Super 7 tailstock oddity?

[Philip RoweParticipant @philiprowe13116]

A while back I replaced the anti rotation key on the barrel of my S7 tailstock, the old one was very worn and had allowed the barrel to vibrate quite badly when drilling. Anyway, after replacement I was amazed at how this had transformed the operation of the tailstock but now I get all sorts of strange squelching noises when I wind the barrel back into the body, presumably the lubricating oil is being compressed and the noises are the result.

If I wind the barrel back with one of the oilers on the top of the body removed there is no noise, as its so long since the lathe was new (circa 1973) I really don't remember if it did it then.

Clearly its not a problem that needs any resolution but I am curious if perhaps anyone else here has come across this curiosity?

Phil

[Philip RoweParticipant @philiprowe13116]

[Brian OldfordParticipant @brianoldford70365]

I replaced the same component on my clunker of a Mk1 S7 a few months ago. I agree, it changed the drilling experience completely. Fortunately I haven't experienced any similar problems to yourself. Is there any evidence of the oiler binding on the tail-stock barrel? The other thing that comes to mind; if your new key had a small pip of material that you haven't filed off completely. My one had just such a pip but I removed it before I fitted the new key.

[Clive FosterParticipant @clivefoster55965]

Think the tailstock bore is supposed to breathe through the thrust bearing assembly as the barrel moves back and forth. No significant clearances anywhere so it doesn't take much to stop free breathing leading to noises off as the air squeezes through once sufficient pressure differential has built up. If undertaking a repair job like yours, especially on something essentially untouched for many years, its best to do a proper strip, clean-up, lubricate and re-assemble service. Old oil varnish does build up given time.

You may well get another pleasant surprise over how much the movement has improved. Like I did with my Smart & Brown 1024 which I'd have sworn was pretty good before clean up. Guess the deterioration creeps up on you over the years so you don't really notice how bad things have gotten.

Clive.

[Brian WoodParticipant @brianwood45127]

Philip and Brian,

​I have not replaced the key or anything else on my tailstock and that too makes happy oil squirting noises on being wound back to eject the tooling. There is nothing wrong in my view and it will drill 3/4 inch diameter holes, and larger, in steel bar without any complaint at all, having suitably piloted the hole first of course.

​It has done this since I bought it second hand over ten years ago. Maybe I use a heavier grade of oil than you do at W20-50, it is used all over the lathe too without apparent detriment.

Regards
Brian

[Philip RoweParticipant @philiprowe13116]

This afternoon I decided to try Clive's suggestion about old oil gumming up. I think things are now a little easier on the operation of the tailstock but the squelching/squirt noises are now worse to the point that I can feel additional resistance on the hand wheel when winding the barrel back into the body.

To cut a long story short I eventually found that if I remove the middle oiler on top of the tailstock and cover the hole with my finger I can get a significant pop if I wind the the barrel back in fast enough, like a cork out of a bottle. With my finger removed the barrel moves without any noises, so it would appear to be that everything is quite close fitting and the air is indeed being compressed and squeezing past the oil to make the noises.

Thanks to all for your input and ideas.

Incidently whilst I was doing this I was referring to the Myford handbook and inside was a price list for Myford lathes when my father ordered it in 1972, a Super 7 with Norton gearbox and the basic tooling as supplied less motor -£274!

Phil

[Clive FosterParticipant @clivefoster55965]

Phil

Clearances small enough to impede breathing indicate very little wear. A happy state of affairs which makes it well worth putting up with odd noises off methinks.

1972 Myford cost was 6 months salary. No wonder I couldn't afford one. Fast forward to 2002 and my Smart & Brown 1024 VSL cost me half of one months salary. No wonder I bought it. Wallet came out so fast it was smoking!

Clive.

[Nigel BennettParticipant @nigelbennett69913]

My Boxford 280 tailstock also makes squelching noises.

I guess we're all treating our lathes properly by lubricating them.

[Brian OldfordParticipant @brianoldford70365]

Posted by Nigel Bennett on 29/11/2016 17:17:51:

My Boxford 280 tailstock also makes squelching noises.

I guess we're all treating our lathes properly by lubricating them.

Oh dear! Does that mean I've been neglecting mine?

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