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View Full Version : Suggestions on a lathe


saands
March 12, 2011, 04:18 PM
Hi everyone,

I have had evening/weekend access to nice CNC lathes/mills at work for many years, but as "my" tools are becoming increasingly utilized for real work, I am finding myself in the market for a lathe of my own. I realize that I will not have (essentially) unlimited size and horsepower (160 inches between centers and 50HP won't fit in my garage or my budget) and that is fine. I am also pretty sure that I would rather spend the CNC money on the mill than on the lathe, so a manual lathe is also what I am expecting.

This is a hobby tool, not a livelihood tool. I was wondering if there are some general thoughts people could share on brands that I should seek-out or avoid-like-the-plague.

I would also like to solicit some input on what I am considering as a minimum configuration.

Swing over bed > 6"
Swing over cross-slide > 4"
Distance between centers > 20"
Steady rest required, follower rest a plus
Spindle bore > 1.25"
Tailstock travel > 1"
there is a list of standard stuff like threading, etc.

Thanks in advance for your thoughts.

By the way, I can't spend more than $5k on the lathe ... a LOT less would, of course, be preferable.

Saands

Clark
March 13, 2011, 02:28 AM
The most important thing about lathes is getting past the wife.

They maybe ok with the cost and the cost of tooling, but the size is a shocker. My wife did not want to look at my lathe.
She arranged to have a slab poured and I built the shop.
She made schematics and re wired the circuit breaker panel in the house, and I installed the boxes and pulled the wires.
I got some help lifting the sheet rock to the ceiling.
Once I was hidden, I got a mill.

Think about it.

I am on my 4th gunsmithing lathe, but I am still on my first wife.

Rifleman1776
March 13, 2011, 07:51 AM
A friend who has been an engineer and gunsmith his entire life bought a Grizzly and calls it the "Cadillac" of all the lathes he has ever worked with. Check their catalog for specs. and pick the one that best suits your needs. I think they have (or had) specially designed for gunsmithing.

psyfly
March 13, 2011, 07:55 AM
They're really nice to have.

I have an old South Bend that I havent't used regularly for several years.

It has a 42" bed and I haven't measured swing or distance between centers (I bought it used) it was for many years a handy thing to have on the homestead. I lived 40 miles from town and it was often easier and faster to make a part or tool than to go to town to get it.

I'd love to sell or trade it away, but it's difficult to ship and I have no idea what it's worth anyway.

I am in no way a gunsmith and did not use it for that purpose, although I have made a simple part or two over the years. That being said, I bought it from a gunsmith's estate in 1984 and will still occasionally make myself something I need.

They are an invaluable toy for the hobbyist of most any kind (well, maybe not stamp-collecting :D).

I don't think you could go wrong finding an old South Bend or Atlas.

Best,

Will

HiBC
March 13, 2011, 04:12 PM
Generally at a 10 in swing is when you get the 1 3/8 or so hole through the spindle.That is desireable.You can use a 5c collet setup with the simple hand wheel drawbar.
You can also put most barrels through the headstock that way.
The toolpost I bought was a Yuasa clone of the Aloris dovetail post. there are other Aloris clones.Enco sells a superb Swiss quick change tool post,but its pricey.
A micrometer carriage stop is a nice feature.
Maybe they work out,but the gap bed feature on a lot of the import lathes is unattractive to me.

saands
March 13, 2011, 07:37 PM
Thanks for the inputs ... and advice. Fortunately, the wife is totally on board with this acquisition. Although I will keep the spousal caution in mind when it comes to setting expectations for the size :D

Saands

Scorch
March 13, 2011, 10:01 PM
A gi=uy I know just bought one of these:
http://www.grizzly.com/products/category.aspx?key=561

saands
March 13, 2011, 10:56 PM
Yikes :eek: That is a little rich for this project's budget ... a tad more and I could get a new US made CNC Haas ... OK ... not really a tad, just double ;) ...

