Thread: Interesting Day

Capstans and turrets really are industrial relics. They usually sell for scrap value, or the value of any tooling in the lot. I have seen a number of auctions where no bid was forthcoming for these.

John,
Be gratefull it was diesel and not petrol
But, then again, it costs more

Hmm, I'd have like the lathe to replace my existing lathe.

Glad the fuel leak wasn't in my P38A - it would have burned quite well!

Ron

Gentlemen, you have my attention...

A lathe I know about a drill mill I know about

a capstan and a turret?

so far as I know the first is a bloody hard to find winch for a series that drives off the crank pully and the second is the thing on top of a tank that when pointed in your general direction means you are about to have a very bad day..

I realise from the general gist of the convo that thats not what you are talking about... my question...

What the hell are you talking about?

Originally Posted by Blknight.aus

Gentlemen, you have my attention...

........

What the hell are you talking about?

Capstan lathe; a lathe with a rotating tool holder
Turret lathe; = capstan lathe (courtesy SOED)

They are types of lathe with a method of bringing a variety of different tools into exact position to carry out tasks that have been previously set up (by rotation, hence the "capstan" or "turret". In the past extensively used for mass production - this is now usually done by NC machines, so they are virtually obsolete for mass production and less suited to the home or workshop user than lathes specifically designed for this. Since they are usually big, heavy, need three phase power, and often well worn, the demand for them is pretty low.
At the same sale a well worn "Hercus" 20" lathe attracted spirited competition and went for $800 - approaching the price new of similar Chinese lathes.
John

I assume you mean one of those funky lathes where the actual job stands still and the tool holder works around the piece for doing things where you need to machine a protrusion on something else that you just cant physically rotate...

Imagine say the output shaft on a rover transfer case that had to have a a seal faced resleved but for whatever reason you couldnt dismantle the case, just remove it from the gearbox.

and the capstan one would be the one where the tool rotates traditional lathe style and turret where it goes round merry go round style....

Them Ive seen, Ive used my drill mill as a poor mans turret lathe once

Originally Posted by Blknight.aus

I assume you mean one of those funky lathes where the actual job stands still and the tool holder works around the piece for doing things where you need to machine a protrusion on something else that you just cant physically rotate...

Imagine say the output shaft on a rover transfer case that had to have a a seal faced resleved but for whatever reason you couldnt dismantle the case, just remove it from the gearbox.

and the capstan one would be the one where the tool rotates traditional lathe style and turret where it goes round merry go round style....

Them Ive seen, Ive used my drill mill as a poor mans turret lathe once

No. The tool is fixed while in use but there are several tools on a turret or capstan so that they can be rotated into position to carry out several turning jobs in succession on the same bit of metal. Useful for mass production, not very useful for one off jobs.

See for example http://www.oldengine.org/members/diesel/Ward/ward18.htm. This is not the actual one at the sale, but is similar.

Originally Posted by JDNSW

No. The tool is fixed while in use but there are several tools on a turret or capstan so that they can be rotated into position to carry out several turning jobs in succession on the same bit of metal. Useful for mass production, not very useful for one off jobs.

See for example http://www.oldengine.org/members/diesel/Ward/ward18.htm. This is not the actual one at the sale, but is similar.

Being a fitter & turner, and aware of the ready availability & low prices of machine tools and metal working equipment nowadays, one forgets there are people out there who don't know these things. I will try to flesh out JD's comments.

Capstan & turret lathes were developed in the latter half of the nineteenth century, initially in the USA. Historians differ, but generally opine that the first examples were from Brown & Sharp, or Pratt & Whitney.

Usage is in mass production or repetition work, rarely jobbing work.

Like engine lathes, they have a bed, headstock & spindle to which work holders attach, usually a cross slide and tool post(s), but not a tail stock, which is replaced by a hexagonal turret tool holder which can index to bring tools into play.

A capstan lathe is normally used for high volume production of small pieces, most commonly from bar stock fed from the outer end of the headstock by a bar feeder. A capstan's turret is mounted on a slide along which the turret can be moved, and a carriage which can also move on the slideways of the lathe bed, parallel to the bed's axis.

A cross slide with one or more toolposts mounts between the headstock & turret and functions in the way of tools on an engine lathe.

A turret lathe is used for heavier or larger diameter work, and is more suitable for long turning & boring operations. A turret is generally of much heavier and stronger construction than a capstan. A turret lathe's hexagonal turret is mounted to the carriage direct. This is stronger and more rigid than the capstan's arrangement thus enabling the heavier class of work. The turret lathe also has the cross slide and toolposts as per the capstan.

A huge range of tools and tooling were developed, some of which need to be seen in operation to be understood.

Their advantages in production work was in the machines' ability to quickly and accurately turn out identical workpieces & be operated by unskilled labour.

You may recall seing "Positions Vacant" ads for toolsetters. Toolsetters ground new tools, resharpened, mounted, changed tools in capstans & turrets and often maintained the machines. They were usually, but not always, tradesman machinists, often the only ones in the factory.

During WW2 Rolls-Royce built a new aero-engine factory in Glasgow and had instant industrial problems. The Scottish work practices were that ALL machine tools had to be operated by "time-served" men, even machines that had no trade skill requirement. This was negotiated down to an agreement that unskilled workers, including women and juniors could be machine operators until the cessation of hostilities, when the existing system would return.