small metal lathe

[LuciferMutt]

Originally Posted by P B G

Here's my take on this.

Thread Cutting being mentioned I would determine if you need metric or not on those threads - Metric can be... Problematic - Not to the point of impossiblity, but the older American Lathes that are so common/available/awesome are usually best suited for cutting standard threads.

Which brings you to features - The minute you say threads/Lathes in one sentance you are talking about a lathe equipped with a leadscrew, and gear box. As well as a threading dial. Those features are required. If you want to thread often you should look for a quick change gear box instead of a swap gear varient.



The quick change gear box lets you select threads rapidly.


Other than that I would be looking for the following as must haves.

Chuck - 3 jaw
Face Plate
Tail Stock
Powerfeeds - on the cross slide if possible, but atleast on the carriage.

As optionals that will save you lots of money later -
Tool Post quick change - Aloris or similar.
Centers - for headstock and tailstock
Chuck 4 Jaw
Collets for headstock and draw bar for same.


Which brings me to what to buy/age. You'll need to put a number on how large of parts you want to work with, lathes have a number like 6" 10" or 12", which represents how large of an object can be swung. Also look for how long you want to be able to work - some lathes are 3' beds, some 6' - bear in mind that this number is the length of the bed, the part it can turn may be far shorter if you need to use the tailstock to support the end, or a drill in the tail stock, or if it cannot fit through the throughbore on the headstock of the lathe - which is another good thing to identify.

Age - Older to me is better so long as it is good condition.

http://www.lathes.co.uk/page21.html

http://www.lathes.co.uk/latheparts/


Personally I would be buying a Southbend - I would want it to be in good shape, with lots of extra goodies. Having a south bend and an atlas, I would go for a worse shape SB over a better shape atlas, it just has far better features.

Great post. I think you missed the OP's budget though. He won't even get a beat-up Southbend WITHOUT all that tooling for $500-$1000.

I disagree about a faceplate being a "must have" for his intended purposes though. I use faceplates maybe a few times a year and I do purely prototype work. Plus, if he wanted to, he could make some small ones that are held in the 3 jaw.

I'd say he needs a 3-jaw, a set of cheapy collets and whatever hardware is necessary to use those collets on his machine.

To the OP...lathes are among the more dangerous machine tools. Make SURE you understand what not to do before you start "messing around with it." NEVER LEAVE THE CHHUCK HANDLE/T HANDLE IN THE CHUCK! EVER! Make it a habit to use it and remove it immediately. When I was in trade school, the instructors duct taped the T-handles to the hands of those unfortunate students who ignored this rule Be very wary about dangly clothes, long hair, rings, watches, etc -- anything that can get pulled into the chuck or rotating feed shafts or leadscrew on the front of the machine.

Single point thread cutting takes quite a while to get proficient at and create a smooth functional thread that is actually the correct pitch diameter. You may well be better off with taps and dies and the tooling to hold them/align them to the tailstock.

[P B G]

I got my Atlas for free... So I think it just takes patience and putting out the feelers.

[Rafiki]

Originally Posted by P B G

Here's my take on this.

Thread Cutting being mentioned I would determine if you need metric or not on those threads - Metric can be... Problematic - Not to the point of impossiblity, but the older American Lathes that are so common/available/awesome are usually best suited for cutting standard threads.

Which brings you to features - The minute you say threads/Lathes in one sentance you are talking about a lathe equipped with a leadscrew, and gear box. As well as a threading dial. Those features are required. If you want to thread often you should look for a quick change gear box instead of a swap gear varient.


The quick change gear box lets you select threads rapidly.


Other than that I would be looking for the following as must haves.

Chuck - 3 jaw
Face Plate
Tail Stock
Powerfeeds - on the cross slide if possible, but atleast on the carriage.

As optionals that will save you lots of money later -
Tool Post quick change - Aloris or similar.
Centers - for headstock and tailstock
Chuck 4 Jaw
Collets for headstock and draw bar for same.


