I'd like to buy a small lathe

I didn't, but there is a bit of truth in questioning precision on many Chinese products.

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The remaining precision on old American iron like mine can be questionable too. Fortunately if you measure and understand it you can correct or work around (or frequently ignore) many problems. For example you can measure the out-of-squareness of the crossfeed by facing a disk and testing across the far side with an extended dial indicator, which will read double the error. It won't matter for the average pulley sheave, custom spacer bushing or shortened bolt.

Indicating the surfaces of the chuck is another good easy test. I found the worn and unworn sections of my lathe's leadscrew with an indicator, and now cut non-critical threads with the worn section, and critical ones on the tailstock end of a long bar.

The limit to your attainable accuracy is what you can measure, not so much what the lathe can do by itself.

Several home machinist friends talk about having bought a partly assembled lathe kit, or a partly assembled milling machine kit. When they got them home they dissassembled them, did remedial machining and fitting, then did final re-assembly. Had pretty decent machines when they were done

There was a good write up in IIRC Model Engineer some years ago about the purchase/dismantling and rebuild of a Chinese gear head lathe and it was the usual sand in castings, fettling, and proper assembly. The author thought the parts were of high quality and well machined but assembled by monkeys but after all the work the result was decent .

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That's a cynical joke, the machine is sold mostly or fully assembled and "ready to use" but might as well be a kit of parts that need more careful deburring, final fitting and perhaps better-grade hardware. I had to re-tap all the threaded holes in the 3-in-1 combo sheet metal machine I bought used. The original owner had given up on it and I spent a while fussing with its crude adjustments, but now it works well enough for a hobbyist.

In my opinion they are useful machine shop apprentice training as long as you aren't on company time. Identifying and fixing flaws is a valuable skill. Used industrial machinery can have similar problems from wear, and trade school stuff from abuse.

There was a good write up in IIRC Model Engineer some years ago about the purchase/dismantling and rebuild of a Chinese gear head lathe and it was the usual sand in castings, fettling, and proper assembly. The author thought the parts were of high quality and well machined but assembled by monkeys but after all the work the result was decent .

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I generally agree, except that the tee slots on the RF-31 table weren't quite parallel with the dovetails so I had to machine an angled key to mount the vise with its jaws parallel to X. The tee slot needed a bit of single-cut filing to make the key a light friction fit all along its length.

I've heard/read that whatever work can be done at home by mothers tending babies is, for social rather than economic reasons, like the 18th century British cottage industries. The specific job mentioned was casting Toyota tail light lenses.

There is a low level WW2 aerial photo of a burned-out Japanese residential district with the only things standing being a forest of the ruins of drill presses. It was used to justify more firebombing.

They didn't have the DRO version available when I bought it so no regrets possible. I bought a solid-looking Sino brand DRO with 2 glass 5 micron scales to fit it from a local supplier (Accusize) but have not gotten 'round to installing it yet. I installed a similar 3-axis DRO on my mill years ago and that all went okay. It would be better if they were both the same brand because there are differences in operation.

Today I would likely get anything with a decent glass-scale DRO installed if offered at reasonable price. The installation is a bit fiddly. Might consider 1um scales if offered but they'd probably be wasted on me.

Since getting it up on the bench and leveled, I have done virtually nothing to it other than installing the QC toolpost and changing the gearbox oil.

I was in China for a few weeks last fall and did some online shopping for a bunch of tooling for lathe and mill. Quality of everything was generally top-notch, some of it was imported from Japan (Kyocera/Mistubishi insert tooling) or made in Taiwan (5um ER collets). Nice hefty (1.5kg) Albrecht chuck with Imperial R8 shank. I bought stuff with guaranteed accuracy and materials specified. The opposite of the "free shipping" Ali/Banggood junk. Most of the selection in larger industrial sizes though.

I still use my little Sherline occasionally for tiny high-RPM stuff, but mostly not. Another project is to convert that to CNC but it's not going to be great without ballscrews and tiny ballscrews are very expensive.

If I won the lottery, of course, I might choose a different set of tools.

--Best regards, Spehro Pefhany

been using a grizzly 9x20 for about 15 years..

sure works well

Charl

been using a grizzly 9x20 for about 15 years..

sure works well

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What have you found to be its limits of size, accuracy and difficult material?

I've been running a Logan (Wards PowrKraft labeled) built in 1952 for longer than that . It also works very well .

I've been running a Logan (Wards PowrKraft labeled) built in 1952 for longer than that . It also works very well .

I found a used Grizzly at a steal. It was almost new, not used alot. The tooling that was included was worth more than what I paid for the Lathe. expect to spend quite a bit on tooling. You can purchase as you need it. In my opinion buy as much of a lathe as you can possibly afford.

I found a used Grizzly at a steal. It was almost new, not used alot. The tooling that was included was worth more than what I paid for the Lathe. expect to spend quite a bit on tooling. You can purchase as you need it. In my opinion buy as much of a lathe as you can possibly afford.

In my opinion a 10" to 12" lathe with 5C collets is enough unless you -know- you'll need a larger one. An 8" or 9" lathe with 3 and 4 jaw chucks would have handled almost all of my projects. Same some money for the milling machine.