What's new
What's new

Noob lathe selection question

Deude-Mann

Aluminum
Joined
Mar 27, 2021
So I'll ask the question here since:
1. I am interested in gunsmithing as a hobby, already handload and build rifles from components.
2. If I talk about Precision Matthews lathes I won't get kicked in the butt and thrown out the door.

I am looking for a lathe. I am very mechanically inclined, am a very experienced Mech Engineer by trade, and have experience working on cars, building engines and race cars, fabrication, etc.. More importantly, I have friends that are very experienced machinists and can give me advice on what to get.

It has come down to two basic paths:
1. Get a PM or other good quality SE Asian lathe, which even one of my machinist friends who does not like Asian equipment said was a good value. I'd probably get a 1340 or a 1440 with a single phase motor (I don't have 3-phase power available). Some considerations:
- It's going to cost more, at least upfront, than a deal on a good used 'merican lathe (see option 2 below) unless I find a used PM or Jet or the like somewhere.
- Asian lathe quality, though I have been seeing good things about Taiwanese lathes, PM in particular. Gavin Toobe (youtube gunsmith) is ecstatic over his PM 1440GT .

2. Get a used lathe, save some money. Problem is, most stuff that is in this size range or larger is OLD equipment. That does not bother me except for a few things:
- The spindle speeds are too slow for carbide tools (so my machinist friend tells me)
- They are set up for three phase power (I know converters/VFDs are available)
- They need to be checked out thoroughly before buying (to make sure they are actually operational and not bent).
- Parts may or may not be reasonably available
- Headstocks are really long
- Usually only cut inch threads (no metric, unless a gear change can do it).
- I really do not care about the name, as long as it is a good machine. I don't need bro points because I have a Monarch (no offense to Monarch owners).

I am not interested in a big lathe restoration project. I want to make stuff with the lathe. I am willing and able to do things like clean rust off the ways, go through the machine, fix seals, change lubricants, etc.. I do not want to spend hours a week for months just to get it up and running, and give it a nice paint job. I have a large shop to keep/use it in.

So, within the context of gunsmithing, is option 1 the way to go here, or is option 2 viable, assuming I can deal with the issues presented above?

For example, I think VFDs can be used to speed up spindles, but I don't know how far that goes... Can a 1000 RPM max spindle/headstock be pushed to 2000 rpm safely? However some items may be insurmountable, like dealing with a spindle that is way too long or not large enough (diameter).

I can anticipate operations like turning threads on barrels, and cutting chambers, but I don't see myself drilling the barrel caliber and cutting rifling... I'll just buy caliber blanks.

I did search in this forum, but had trouble with the search engine due to words being too short or what not so sorry in advance if I missed a topic that covers the same thing.

Damn... Tried to be concise but it's still a word wall. Just anticipating questions. Thanks
 
OK thanks that is the sort of thing I was wondering about. Seems like all of the barrel blanks I have seen are made out of a relatively non-hard steel (not tool steel, or through hardened) so is most of the cutting done with HSS cutting tools?

Are there any common gunsmithing like operations that would require carbide and high spindle speeds?
 
A lot of the lower rpm older lathes have cast iron or bronze bearings, so pushing them beyond rated rpm can damage them. There are lathes with roller bearings that were setup to customer specs at a low max rpm, it is generally ok to speed them up if needed. My SM is that way, according to tags it is a 1000 rpm lathe, but it was derated because of the raised head, I could change pulleys or add a vfd and run it at 2K, but not with a big chuck or faceplate.

I've only seen 1 PM lathe in person, think it was a size down from what you are looking at, maybe not even in same ballpark. Only thing that I did not like was how the gearbox for threading was setup, limited range of threads then you had to change out gears, with a real funky gear chart. Beyond that it seemed ok, only time will tell.

Most US lathes are setup for cutting inch threads, by changing a gear or 2 they can cut metric. I think there are a few that you can just throw a lever to cut metric threads too. My experience with purchasing used equipment is that they always need a few nit picky simple repairs to get up and running, simple stuff that by your experience description should not be a problem for you. I've only purchased 2 real dogs, parted one out to cover my expense, the other is sitting in my shop waiting to go back together, the parts are there, just need the time.
 
Some of the small (1440 size) English lathes will do both metric and inch threads. I have heard that the metric threads are not "exact" but are close enough for practical applications.
 
Keep in mind that millions of guns were made on those "old" lathes you worry about. Everything can be changed or repaired, even if parts need to be made or adapted.

But your choice really comes down to what you are comfortable with. You're the one who has to live with the decision, so put the work in to figure out your best option.

Jeff

Sent from my SM-G781U using Tapatalk
 
You basically get two choices designing a lathe....either have every conceivable combination in the feed gearbox ,with gears of alarmclock size,or have say less than 12 ratios and change gears.....the box gears can be made strong enough to avoid damage,same with change gears.......I also think that the relationship between metric and imperial is defined exactly by 254/10 or several other combinations
 
I also think that the relationship between metric and imperial is defined exactly by 254/10 or several other combinations

Yes 1 inch is exactly 25.4mm
That is one of the few things that has a short conversion factor that is not rounded.
 
