Rebuilding a cheap lathe

These are very small and light for carbide inserts. There's a high level of convenience in them, but they want faster speeds and larger depths of cut

@Jake M

I am sorry, but I have to take issue with that blanket statement. I have, from day one, used carbide insert tooling with my 7x and continue to do so. I have turned mulitple different materials, all of it under 1000rpm (mainly 400 - 600rpm) and never had a problem with the inserts or the ability to turn anything, including 316 stainless. I also use cutting depths from a half thou' through to 118 thou', hand feeding the deeper cuts.

Sure, push people away from carbide if you have a valid reason like expense or that person is brand new to turning and would likely be frustrated if they kept breaking inserts whilst trying to turn something, but do not knock carbide on a machine that has been proven to handle it.

In fact, I would go so far as to caution anyone brand new to using a lathe to be aware that yes, carbide tooling has its place, but research and understand is required before buying into it. Learning basic turning with HSS tooling first is a good idea as is learning to grind and hone HSS tools.

Personally, I was taught the "Stone "n" Hone" method once I had learnt the basics of HSS tool grinding. Id-Est, grind the tool on a grinder stone, then hone (polish) it on an oil stone.
 
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@Jake M

I am sorry, but I have to take issue with that blanket statement.

I don't take issue with being taken issue with, but I do think that was an unfair snip of my last paragraph.

One thing I might toss out, if you need tool bits to even try this out- These are very small and light for carbide inserts. There's a high level of convenience in them, but they want faster speeds and larger depths of cut... If it's in your wheelhouse at all, especially to get going and feel it out, I'd grab a couple of high speed steel blanks and grind some basic tools. Or if something came with it, run with that. They all can work, just maybe easier coming up to speed with a ground tool that's dead sharp, than an insert tool which won't be.
 
I don't take issue with being taken issue with, but I do think that was an unfair snip of my last paragraph.

@Jake M

It was not an unfair snipping given how most people would take it as a blanket dismissal of using carbide tools/tooling on a 7x.
 
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@Jake M

It was not an unfair snipping given how most people would take it as a blanket dismissal of using carbide tools/tooling on a 7x.
Honestly, I think I can see how it could be read both ways.

I'll be frank, I've been tending to get a better surface finish with HSS (it seems I have got lucky with my attempts to freehand a teensy radius with a stone ;)) but then I'm a rank, wet behind the ears noob, and the feel for appropriate feeds (manual) and speeds hasn't really bedded in, I'd expect.

The latter admission though is something that would be common with most beginners, so maybe HSS is a better way to start for a beginner on a small, relatively unrigid lathe.
 
Lots of guys on here know more then me, but I typically use kerosene for cleaning things like this. Less risk of harming plastics that it might get on. I would oil the parts after you clean them. The ways of the machine should get coated in way oil and everything else in spindle oil (usually a 10 or 20 weight oil - not motor oil).

As far as number 4, make sure you take off rings, watch and long sleeves before running the lathe. Keep yourself away from moving parts.
Thanks for the info. I'll pick up some spindle oil and use that.

I don't wear jewelry of any kind, so that's not an issue. I do work with power tools rather frequently and in my time I've known more than a few people who didn't respect the power that power tools have and they paid a price for that. I know one guy who cut the tip of his thumb off with a table saw, another fellow who drove a nail into the bone in his leg with a framing gun, and another fellow who lost his entire arm to a circular saw. There was an electrical short, he got shocked and his right arm, which was holding the saw, jerked the saw up into his left arm. The arm was so messed up that the doctors amputated it.

In short, I'm extremely conscious of safety. I'm not familiar with all the safety precautions one should follow when working with a metal lathe so I very much appreciate the tips on that.
 
@Eric S Dunn

Whelp, where to start...

Given it is a 7x family lathe and a small 7x at that, I would look at what you will actually spend on replacing / upgrading / changing BEFORE going down that route.

As lathes go, a 7x can be a daunting prospect if you are not aware of the fundamental issues most people find with them, such as lack of rigidity, lack of power and the restrictive size of them.

That said, they are a good lathe to "cut your teeth on". Not too small, not too big, not exactly cheap, but not expensive.

There are is a laundry list of things you can do with these lathes but the big three are going to a Brushless motor and controller (kits are available), going with an Electronic leadscrew (kits are available) and going with a 16" bedway conversion (New bed/leadscrew/chip-tray).

With the headstock, an upgrade to a 4" flange spindle if it is only a 3" flange, Angular Contact spindle bearings, brass gibs, extended cross slide travel mod, Quick Change Tool Post & Holder (Most go with a wedge gib Quick Change Tool Post).

If you want to get an idea of just how deep some, myself included go into rebuilding / upgrading / modifying the 7x platform, check out this (ongoing) thread on a 7x rebuild I am doing (<<< LINK)

There are a few members on here with 7x lathes, all will say roughly the same thing about headstock bearings, spindle and bedway length.
I appreciate the tips. I'm not looking to upgrade the thing, just to get it running. If I find that I enjoy machining things, I'll go ahead and pick up the PM I've been thinking on. Most of the things I want to machine will require a larger machine than 7x10. If I manage to get this one running for a few hundred bucks and get some experience with it, I'll consider that a win.
 
