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lane
10-15-2008, 08:11 PM
Ok here goes . Joe Blow wants a lathe , And ask on this forum what to get.
He is looking at a new Chinese lathe and a old used piece of American iron.

First question to ask is . What does Joe B know about a lathe . Is he a newbie are a old hand at running one.
Does he know the difference between a old wore out piece of American iron and a new piece of Chinese junk.Just because it is new that does not mean it is any good.
Does he have the ability .the know how and the tools to rebuild and old wore out machine. Also can he fix and improve the new Chinese machine.
If he is new and knows nothing about a lathe . I would say buy NEW but shop around and ASK lots of Questions .

Beg borrow are steal some one to help you that knows machinery and can go with you to look at some. All new machines are not the same.

Look at the speed range at least 30 - 1800 RPM .Plenty of lathes have the high end but it is the low end the counts.
What comes with the lathe as far as tooling. Must have`s are 3 and 4 jaw chucks and what comes with most new lathes are not much good ,they just get you started. Needs steady rest follower is nice. Need live center and 1/2 inch drill chuck and good tool post Quick change if at all possible
That being the very basic stuff.
Look at the fit and finish of the machine .How are the handles and the controls laid out . Do the work properly and do they look real are do they look cheap ,If cheap on the out side where you can see what do you think is inside where you can`t see.
Are the handles chrome plated ,plating wheres off and chips. Bare steel handles are better. Plastic knobs brake and fall off.
What size taper in tail stock.
How does the chuck mount their are 4 different systems
Thread spindle nose like South Bend.
L series like some Clausing`s.
D series most Chinese lathes
A series which is a bolt on.
Does the lathe sit on a cabinet are is the bed bolted to a cast iron base.
What size lathe . What does it swing and how much between centers.
Last but not least what are you going to build . Small stuff ,large parts are just what ever. you will be limited buy the size.
Now can you get parts for this thing 10 years down the road if you tare something up . Are can you make your own parts for it.
The gears in metric lathes are module and usually harden The gears in old American are easier to make if have to.
Is this a belt drive machine are gear head . A belt drive is far more for giving for a newbie, a gear head will tare stuff up in a hurry.
Now that Joe Blow has a new lathe Does he know how to set it up and level it and turn a test piece and make the finial set up to cut straight and all necessary adjustments because it is Not ready to run out of the box.

May be this will help some one and feel free to add any thing I might have forgotten.

Fasttrack
10-15-2008, 08:59 PM
Excellent. While the rest of us argue, you have compiled a great list for a prospective lathe owner.

For the newbies out there, I would (and do!) give serious credit to what Lane has to say. I think most of the members on the board would agree that he is an excellent machinist and takes a realistic attitude towards machine work. You have to watch out for guys like me - I can blow smoke for hours ;)

wierdscience
10-15-2008, 09:43 PM
Good job Lane,that about nails it.

Can this be posted as a sticky?

J Tiers
10-15-2008, 10:09 PM
I'd add that

as far as spindle types, the threaded is the cheapest to get or make chuck mounts etc for, but has the disadvantage of potentially unwinding in reverse. That can be a hassle for some tricky threading jobs.
The other mount types won't un-thread (obviously) but may be much more expensive to get chuck mounts etc for, and it is rather difficult to make them yourself.

A first step BEFORE buying ANY machine is to at least "Book-Learn" how to run that sort of machine. The Audels High School shop manuals in the US are good for that. Learn how a job is put on it, how the controls work, what the usual and customary features do, how attachments are put on and used with it.
Armed with that much knowledge, you will be in a far better position to understand whether for a used machine the parts are there, the controls work, etc. For a new machine, you will have a much better idea how the different trade-offs of feature may affect you.
Relying on a machinist friend puts you at the mercy of his (or her) biases and so forth.... And they may be very conservative, knowing you will be grumpy with them if they overlook something. It's YOUR purchase, and YOUR responsibility to make the final decision, learn enough to do that in a somewhat informed fashion up front.