I work in hydraulics, and therefore cut lots of threads, all types of threads.
To get a good start, I think the Southbend 14 linked to would be a reasonable start
Inch\metric switch over is pretty easy on Southbends, lots of info out there.
 
What's the budget ?

I would look for a Takisawa TSL or TAL or if you can find it, for a 30" PINACHO. Both are machines of substantial built with large way surfaces. I would ONLY buy a machine with CAMLOK nose and >50mm t/stock barrel.

Both Harrison and Colchester ( G 600 ) make decent machines of proven design in China. ( PINACHO casts in India, I think...) Bit on the light side but accurate. Once or twice 10 or so years ago I saw some very decent Taiwan made lathes. Besides those ones, while the finish has improved a lot the fundamentals did not.

There are other ( nice ) possibilities but the spindle nose won't be a camlock D 1-3 or 4 .

Take your time, asks tons of questions, get the right tool.
 
What's the budget ?

Take your time, asks tons of questions, get the right tool.

Budget is flexible, say $3K-$6K depending. I agree about taking my time and asking lots of questions. I had a job that had me in a rush to get one initially, but it's no longer needed so I can take it slow.
 
Agree that fle bay SB looks nice. (Post 10)

Good to have a steady and a decent 4jaw chuck, I used a taper attachment often in the limited gun work that I did. Nowadays good to have metric threading.
 
The metric threading is a real complication on lathe selection, on some machines, it can take an hour to switch the end gears, and then return the gear train back, like on a Monarch 10ee, Lodge&Shipley Powerturn, and others.
The more modern machines often have the end train gears stuffed in small compartments, making things even harder.
The lathes of old, had great access to the end train, where the rear cover comes off exposing the entire gear train, with room to put nearly any size gears on.
When the end gears are confined to a small area, the translation gears 120-127 teeth have to be of finer pitch to be able to stuff them in, further complicating that situation.
Some of the later machines are easier to switch the gears, And there are limitation's on threads actually cut on many machines.
 
If you bought a new Asian lathe, would they bring in an 'all-metric' model? In the UK and Australia people are given the option. These machines are built 'metric,' and then bastardised into 'sort-of' Imperial for the US market.
 
Last edited:
Colchester master / student cuts metric and imperial without changing gears.Only time you need to change gears is when cutting less than 8tpi from memory.

I don't know what the used equipment market is like in your area but I hunted for about 3yrs to find something decent used. Thing you find is most of these lorded high quality machines were very expensive when new and no shop buys and expensive machine to sit it in the corner and look at it. They work it hard every day to extract the value from it until it is no longer fit for their needs and move it on. . . . Sometimes to a other company that flogs it even more UNTIL the only value left in the machine is what it's selling for. Face it . . .used machines are cheap because they are a somewhat of a dice roll and unless its clean, under power and you know what your looking for a "good" used machine is probably no better than a new Chinese machine. At least with a new machine you probably have some form of warranty and parts available.

If you want a decent machine sooner rather than later and your not looking for a project to build a project I'd suggest buying new. Most of the tooling will likely be interchangeable between your new Chinese machine and your "ideal" American iron machine so if you stumble across one in the future you can always get rid of the chinese one.

I looked at HSS tooling and spoke to some machinists AND gunsmiths about what I was trying to do. Most the gunsmiths said you can only do our work with HSS tools and you need to learn to grind and home rah rah rah. . . . . machinists pointed me in the direction of good quality ground carbide inserts and they cut very nice threads at 60-90rpm and as a fellow nube I don't have any issues managing a lathe at the speeds these inserts produce nice results. Yes I do have HSS stock in the draw aswell that I can grind for special purposes and it also works well but the carbide works well for 90% of the work and produces consistent results without wasting time grinding and stoning just like it was designed for.

For front a rear spiders it's all going to depend on the machine you get, the length of the headsock and the length of the barrels you want to do. I made rear AND front spiders to get a bit shorter headstock and to have less protrusions to snag your hands on if something went haywire. Seen plenty of different versions of this but one simple way I saw recently was a guy used his standard 4 jaw and put short section of HSS 1/4" rod in the V of the jaw then a short section of 1/4" square HSS between the rod and the barrel running parallel to the barrel. Simple way of getting the barrel to articulate in the chuck with things that you may have on hand or are easy to get.
 
I have the same interests as you and went with an old American machine. I got a Atlas Clausing 4800. It's been a great machine so far and my only issue is the spindle throughbore is a bit too small. It's only 7/8". But I've found ways to get around that using a steadyrest.
 
Just checking in to let you all know I am still shopping, and still reading comments. Thanks for the input.
 








 
Back
Top