Saands

Clark
March 14, 2011, 03:52 AM
My 4th gunsmithing lathe, a PM1236 was $3k delivered, a little more with DRO

http://www.machinetoolonline.com/PM1236.html

saands
March 14, 2011, 10:00 AM
Clark: Do you like this PM 1236? It looks a lot like the Grizzly 4003G, but with the DRO is a handier setup and it looks like it comes with more goodies (like the tool post and holders). Just for clarity, do you have 4 lathes in your shop or is this the fourth lathe to occupy the lathe position in your shop? I only ask because if it is the latter, then I'd be interested in knowing what your progression was and why ... I know that if I replaced 3 lathes, there'd be a darn good reason behind each move.

Thanks,

Saands

kraigwy
March 14, 2011, 10:53 AM
Mine is an older (early 1980s) Jet 1236. I would think for gun work (assuming that's what you want to do since this is a gun forum) you would want at least 36 centers and 1 1/2 spendle hole.

I got a Jet 16 Milling machine about the same time, beteen the two there isn't a whole lot I can't do as to guns.

Never had a CNC, whouldn't know how to work the puppy if I did. I have made some pretty accurate rifles on the equipment I have.

saands
March 14, 2011, 11:29 AM
Nice to hear that the imports (at least one) can have 3 decades of service in them ... build quality is one of my biggest concerns with getting a new lathe in this price range. I feel blessed that $3k isn't the difference between eating and starving for us this year, but it is still WAAAY too much to just throw away on something that will only last 2 years.

As for CNC, there are a few things that get simpler with them (like milling a hole to a diameter that you don't have a drill for) ... but mostly they are just nice when you want to make 2 or more of something ...

Thanks all,

Saands

tango1niner
March 14, 2011, 12:16 PM
I have a 10" swing Sheldon lathe, total length of bed 56", length between ctrs. is over 30", spindle bore is 1 3/8". I like this brand over the South Bend (another good lathe) as the bed casting is heavier (rigidity is what its all about). A friend has a chinese lathe which looked very nice and modern, the only problem was a cumulative leed error when threading. It cut threads great for very short lengths of engagement. The problem was for the longer lengths. Another reason I like Sheldon is because it is old AMERICAN IRON !

Clark
March 14, 2011, 03:59 PM
The Jet, Grizzly, Precision Matthews, and virtually any lathe for gunsmithing that is with in the price range of gunsmithing is going to be made with mostly interchangeable parts from China.

Chinese national businessmen* are almost impossible to deal with for green horn Americans.

Jet, Grizzly, Precision Matthews, Harbor Freight, ect all do a great job of fighting with the Chinese to get the product, and then supporting the customer.

I think the Precision Matthews has a great foot break and upgraded contactors [relays] as a pro compared to the others.

I think that the Precision Mathews quick change gears with dial driven rack an pinion selector is inferior to the old U shaped selectors.

This thread got me to buy a Precision Matthews PM1236, and on page 19 of the thread you can see me fixing mine when I screwed it up after a year:
link to candlepower thread (http://www.candlepowerforums.com/vb/showthread.php?216408-my-new-lathe-...-Precision-Matthews-12x36-...)

Kombayotch, one of the smartest gun posters on the internet has since purchased a PM1236, so don't question MY wisdom about the purchase.

Lathes are like guitars, and Eric Clapton will sound better than me with any brand guitar. Likewise my brother and his Jet seem to produce jewelry like gunsmithing, while mine looks like the work of Homer Simpson.

What does it all mean?
It won't matter that much what brand of lathe you get. 12x36 is big enough for gunsmithing.



*Chinese American businessmen are extremely honest, and completely different culture.

