Your advice on an used metal lathe

Grizzly Adams said:
I've found, sometimes an operation requires more thought than work. :)

Grizz
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I'm with Trev on this. Oh sure, there's a lot of simple things that get done where very little thought is needed. But the ones that require significant head scratching and planning greatly add up to way more overall time in the shop thinking than actually twiddling the wheels.

More than a few times I've had to spend a couple of hours to make some special bit or tool or jig so I could make a part which in the end takes just 10 minutes. But without the jig, tool, accessory or special hold down clamp it would not have been possible to make the final piece in the first place.

Case in point. I recently got a couple of Winchester 1897 takedown shotguns to use for the Wild Bunch event in cowboy action. I got both of them from different folks for pretty cheap. But both were loose in the barrel to receiver and there was not enough teeth in the adjustment range. This meant that I needed a different number threaded collar with a different thread offset from inner to outer.... well, no one in the area had one of these kits. But I've got a machine shop. So I made myself a couple of universal fully toothed collars.

But wait, it gets better. Turns out the ID threading is a highly unusual 30 teeth per inch. As it happens my lathe came with some extra gears that allowed me to generate a 0.8x (or 1.25x if used the other way) shift in the gear train to the threading gearbox. So that allowed me to set up these gears for the 1.25x setting and run the gear box at the 24tpi setting to get my 30tpi pitch. After that I switched it back to normal and cut the 20tpi OD thread pitch (I think it was 20, been quite a few months now).

Then from there I used the simple but handy as heck spindexer on my mill with a regular end mill set to cut into the collar at the 45° position to generate a 90° V tooth on the collar and by indexing 8° at a time to produce the 40 teeth around the collar I needed to allow for full circumference use with the little collar locking peg that engages a few of these teeth.

So yeah, a lot of setup changes and care to machine what in the final "item in the hand" view seems like a pretty simple part.
In some cases those special bits of stuff come in handy on a regular basis. But often as not the tool, spud or whatever is a "one shot wonder" and never is needed again.
 
My SouthBend needed a feed nut for the cross feed. It was 2.5 x 12mm left hand acme thread.
Not something you can get at the local industrial supply. I ground a tool bit using the unworn part of the shaft for a pattern.
Made a tap out of a piece of 1/2" W1 drill rod hardened and tempered it. Made a new nut out of brass that I had lying around.
Cut threads in it with my home made tap. It took a lot of force. I should have made the tap longer with more taper.
You can see the twist it developed cutting the brass. In the end it worked out perfectly.
Terry

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Nice to see that this thread is still going!

I have no machinist experience but bought myself a used mini lathe recently. Came with a manual and a bunch of books so hopefully this winter I'll have some time to start playing with it.

Here it is;
 
Like a previous poster said. A lot of thought can go into making something!
I ran the lathe in reverse with the tool bit upside down in the tool holder to cut the left hand thread.
I ground the tool bit and fit it into the cross feed screw holding it up to a light until I had a good fit.
It took quite a few tries to get it right.

Terry
 
Bertn, my own lathe is a 12x36. But when I think about it 95% or more of the gunsmithing things I've done on my lathe were smaller items which I could have done on your mini lathe. So don't feel like you can't join in the fun and make some of your own replacement parts. You won't be doing any barrel work any time soon on that size of machine but you'd be surprised at all the other things you can do if you like tinkering with some older guns that need a good dose of TLC to get running again. Or bits and pieces to deal with reloading older vintage style ammo.

I've already made around a dozen different collars, adapters, custom neck sizing and flaring loading die inserts and such for reloading and will be making more as I go along. Most of them were related to my love for .38-55 caliber guns. But I've done a few things to connect powder measures to flaring tools and the like too. Even made a funky little connector for my Dillon powder measure to make it easier to hook the rod to the measure up to the lower arm. All of these things could be done on a mini lathe just fine.
 
Ditto. My go-to lathe is my Myford Super 7, 7 inches swing, by about 18 inches between centers. Won't chamber a rifle barrel on it, but 90+ percent of the stuff that comes up, I can do with it, and it's always there ready for when I need to do a small job.

I REALLY need a decent sized shop! I have a Colchester Master 2500 that I would like to actually get some use out of. That is a 13x40 size lathe with a 2500 rpm top speed. Need to wire in one of my VFD's and a 220v 3Ph motor that I have for it.
Between those two, I also have an Emco Super 11, which has the same size spindle and mounts as the Colchester, D1-4 Camlock, and a large enough spindle bore to fit a barrel blank in to.

I first started looking for a lathe back in the early 1980's, been gathering, upgrading, and accumulating ever since.
 
Nothing shabby about that Emco. If you know about Stefan Gotteswinter on YouTube that it's a Super 11 he's using. And he does some nice and sizeable work on that.