Which brings me to what to buy/age. You'll need to put a number on how large of parts you want to work with, lathes have a number like 6" 10" or 12", which represents how large of an object can be swung. Also look for how long you want to be able to work - some lathes are 3' beds, some 6' - bear in mind that this number is the length of the bed, the part it can turn may be far shorter if you need to use the tailstock to support the end, or a drill in the tail stock, or if it cannot fit through the throughbore on the headstock of the lathe - which is another good thing to identify.

Age - Older to me is better so long as it is good condition.

http://www.lathes.co.uk/page21.html

http://www.lathes.co.uk/latheparts/


Personally I would be buying a Southbend - I would want it to be in good shape, with lots of extra goodies. Having a south bend and an atlas, I would go for a worse shape SB over a better shape atlas, it just has far better features.

Agree completely.

Originally Posted by P B G

While I agree - particularly for common threads where you'd like to own the tap and die - and when you can use the center to get things started.

Those abnormal and large threads have dies and taps that cost as much as an old southbend lathe! Same with ACME threads and such.

1" dies 40$, 1.5" 100, 2" -400. And so forth.

holycrap yes.

I just picked up a 10"x 36" south bend(10K)(@24 between centers) recently for $500 off of craigslist,couldn't be happier.(It's almost exactly what I was looking for)

However,as with anything used,it has some wear.

I knew going in it was going to be a Project(I'm going to do a mechanical restoration as well as a "make it pretty" resto.) but as it sits It'll keep .01 or so tolerance over 12" which is as good as I'll need.
since then, I've gotten a QC toolpost (chinese made,@$200) 6" 3 jaw chuck(christmas gift,@150)6" 4 jaw chuck(again,christmas@ $150)and a chinese made jacobs chuck and live center(@ $60 for both)
I'll probably spend another 2-300 getting it where I want it to be(paint,felt,oil,cleaning and rust removal)but I don't really have a time frame to be done,so that's going for me.
It depends on what you are looking for,the deals are out there to be had,but if you need something"right now" it will cost you more than if you can find a deal and whether you want to spend time fixing something or just buy and start making chips.
YMMV.

[Rafiki]

Originally Posted by LuciferMutt

You may well be better off with taps and dies and the tooling to hold them/align them to the tailstock.

Anything up to 1/2"-13mm,taps are the way to go.taps/dies are cheap up to that point I think.

[smilin'Ed]

chuck key left in the chuck and getting thrown out is a common story. Make a cover over the on switch that only the small end of the key will fit through. Then you need the key to turn it on and can't leave it in the chuck.

E

[sailah]

I'm a rank amateur with a lathe but I've owned one for 2 years now. I'm glad I did not get a smaller one. I have a 13 x 40 Enco, Quick change, metric threading. It came with a face plate (never used it), 4 jaw (used maybe once), 6" 3 jaw (use every day), nice ball bearing center (a must).

Just learning on a lathe, here's what I would want/need the lathe to come with

Lathe
3 jaw chuck & key
Tailstock
Center
Cutoff tool holder
Tool holder
HSS tool blanks


Things that it doesn't need to have but you are really going to want almost immediately.

drill chuck with taper for your tailstock
measuring tools like calipers mics
taper shank drill bits but you can probably get by with a nice drill index and chuck
aloris type tool post holder (look for an enco sale on PhaseII and find a 20% coupon)

As far as finding a lathe, if you are searching where everyone else is searching, you're going to come up with crap deals. Or you need to be Johnny on the spot with cash.

Don't waste money on a crap mini lathe, sorry but they are an exercise in frustration. Don't think of it as spending money, it's an investment in a quality tool. That's what I tell me wife at least

Go to school auctions, auctionzip.com, irsauctions etc and find a deal on a good machine. Don't be put off by three phase, and here's why. You want three phase because all the heavy industrial machines are three phase and there are reasons for it. We won't get into those, but we'll instead talk about how you are going to make that work for you.