If there is ANY way you can get even a LITTLE time actually using the same type of machine (lathe, mill, etc) before you buy one, do that. If you can, do several of the basic tasks, turning, threading, facing, on a lathe for instance. It is amazing the help even slight experience can be.

Realize going in that new or used, you will NOT get a perfect fit, most likely..... New machines all have feature tradeoffs (they are essentially all chinese now, and made to a price, not for a job). Used machines have wear, possible or actual problems, and feature limits just like new ones. it is your job to make the best choice based on everything you can learn.

I have done the above, and only got really "burned" ONCE. That was a die filer, which had a known problem which I thought I could fix. And I COULD, but it turned out to be too much hassle. I sold that machine for what i had in it, fully disclosing the problem. The "burned" means that I was never able to use the machine for its purpose effectively. I also once bought a "AA" lathe, which is truly a POS, but I DID use that for quite a while, improved it, and sold it for more than I had in it.

macona
10-16-2008, 01:35 AM
Good chrome dont flake. Mine is 66 yrs old and its still fine.

Just Bob Again
10-16-2008, 07:21 AM
What does "worn out" mean? You don't want pieces broken, but "worn out" is overused and often irrelevant. Take an old lathe where the ways are worn with a 20 thousandths hollow. Easily visible with a ruler. Junk, right? No, do the math and that only makes an error in diameter of 4 tenths. Generally fine for a home shop. If the ways are not straight, that's a bigger problem and harder to see. Gears are worn. Backlash often gets taken up when you cut. Quill is loose. For drilling, the drill self-centers. Lots of free motion in the screws. Likewise, often unimportant. Judging a used machine is an art. Often the things that look bad have little effect on the final product. For production, where things must be consistent, it may be a big problem. For toolroom or home shop where you measure and cut, might make no difference at all. Until you have some experience, judging either a new or used machine is near impossible. You might go with cosmetic appearance and that isn't a good indication of how well it cuts.

No quick-change gearbox? So long as it has the change gears, that's a 3-minute job. Taper attachment? Offset the tailstock for shallow tapers. A bigger problem if you intend to cut long tapers with greater angles.

Collets? Nice. More accurate and more consistent than a chuck. If your machine has none, morse-taper collets can be found fairly cheap. They are not through collets. Can't hold a long piece. 3C only goes up to half inch. 5C to an inch or more, depending. Old machine with odd B&S collets? You may spend more than the cost of the machine to get a set.

Sometimes major features make no difference. Sometimes minor ones are the deciding factor, depending on the work you do.

So, you got a great deal on a machine. Ready to make chips. The chucks are sprung and you got a lantern toolpost with one bit. What do you need to make it work? Drills, bits, center drills, centers (live and dead), dogs, faceplate, QC toolpost, indicators and holders, micrometers, calipers, new chuck, knurls, boring bars, tailstock chuck, collets, drawbar, etc. This is tooling. Nice machine and no tooling = no chips. $ hundreds to $thousands for tooling. The good thing is that most of it is useful for your next lathe. You're going to pick the right one on the first try? Given the wide range of features and quality, not likely.

Import versus domestic? Too many reverse-snobs lurking here to comment. If you read this, you NEED a lathe. Probably a couple. Buy one. An old piece of junk or a new piece of junk is better than no piece of junk.

J Tiers
10-16-2008, 08:09 AM
What does "worn out" mean? You don't want pieces broken, but "worn out" is overused and often irrelevant. Take an old lathe where the ways are worn with a 20 thousandths hollow. Easily visible with a ruler. Junk, right? No, do the math and that only makes an error in diameter of 4 tenths. Generally fine for a home shop.

Not so fast...........

The error depends a LOT on the size of the part being turned.

What is insignificant on a part 3" diameter, may be a lot more significant on a part 0.187 diameter, or smaller.