Mind you, when you get that Colchester working it'll make you grin like the Cheshire cat when you hog off a big 1/4" wide strip of mild steel and the machine barely gives a little grunt when the motor digs in and the machine just coasts through the metal like a kid's tongue through soft ice cream.... :D
 
Bertn, looking at your picture again. When you get around to using it try to keep the cutter closer to being over the carriage's footprint on the bed. As shown in the picture the tool is sitting well forward of that direct like of support. When cutting that's going to generate a lot of torque that tries to lift up the tail end of the carriage and bring it away from firm contact with the actual bed. And that's not a good thing on a small lathe. It'll make the machine prone to chatter simply because it does not have a lot of mass to hold the carriage down.

Ideally you would swap out the tool post with one that is more compact and positions the cutting tip closer to the center bolt and keeps the actual cutting tip positioned more centerly over the footprint of the carriage where it sits on the bedways. And if not close to center at least within the footprint of the carriage. That way the forces all extend down directly and force the carraige more firmly to the bed instead of racking it up and trying to tip it.

Along with that always choke the tools in close to the holder. And keep the holders compact as practical. It's all about reducing the "overhang". You always want as short and most direct a path to a direct vertical load. Doing so is even more important on a small and light machine tool.

And get rid of that plywood cover. It'll just be in the way. A good upgrade mod at some point is to add a flexible tray of some sort of stuff to the chuck side of the carriage that catches the chips and keeps the finer dust like swarf from landing on the bed and possibly getting between the bed and the carriage and wearing things badly. Better quality lathes use felt wipers that press firmly against the bed surfaces to guard against this occurring. But I seem to recall that these mini lathes do not have this little nicety. You can either add such wipers and hold down clamps to the carriage or you can add the little traveling chip tray and be sure to wipe the bed down more frequently. Between those two actions it's almost as good as the wipers. Or do all three things and never lose a wink of sleep.
 
BCRider said:
Bertn, looking at your picture again. When you get around to using it try to keep the cutter closer to being over the carriage's footprint on the bed. As shown in the picture the tool is sitting well forward of that direct like of support. When cutting that's going to generate a lot of torque that tries to lift up the tail end of the carriage and bring it away from firm contact with the actual bed. And that's not a good thing on a small lathe. It'll make the machine prone to chatter simply because it does not have a lot of mass to hold the carriage down.

Ideally you would swap out the tool post with one that is more compact and positions the cutting tip closer to the center bolt and keeps the actual cutting tip positioned more centerly over the footprint of the carriage where it sits on the bedways. And if not close to center at least within the footprint of the carriage. That way the forces all extend down directly and force the carraige more firmly to the bed instead of racking it up and trying to tip it.

Along with that always choke the tools in close to the holder. And keep the holders compact as practical. It's all about reducing the "overhang". You always want as short and most direct a path to a direct vertical load. Doing so is even more important on a small and light machine tool.

And get rid of that plywood cover. It'll just be in the way. A good upgrade mod at some point is to add a flexible tray of some sort of stuff to the chuck side of the carriage that catches the chips and keeps the finer dust like swarf from landing on the bed and possibly getting between the bed and the carriage and wearing things badly. Better quality lathes use felt wipers that press firmly against the bed surfaces to guard against this occurring. But I seem to recall that these mini lathes do not have this little nicety. You can either add such wipers and hold down clamps to the carriage or you can add the little traveling chip tray and be sure to wipe the bed down more frequently. Between those two actions it's almost as good as the wipers. Or do all three things and never lose a wink of sleep.
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Thanks for all this advice!
This is just how I got it, it belonged to an older fellow who was into rc boats and planes etc.
It came mounted on a nice solid 3/4 steel plate with a removable nylon/plastic back splash panel.
Pretty heavy dragging it in lol.
There is another tool holder with it and a bunch of other stuff (3 jaw chuck, another 4 jaw one, steady rest, live center, hand full of center drills and some cutters, and measuring tools)
I'll toss the plywood tray thingy and will see if I'll figure out some sort of felt sweeper!

Thx again,
Bert
 
MBiz said:
Based on some research I have done, it appears that Hardinge is a highly rated lathe. Does anyone have experience with this brand?
Thank
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Mostly great, but some of the older models are pretty much impossible to get parts for.

Like, even less parts supply than a ten year old Chinese lathe.

The answer is, "it varies". Changing out the bearings is a non-trivial job, entailing some very expensive bearings, if you can get them at all.
There are several online resources that will help you identify the various models. Unless it is very cheap, or very nice condition, I would suggest being very careful.
 
B_noser said:
I suspect the job of that plywood tray thingy is to protect the ways when changing chucks. Just put it in place when changing chucks.
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If it's for that then great. But the chucks on the mini lathe machines are simply not all that heavy. Still, since it's there it I'd agree that it's worth keeping around for times the chucks are being swapped.
 
trevj said:
Mostly great, but some of the older models are pretty much impossible to get parts for.

