What lathe do I need?

[RSalles]

Gentlemen,

Coming in a hurry from another thread: does anybody have an idea of what size or type of lathe do I need to make myself any size of flange and retaining rings for lenses in barrel and shutters?
I have zero experience with mechanical lathes but have worked a bit with wood lathes, and maybe I can talk with some people in my town to have a crash-course, just to get started and go ahead by myself from there,


Thank you,

Renato

[jp]

You will want a lathe with a big enough 3-jaw chuck to hold the piece of round metal you are making a flange/ring from. Most of them are reversible for extra room. It will also be important for the lathe to be able to cut the threads you'll want. Most of them have spec sheets telling which thread pitches they are built to provide. The lathe will move the tool at a speed necessary to cut a thread pitch via a separate but connected shaft and gears for that purpose. They are not tough to learn, do get a couple hours of help from someone. Safety concerns should be similar to the wood lathe.

[R.K]

And the lathe must be able to cut metric treads, because most of those treads are metric.

[Jac@stafford.net]

This does not answer your question, but have you considered a universal mount?

From a Finish member - link.

New versions are being made again.

[Jim C.]

Metal Lathe choice is a matter of what you can afford and space, and the largest size flange you anticipate in making.
Threaded flanges for barrel lenses can vary from 2 inch to 5 inches or more.
Google for threading on a lathe, lots of info out there.

You should also consider a four jaw lathe chuck instead of a three jaw, the four jaw will grip round and square material
I use mine to bore out lens boards.

[imagedowser]

Jim's right.... but get both for your machine, it doesn't have to be three jaw or four..... try to find a good used lathe with everything your likely to need, like tool rests, etc,etc. or it will nickle and dime you to death.

[Jim Jones]

My old 6" lathe is big enough for most camera work, and can cut both metric and English threads. A three-jaw chuck is a convenience: the common four-jaw chuck will suffice.

[Jim C.]

Jim's right.... but get both for your machine, it doesn't have to be three jaw or four..... try to find a good used lathe with everything your likely to need, like tool rests, etc,etc. or it will nickle and dime you to death.

Or drive you crazy trying to find factory only specific parts.
imagedowser has a good point, my lathe is a Maximat7 rarest of the rare for OEM parts, the price for it was
get out or it goes in the trash kind, grabbed what I could that was listed in the manual,
it took me years to get a thread dial and a spare set of half nuts.
But I digress........

Considering you're in Brazil, you look into what's common in your area for lathes, you ay be able to get a complete used setup
for not much money and finding parts would be a lot easier.

[Peter Yeti]

Renato,

having a lathe - or rather a complete metal workshop - is a great asset for those of us who restore, repair, re-shutter, or mount vintage lenses. But it may not be economical to buy one unless you need it quite frequently. I inherited mine, coming from my grandfather's little tool shop, otherwise I wouldn't have one. Here is a link to it with details and pictures: http://www.lathes.co.uk/eisfeld/ There is hardly a thing one couldn't do with it, given you are a skilled craftsman.

The key feature for cutting threads is a spindle to drive the carriage and a sufficient set of change wheels (gears) to achieve the correct pitch. The pitches you come across in lenses are usually between 0.5 and 1.0 mm or the equivalent in tpi. Quite common ones are 0.5, 0.75, and 0.9mm but especially 19th century lenses can have very odd threads. A thread gauge is absolutely indispensable. It's also important that one can reduce the turning speed far enough or it will be a real challenge.

And there's one more thing you will need: a lot of time.

Peter

[Tracy Storer]

I have a Sieg C4, paid about $1300 for it 5 years ago, but additional tooling took it up another $500-$1000. It lives on its own bench, about 2'x4', the machine weighs around 250lbs.
This particular machine has a metric lead screw, but with the proper change gears, it is possible to cut metric and imperial / english threads. I have cut a lot of threads not listed on the threading chart, but it took awhile to wrap my head around calculating the gear trains.