2759 forum posts
40 photos

Bear in mind that the gears are running in the same oil as the bearings. Any debri off the gears will always get in the bearings hence the wear pattern. It is amazing how much wear comes off the metal gears.

Perhaps you need to fit/put in a magnet to pick up ferrous debri from the gears to help stop transfer to the bearings. A method is to drill a hole to suit the diameter of a round magnet and insert it in a suitable safe place with araldite.

Clive

Swarf, Mostly!04/05/2016 15:05:10
623 forum posts
67 photos

Hi there, Nick and Clive,

When I had a BMC Mini I bought a replacement sump plug fitted with a magnet. They might still be available - try your local 'go faster' shop.

Best regards,

Swarf, Mostly!

Nick_G04/05/2016 15:52:32
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1808 forum posts
744 photos

.

Thanks guy's,

There is a magnet in there. It says so in my 3rd post. yes

But cheers anyway. smiley

Nick

Clive Hartland04/05/2016 17:17:56
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2759 forum posts
40 photos

Nick, did you see the magnet festooned with particles ?

Clive

KWIL04/05/2016 19:59:46
3477 forum posts
66 photos

When setting up the bearings, some lathe makers specify a loading setting usually checked with a piece of string around a chuck and a spring balance (at the correct temperature).

Edited By KWIL on 04/05/2016 20:00:12

Swarf, Mostly!04/05/2016 20:14:46
623 forum posts
67 photos
Posted by Nick_G on 04/05/2016 15:52:32:

.Thanks guy's,
There is a magnet in there. It says so in my 3rd post. yes
But cheers anyway. smiley

Nick

Yes, I saw that, but you didn't say whereabouts the magnet is situated. I posted in haste so, I'm afraid, I didn't make my point clearly enough! It was that having the magnet on the drain plug is advantageous.

Best regards,

Swarf, Mostly!

Neil Wyatt04/05/2016 22:50:53
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Moderator
18899 forum posts
734 photos
80 articles

> The best price I could get them for was a company in France and they arrived within a few working days. Interestingly the same company also has a UK base but they wanted considerably more money for them.

Possibly because British Timken bearings are now made in France? The ones I have were, at least!

Neil

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