# Perfect tailstock alignment!



## Mastermaker (Apr 10, 2011)

Having aligned my tailstock to the best of my ability I found that while the horizontal alignment is pretty much spot on, the tailstock is ever so slightly higher than the headstock.

Chronos sells morse taper finishing reamers, either with straight shanks or with a morse 2 shank.

My question is............

If I were to re-ream the tailstock on my lathe which would be my best bet for the best alignment?

A straight shank reamer held in a morse collet in the headstock or using the one with a mt2 shank with a mt3 to mt2 sleeve...?


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## mklotz (Apr 10, 2011)

Many lathes are sold with the TS slightly high to allow for wear over time.

A small vertical misalignment will have negligible effect on accuracy.

Put that reamer back in its holster.


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## Mastermaker (Apr 10, 2011)

Would that apply to chambering reamers as well???


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## pete (Apr 10, 2011)

No!!!! And to make a totally obvious statement, If your implying that reamers are reamers or being flipant, Then I'd suggest you back up and consider Marvs statement very carefully. He answered your question correctly. ANYTHING Marv posts you can take out a bank loan against. Furthermore, A generic thank you when someone takes the time to answer your question using years of experience probably wouldn't be considered excessive. 

Pete


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## steamer (Apr 10, 2011)

Let's keep it all civil guys OK....No need for pounding sand here.

Over the years lathes were often offered with the TS somewhat high to allow for wear.  Toolroom lathes were an exception, but they were expected to be better taken care of.

I would leave your TS high and as is.  If your chambering, and I know chambering reamers are touchy in this respect...though I know little of the gun smithing trade.  You could beg borrow or make a floating reamer holder for the super fussy jobs  making one wouldn't be that hard, and you could then get the shank to a fair the well if you so desired.....there's 47000 ways to skin the cat....at least 46000 work just fine and apply to this dimension of reality.

Dave


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## shred (Apr 12, 2011)

You will want a floating reamer holder for chambering reamers even if your tailstock is perfect. It's not a terribly difficult item to build should you so desire.


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## Mastermaker (Apr 13, 2011)

I am planing to make a floating reamer holder but the paranoid side of me just wants to remove as many variables as possible.

Anyone know which would be most likely to have the least runout, a morse shank MTreamer in a sleeve or a straight shank MTreamer in a MTcollet?

My money is on the collet so if no one knows then that is what I'll get.


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## krv3000 (Apr 14, 2011)

HI right this may help sum of you if you lathe is a more modern one ie with the lathe head bolted to the bed and not a one piece casting its possible to shim up the head to put it bang on center with the tale stock but as bin sed it dont mater if the tale stock is a bit high  regards  bob


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## New_Guy (Apr 14, 2011)

Mastermaker  said:
			
		

> I am planing to make a floating reamer holder but the paranoid side of me just wants to remove as many variables as possible.
> 
> Anyone know which would be most likely to have the least runout, a morse shank MTreamer in a sleeve or a straight shank MTreamer in a MTcollet?
> 
> My money is on the collet so if no one knows then that is what I'll get.



If you lower your TS now then you will need to fix it when it wears down

Your TS is fine it wont affect reaming operations most tools will have more flex than your TS miss alignment


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## Mastermaker (Apr 14, 2011)

The tailstock is 0.05(mm) to high, which in my eyes is rather a lot.


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## SignalFailure (Apr 14, 2011)

;D I wish 0.05mm was a lot to my eyes, I seem to have trouble seeing anything finer than an inch these days :big:


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## steamer (Apr 14, 2011)

Connelly, in his book " Machine Tool Reconditioning" lists the specification for engine lathes from 12" to 18" swing to have an error of 0.000 to .001" high. Never low.

On Toolrom lathes, the specification is 0.000 to 0.0008" high never low

Inches that is

Your not off by much. Can you scrape?

Dave


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## Swede (Apr 17, 2011)

I'm thinking it's unlikely a reamer is going to take additional material off of the tailstock bore so as to fix misalignment. Reamers, especially MT reamers, tend to strongly self-center.

Mount your straight-shank reamer in the headstock of your lathe, and apply an indicator to the shank closest to the flutes. I'll bet you'll see a TIR close to 0.05mm. No collet is perfect, and the long reamer shank will amplify the error. Chucking reamers have those long shanks for a reason, they flex and self center to finish off a hole.

I'd leave it be as well. Tailstock alignment (as a critical measurement) is over-hyped, IMO. Good luck with it!


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