No one else in your shoes wants three phase tools either because they don't have three phase in my garage. neither do I, until I make it myself Accomplished two ways. A VFD or a rotary phase converter. You want a VFD for a lathe. They cost $130, and I can easily explain how to wire it. Takes 110v or 220v coming in, and outputs 3 phase 220. You get access to a whole range of machines that other hobbyists are turning away and you get instant variable speed, soft start, braking etc. You can even wire in a simple rheostat from radio shack for $10 that will allow you to change speed with the turn of a dial. Sweet.

So anyways, you have a budget which is reasonable of $1000 lets say. I have been to numerous industrial auctions where a 14" Clausing with an Aloris toolpost sold for $400 and the auctioneer had to beg for that. The toolpost is worth more than that. And it came with chucks etc. Unless you are lucky with clist, everyone else will get those deals faster. Start going to live auctions where commercial businesses are liquidating and you will find deals that will make you slap your forehead I promise.

http://www.factorymation.com/Product...M50-101-C.html

here's an auction 10 miles from my house next week. These are the ones to go to to get machines and especially tooling which is very expensive buying one at a time. Based on auctions past, I doubt that lathe will get more than $1500...

http://www.auctionzip.com/cgi-bin/au...232&category=8

[Yellow Iron]

I got this small Altlas given to me
It needs some work and Im trying to figure out how to make it run in the correct direction

[Rafiki]

Originally Posted by sailah

Don't waste money on a crap mini lathe, sorry but they are an exercise in frustration. Don't think of it as spending money, it's an investment in a quality tool. That's what I tell me wife at least

BTW the 10 k I referenced earlier was built in 1960.

[P B G]

Yellow island you just turn that red knob the other direction!

Good practice with the chuck is that whenever you use the chuck key, you need to make sure you turn the spindle by hand to make sure that the jaws of the chuck don't smack the bed, or the carriage. Just a quick turn ensures no interference, and no chuck key issues.


In the MC world the centers let you turn things like fork tubes slowly and use dial indicators to read deflection.

[sailah]

Originally Posted by Rafiki

BTW the 10 k I referenced earlier was built in 1960.

I was referring to the harbor freight 7 x 10 clones

[pvangel]

You could get a used Smithy for your budget# and it will come with tooling and the benefit of a mill as well. Should be fine for your intended use.

[LuciferMutt]

REgarding a VFD to power a three phase machine:

I did this in my shop to an old 12" Clausing and tore out the old hydraulic vari-speed cone pulley assembly and fabricated my own motor mount and just a 1:1 belt drive from the motor to the headstock pulley. New inverter duty motor.

It works fine except that the motor does not supply very much torque at lower RPM and I have stalled the machine attempting to drill large (1-2" diameter drill) holes through plastic stock at 600 RPM and down. Back gear has a maxium speed of something like 256 RPM as measured with a tach, so there is a range from about 300-6/700 RPM in open belt where the motor does not make much useful torque. Other than that, it performs very nicely and is VERY quiet! Could never say that about that stupid vari-speed.

So, in short, VFDs are a great way to get three phase in your garage if set up properly, but low MOTOR rpm does not produce much torque.

[sailah]

Yeah mine is 3hp so I don't have that problem but it can be solved with a sensor less vector drive for a little more money

[Keith]

I recently bought a 6" Atlas MK2 lathe. It's a pretty handly little unit, but I can already see the need for something bigger.

[Ricardito]

what an education I'm getting for free! (I ought to know a good deal in this regard since I'm a prof at CU Boulder). Thus far, I'd jump at the chance of buying, among a few others, either the "Myford 7" given to Chobro by his dad or the blue "Smithy" suggested by pvangel in his post. Also please know that I am very very mindful of how dangerous these machines are. I plan to hang a large red lettered sign on the wall above the lathe so that I never forget to operate it with ample caution and never in a hurry.
Again, I'm grateful for all of the great advice offered here. And, also again, if anyone knows of one or has one for sale, please PM or email me landeira@colorado.edu