The good news is that smaller parts "usually" are short, and the worn ways may not be a problem for short pieces.

torker
10-16-2008, 08:31 AM
Old US iron huh? I own some old iron. Got my old Ohio mill. Very cool machine to look at... very cool to run.
BUT...it is about as clapped out as a machine can get. The spindle is bent...how the hell they bent something that big is beyond me but it wobbles .050.
The ways are worn really badly. There is at least two turns of backlash on X.
I can't do any serious work on this ol' girl but it serves a real purpose in my fab shop.. I use it for heavy roughing for plates etc. It'll take a 3/16" doc with a 6" cutter.
The old McDougal heavy lathe I was partners with (long story)... we took a machinist with us to look at it. He even got fooled. Many of you know that the spindle saddles are torn up really badly. The lathe is unusable and requires a ton of work yet.
Quick and easy but gets the job done...my Chinaman and Taiwanese machines are the real money makers in my shop.
They will do until I get better stuff.(Oh just wait til I get the big VN fired up)(Then I promise.. I will be a snob :D)
Russ

oldtiffie
10-16-2008, 08:47 AM
I don't know why so may are so "hung up" on turning to tenths.

If you or your lathe can do it with a good finish - fine.

There is nothing wrong with finishing off by using a good technique and a good machine file and perhaps some emery paper and some scouring pads from the kitchen.

Even on a mill, its not improper to take the part off the mill and finish or "ease" it with a file or a scraper.

It would not be the first time I've been able to just take a "whisker" off a flat surface by putting it on the side of the grinding wheel on a pedestal grinder. It might surprise you just how well it can work with a bit of practice. Try it an see.

Horses for courses.

What ever it takes.

Davek0974
10-16-2008, 09:02 AM
Hmmm,

its a good list but i posted exactly the same if not more yesterday in another ongoing thread?


Dave

Kudu
10-16-2008, 05:22 PM
I own 3 lathes. 2m Tos, Colchester Mascot and a Voest Apollo. All 3 machines are over 20 years old and in perfect condition. I turn precision shafts and crank shafts for Eccentric presses. Heavy threads, Heavy parting. Bearing sizes. Parts for Harley Davidson etc etc. The trick is to scout around and be patient until you pick up a very good machine. I paid less than half the price of a new Chinese machine and am extremely satisfied.
My friand has a 3 year old Chinese machine and it's condition is not even worth commenting on. If you are going to earn a living with a lathe then I would go for European. (personal opinion)
Buy the way I have just purchased a Large Droop & Rein Mill. Also perfect. For R100 000 South African Rand. Going to use it as a boring mill. It is more versitile and handle the bigger cuts.

lane
10-16-2008, 06:49 PM
After reading some of the answers . Yes I will agree.
If you have a lathe and know how to use it and what it will do ok.
But for the newbie who knows nothing except I want to build this and I need a lathe You can buy good used machinery .But will say again Know what you are looking at . Parts may not be broken ,But if you do not understand what wear will do to you look out. Yes I can take a piece of wore out Junk and make good parts on it but can you.
Like an old shop foreman explained to me many many years ago .(Any one can run a new lathe it takes a real machinist to run junk.)then said when you can make good parts on these old wore out machines I will get you a new one. I did and so did he.
And again we are not turning to tenths = - .001 is close enough for most things and a lot of people have a hard time doing that. Besides learn to use a file and sand paper .If you are careful you can get things just like you want with out much trouble.
Just because a machine is old does not mean it is wore out . I run a 40 year old Clausing Colchester at work which I would love to own. Yes the paint is scratched and the cast iron is brown with rust but the lathe works like a new one.
Also I am not talking about old American chrome on the handles but the cheap Chinese stuff. Chrome over pot metal.
And just remember like any thing else machinery will ware out in time I have wore out at least 3 Bridgeports over the past 40 years. When the wear out for one job you use them for something of lesser quality.
But back to the newbie its all in what you know and if you can do what you want with what you got are can get. You old guy`s that are making a living doing this like me don`t even have to read this.
Just remember one man`s junk is another mans treasure. And yes we also have a big Jet lathe 3 1/2 hole in spindle !4 x40 about 10 years old and very little use ,but to me it is junk does every thing like it should but the 40 year old Clausing puts it to shame. \
After you have time on 50+ different machines then you can compare them. and you will know what is what.

