Vic, hard to answer without knowing which one/size, etc, but… When I bought my lathe 10-12 years ago, I also bought an MT3 live centre, approx A$60 – 70 as I recall. It was a piece of crap, got graunchy very rapidly, had it replaced, same happened again, jumped up and down, they finally replaced it with a significantly more expensive Skoda, which still runs smoothly to this day.. I pulled the old Chinese one apart (just needed a standard pin spanner at the front) and all the internals came out as a single assembly. Thing is, the centre, which is the front end of the central shaft on which all the bearings are assembled, simply had an upset boss at the rear end which held everything together and simultaneously preloaded (overloaded) the thrust bearing.

The two main ball bearings feel perfectly ok (as they should, because it only had a few hours of use before the thrust bearing quit), but with the amount of work that you would have to put into it to try and make a decent device, the expression involving silk purses and sow's ears definitely comes to mind. I would suggest saving a few more quid and buying a Skoda, which I expect would also have other points available.

The only reason I have held on to my old Chinese unit is because (1) I rarely throw anything away, and (2), the MT3 shank and body might one day turn into a tailstock die-holder (if I wait long enough).

Roger

Thumbs up on the Skoda centres, I'm on my second one, the work I was doing on the first one over loaded things a bit, and although the parts were available, it was cheaper to buy a new one, $NZ 120 or there abouts.

Ian S C

Apologies, Vic, for going slightly off-topic, but

I just found this page about Parfetta centres; and I'm bewildered.

Look at the cutaway view … Can someone please explain why the Taper Roller Bearing is used back-to-front

MichaelG.

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Good thinking, Ian … but: so far as I can see [from the slightly better resolution image here], it's a little lacking in the 'threaded' feature  

The construction of my Gepy centres is more intuitively 'right'.

MichaelG.

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Edit: Just had another look … yes, that front seal probably is setting preload 

Edited By Michael Gilligan on 30/01/2016 22:06:53

Sparey in his book The Amateur's Lathe has the plans for building your own running centre, this would be good for light service. I built a number of these early in my time of owning a lathe, and sold them for use on wood lathes, as suitable centres were not available at the time.

Ian S C