HiBC
March 14, 2011, 08:46 PM
I do not know the PM lathe.I do see some feature I like.The fellow with the Sheldon,Its a tossup,really.I have earned my living running some very fine old lathes.I have also spent a fair amount of time ripping off .250 cuts on 4 in stock,17-4 PH with about an .012 feed.The 15 in Colchester,of course the Monarchs,and the Cincinnati Hydra Shift could do that.The old 10 in EE Monarch toolroom lathes are a dream.
I spent a lot of time running little 10 inch Harrisons I like that lathe.The little variable sheave 10 in Clausings are great for light work,till the drive wears out,then they make horrible noise.
These industrial machines are tough,but,the have had a history of 64 operators,some of them morons.A lot of folks never put a drop of oil in a cup or on the ways,blow the machines with 90 lb shop air,do heavy knurling,spin drills and tapers on the tailstock,do not clean the chips off a spindle nose when changing chucks ....etc.And something is wrong if these machines sit idle more than a few hours a day.They run,day in day out.They wear.25,40,60 year old machines are hard the get parts for.
Even if these import machines would be junk in a few years in a machine shop,A gunsmith may only run one a few hours a week.He does not need to run a 2 in drill 14 in deep in pre hard 4140.He carefully feeds in a chamber reamer,or cuts 12 TPI.
So,it mat be a new,straight set of ways,and a tailstock with clean perfect tapers,half nuts that have not been run partially engaged,etc.If just 1 guy runs it like he cares,for 10 hours a month gun work is light duty.,a new Grizzly or Jet or PM may be the way to go

The lathe I do hobby grade gunsmithing on iss a 1942 Navy Signal Corps 10 by 36 South Bend.Its been gone through,a new 3 jaw,4 jaw,Burnerd multi-collets,Yuasa toolpost,taper attachment.We just hold our lips right,and it does fine.
My brother called today and said a co worker just bought a restored Cincinnati Hydrashift for $3600.More guts than you need for gunsmithing,and maybe .0027 or so is the finest feed,but a fine machine.

Unclenick
March 14, 2011, 09:35 PM
Agree that gunsmithing lathes have a pretty easy life. Mine is a Chinese 13x40 I got on sale with DRO from Enco a number of years ago. It's funky in several ways, but mostly does what I need. It has a D4 Spindle, which I find convenient because I switch between the 3 and 4 jaw chucks and the faceplate not too infrequently when I'm working on larger projects (not gunsmithing) with it. The lead screws is inch, rather than metric, so the metric threads are the ones that go off after bit of length because the change gears don't have a 127 tooth gear (essential to exact conversions from inch to metric). The cross slide and compound toolpost and the tailstock have screws that are 1/8" pitch rather than 1/10" inch, which I would find annoying without the DRO.

If I were buying over again, I might either have spent a bit more on a machine with helical gears in the head or less on a belt drive machine to cut down vibration. The linked polyurethane belts do quite will at isolating vibration, though I don't recall being aware of them at the time I got the machine. Vibration tends to make survival of carbide or other ceramic inserts short, as it encourages the edges to chip. I wound up having to build a fairly heavy base for it and to take some other steps to calm it down. I did get a nice Dorian quick change tool post that is a big convenience.

Bogie
March 15, 2011, 01:52 PM
The smaller Grizzly "Gunsmith's" lathe looks interesting for the money... I'm considering one of those. Main thing is just tightening stuff up to eliminate runout.... Maybe truing the jaws on the chucks, etc...

One thing I -really- want when I get the first "this is mine" lathe is a drawbar collet system - if you're doing any sort of production on smaller parts, that's the way to go.

One thing to consider too is "Do I want to mess with three phase, or can I struggle along with regular 220, or do I just wanna plug it into the wall?"

Day to day, I've been using a Hardinge 2nd operation lathe, a big ol Japanese thing that I'm not sure who made it, a Jet and a Bridgeport mill, and I've gotten pretty good at changing parts and hitting da button on a Shizuoka AN-S CNC mill. We're getting ready to get another Shizuoka up and running, and our Milltronics Partner X is down for maintenance right now.

HiBC
March 15, 2011, 07:02 PM
Our old Southbend has a simple handwheel/drawbar 5-c setup.A few years back we found a fellow who sells and services these.I suggest buying 5-c collets with internal threads in the shanks.These accept the thread in collet stops.And,if you have 5-c collets,a set of collet blocks with a quick change lever is cheap and useful.Even a POS Spindex 5 C fixture will do many things if you hold your lips right.
If the lathe has a 3 phase motor,you will need a phase converter to power it.
The Phase -a-matics are inexpensive and they work OK.You get a better 3-phase from a rotary converter.
Yuasa,Buck,and some others make a 3 jaw that has centering srews in the side.You can adjust the runnout away ,just like with a 4 jaw.
Get a reversable jaw chuck.You can replace the jaws with soft jaws and bore them to fit a workpiece.