turning long small diameters

[Speedy Builder5Participant @speedybuilder5]

Farm Boy again.  Making the valves.  3/8 dia valve head with 1/8″ dia x 1.4″ long stem in stainless.

Lathe:- Boxford 9″ dia

I have some stainless which turns OK but trying to turn the long stem as the workpiece flexes is giving unacceptable run out.  Do you step turn say 1/2″ to diameter plus 0.001″ then turn the next 1/2″ until required length, then burnish with emery cloth?

I think 1/8″ is too small for travelling steady.

Ideas please.

Bob

[JasonBModerator @jasonb]

I just use a BS 0 ctr drill and put a very small hole in the end so I can turn valve stems between ctrs. Never had a problem with them not sealing. Use 303 stainless

[IanTParticipant @iant]

In the past I’ve drilled a small bushing held in my tailstock drill chuck to the materials diameter and used that to support the material…a form of between centres turning.  I also have a tool-holder with a ‘guide’ that can be drilled to the (un-machined) diameter of the piece and where the cut happens as the metal is fed through. Can’t recall ever using it though. Seemed useful when I purchased it!  🙂

IanT

[Speedy Builder5Participant @speedybuilder5]

Thanks for the ideas gents.

Bob

[DalboyParticipant @dalboy]

I turned mine a little at a time they seem OK. Or you could do as Andrew Whale did and make it in two parts

See THIS

[bernard towersParticipant @bernardtowers37738]

small dia turning tool, easy to make

[Author]

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