Bill Pace
10-16-2008, 10:04 PM
Some comments from the "been there, done that" side of this discussion..... while I'm not exactly a "noobie" still, I,m a long way from Lanes and other of you guys abilities/experience -- perhaps an "advanced" noobie:rolleyes:.

Some 4 yrs ago -- long before I found this forum, and met Lane, I was desperately trying to get away from my first lathe venture, a badly clapped out 9A South Bend and into something that I could actually enjoy using! Had my heart set on a nice condition South bend 10, but down here in machinery wasteland, it wasnt happening, so after some 3-4 months of frustration, I started to gather info on the Chinese machines. I bout wore a keyboard out Googling and reading, finally settling on a 12x36 Birmingham. In many ways I was fortunate in that, despite my lack of experience, I got a lathe that I REALLY enjoy -- I could have just as easily gotten one of the nightmares out there. Old American iron is very desirable, but more and more the facts are that they just arent out there for a large portion of the new comers --- and ---, just might not be in the best interest for a noobie.

Lane had an excellent idea to start this thread and add his thoughts about some of the many things to consider in the purchase of that mill or lathe that is SO critical in the setting up -- AND, enjoying of your shop. And along with his initial thoughts and recommendations have already followed several other posters with additional views on this.

This could easily become one of the more informative posts we'll see , and thought should be given to keeping it at the forefront as a sticky ---or something -- if nothing else maybe some one will give it a bump once in a while.

rantbot
10-17-2008, 01:07 AM
Had my heart set on a nice condition South bend 10, but down here in machinery wasteland, it wasnt happening, so after some 3-4 months of frustration, I started to gather info on the Chinese machines ... Old American iron is very desirable, but more and more the facts are that they just arent out there for a large portion of the new comers
Which is why I never wasted any effort hunting around for a South Bend - I knew perfectly well that every last man, woman and child in the state seemed to be doing the same, and the price would be grossly overinflated even when I found one.

Fortunately, there's a lot more to the 10" Old Iron market than just South Bend. Spread the sights a bit wider, and more targets appear.

lane
10-17-2008, 08:55 PM
Just a few more thoughts on the subject.
All of you have it pretty good. In 1974 when I got my first lathe. I had been through Trade School and had about 7 years in the trade in 3 different shops by then. I had never seen a lathe smaller than a 16 inch swing machine.The first shop had a 16 inch South Bend we called the little lathe every thing else was 18 inch and up to 54. I ran a extra heavy duty 18 inch Monarch the bed was 3 1/2 feet wide and the v ways were over 3 inches wide at the base.
Any way in 74 I was in a place to buy precision tools every Friday I would get of work early enough to drive down their and spend some money on tools . they sold Brown &Sharp ,SPI , and Mitutoyo brands. Well I walked in and setting in the lobby was the cutest little lathe you ever saw. with every tool that was made for it . It was a Atlas 10 inch. Never in my life had i seen are even knew they made lathes that small. I asked the tool guy about the lathe and he said it belonged to one of the owners and was for sell and took me to talk with the guy about the lathe and I end up buying it in a few weeks. for $995.00and it all started with that.
After a few years I did find out their were more small lathes built and small other machines but had only seen very few. The big thing was at that time No foreign machinery so if you got any thing it was old american.
all we even had in Trade school was 15 an16 inch are bigger left over world war II stuff. Even a few WW I machines when I first started. In 1978 I went to work for a 2 man shop and the boss had a 9 inch South Bend that I fell in love with , tried to find one but around her no luck so I sold the Atlas and ordered a South bend 10K But had to wait a year before it came in , Man that was a long wait.
So now days you have lots of choices Big Small used, new lots of foreign makes and lots of styles just take your pick.
And it is the same way with mills back then you had Bridgeport and Bridgeport for small Rockwell and Clausing if you could find one and that was it . Yes I know their were some other European stuff but not around here. Kind of like living in a one car dealer ship town who sold Ford`s like it are not you bought Ford