I'm a big fan of transmission fluid for cleaning up crusty machines. Cleans everything, harms nothing and leaves a nice shine. Kerosene works well also. As I understand, on those 7x lathes the gears are the weak link.
Are you referring to the gears for cutting threads? If so, it's not a problem. I didn't get them with the machine. No matter, a tap and die set works fine for me.
 
You've got two different double edge swords going on there.
The first being that making the first project on the lathe into a "finished" product is really putting the cart before the horse. Lathes (any lathe) works best after you learn it's character. Unlike wood, these see a LOT of cutting forces, so stuff "moves". Tool selection and/or grinding is equally as important as wood turning, but ten thousand times more options (give or take...).
The second one being that the little mini lathes are inherently made "just good enough", and sometimes not even that. They often need a lot of lovin' to get them up to a standard that will allow you (not the lathe) to make decent parts on. (Or even good to excellent parts, I'm not knocking 'em that hard at all). Many owners find that it takes more investment to bring the lathe up to the standards they want than it did to buy it new in the first place.

Should that stop you? No, absolutely not. But you've got to keep both of those things in mind. For a test thing, to see if you're interested, you've got a great thing there. You've just got to have reasonable expectations, otherwise you're gonna spend an hour with it and loose all intrest in metalworking.



Kerosene or WD40 (which is very kerosene like) work well.
Degreaser like simple green/purple power/ one of those things? Those are pretty fine, they're well safetyfied, but you wanna be able to rinse stuff after. By that, I mean a clean damp rag to follow the cleaner, dry, oil.....



Yes. Bare metal wants to be oiled. Some oil is better than no oil, and on a machine like that, where it can be made to work fine, and even if you do get after that and make it "perfect", it was never built to be an heirloom piece, that advice alone might be plenty good enough. If this is an incidental sideline for you that will get used some, or even if it turns out you use it all the time, you could do better. The first is to stay out of anything automotive. That's not your friend here. Tractor stuff too, none of that. An ISO 46 or ISO 68 hydraulic fluid (R&O or AW would be fine) labeled as such, and NOT lableled for tractors, splitters, or any specialty purpose would make a much more appropriate oil for such things. A gallon would last years. And you don't say what woodworking you do, but if it applies, it'd be pretty ideal for metal slides, trunions and mechanisms on wood working machines that specify oiling as well.



It's a used machine, at a price point that makes several of it's individual components worth more than the whole thing. While I do very much believe in and practice that approach to repairing and maintaining almost anything... I'm not spending 30 bucks on brushes for an off shore angle grinder that costs 35 dollars to replace. These are not hard to disassemble. Evaluate anything obvious for feasibility, but plan on a second teardown. Several things need a lot of tearing apart to get to, but the whole teardown is not bad enough to warrant precautionary investments until you know what you have.



I'd bet that if you take that lathe to pieces, get all of the sticky parts unstuck, get all the sliding parts un gunked and un rusted, and get to a point where you can say that this is possible to piece back together, by then you'll have questions...

One thing I might toss out, if you need tool bits to even try this out- These are very small and light for carbide inserts. There's a high level of convenience in them, but they want faster speeds and larger depths of cut... If it's in your wheelhouse at all, especially to get going and feel it out, I'd grab a couple of high speed steel blanks and grind some basic tools. Or if something came with it, run with that. They all can work, just maybe easier coming up to speed with a ground tool that's dead sharp, than an insert tool which won't be.
Appreciate all that info. I picked up some HSS blanks this past weekend (in anticipation of getting this lathe up and running). I've watched a few videos on how to grind the tools, but haven't had a chance to do so yet.

I don't know whether I will end up using a lathe a lot or not, which is why I'm really happy that this little one came along before I sank any major bucks into this. I started my current hobby (astrophotography) the same way, small and cheap, then bought something else, then something else, and so on. And while I love astrophotography, there are some inherent limitation in that hobby, like the need for clear skies. Because of those limitation, I don't get to do it that much ... which is part of the reason why I'm out looking for another hobby. This seems interesting to me (as well as useful) so here we go.
 
So, I know I’m going to be berated for saying this, but…
I have 3 lathes, one of which is a 7x10 Chinese mini lathe.

The lathe you have is a serious project in and of itself. The work to get it correctly working is usually extensive. An awesome learning project but…. The working window on the 10 inch length makes using it almost impossible for anything but the smallest of parts.

If you’re going to invest your time and new knowledge to make this machine run correctly, I would recommend purchasing a longer lathe bed from Little Machine Shop.

I think you would find the usefulness of the small lathe much greater with a longer bed.

Just my 2 cents.

John in Mn


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I don't take issue with being taken issue with, but I do think that was an unfair snip of my last paragraph.
Your comment, even as snipped, is completely valid. Carbide needing higher speed and greater depth is common knowledge.
 
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