Like, even less parts supply than a ten year old Chinese lathe.

The answer is, "it varies". Changing out the bearings is a non-trivial job, entailing some very expensive bearings, if you can get them at all.
There are several online resources that will help you identify the various models. Unless it is very cheap, or very nice condition, I would suggest being very careful.
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Can you recommande a brand that the parts are not to difficult to source?
 
MBiz said:
Can you recommande a brand that the parts are not to difficult to source?
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Not really.

For the most part, unless you buy a new, and still supported model from a dealer, getting parts is near impossible. From the dealer, it's merely difficult and slow. And usually, very expensive.

In the case of Hardinge, they have been making lathes since about the turn of the previous century, so the name alone isn't a sure indicator. Model, and especially, condition, matter a whole lot more.
South Bend Lathes, as a company, died in the 1980's, and the guy that runs Grizzly Tools in the US bought the name and started plastering it all over 'better' import lathes.

If you are shopping for a used lathe, you ARE going to have to accept that you are pretty much on your own. On the up side of that, in some cases, there is aftermarket support, there is ebay, and there are a few rare exceptions, like Logan, where the support is still there, even if the prices can make your eyes water.
Case in point, my Colchester Master 2500. The Gamet bearings, that are in the headstock, are only available from Gamet. Nobody else in the world makes the size. If the bearings go on that lathe, it gets parted out or sold for scrap. Or I spend several thousand dollars on new bearings, and put that money at risk, while installing them, hoping all the while, whatever problem ate them in the first place, has been resolved. The plus side to that risk I took, is that I paid less than I would have for a smaller Chinese lathe, built to a quality spec, rather than a price spec, and I got a lathe that sold for way more than the price of a new car when it was new. So it was worth the risk, to me. And it came with enough tooling and chucks, to fully justify the price I paid, even without getting the lathe.

Try not to get tied up in parts support, either. You can make parts, or have them made. You can fix broken bits, weld cracked castings, etc. All part of the adventure! :)

Honestly, it takes a pretty big screw-up, to break a lathe. It can be done, but it's an effort! Chances are really good, if you buy a new lathe from a dealer at new prices, by the time you actually need parts, they won't be able to get them anyway.
The odds are that a used lathe will serve just fine, but buying a name, rather than a condition of lathe, could end up a time and money pit.

Spend a bunch of time looking at what comes with a new lathe, on various sites, like Grizzly, Harbor Freight, Busy Bee, King Tools, etc., so you know what should be there. Find a lathe that is about the size you think you need, think you can move, think you can provide power for, etc.
I would suggest to you that buying a box of disassembled lathe parts off a basement floor showing signs of a flood (based on a true story!) is probably not a great way to buy your first lathe, if you don't want a hobby of rebuilding a lathe from the ground up.
Look at the general condition of the machine, does it look well cared for? Look at the stuff that comes with it. Look at whether you will need to hire six strong dudes and a carpenter to get it out of a guys basement (also a true story) while the guys wife is at the movies, so she can't see the hole you cut in the floor of the Living room.

Visit the local machine tool dealers. I have had some pretty good deals offered to me, at least one that I STILL kick myself for passing upon, when they had stuff come in that was not really 'industrial' enough to be able to sell to their regular customers. But you will also get to see some of the used gear that is out there, and get a better feel for condition and options.
 
you can also check with your local school board(s) - when the trades went all that stuff got mothballed or sold for scrap. (check machine shops and closing businesses etc.) even if they been beat up by students for a couple decades, like trevj says they are really hard to break!

I wish I was paying attention when GM closed up their prototype shop here in oshawa - it all got sold as scrap!
 
sean69 said:
you can also check with your local school board(s) - when the trades went all that stuff got mothballed or sold for scrap. (check machine shops and closing businesses etc.) even if they been beat up by students for a couple decades, like trevj says they are really hard to break!

I wish I was paying attention when GM closed up their prototype shop here in oshawa - it all got sold as scrap!
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When I took metal shop, about 50 years ago, we had a couple of south Bend lathes that had seen service during WWll, apparently a lot of industrial equipment went that route. When our local High school was closed about 10 years ago, they had the identical ones. :)

Grizz
 
Grizzly Adams said:
When I took metal shop, about 50 years ago, we had a couple of south Bend lathes that had seen service during WWll, apparently a lot of industrial equipment went that route. When our local High school was closed about 10 years ago, they had the identical ones. :)

Grizz
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when I took metal shop about 35 years ago ;) someone got welded into one of the welding booths ..... they changed them all to canvas curtains shortly after that :) hahahaha
 
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