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Little Machine Shop 5200 7×16 Mini-Lathe: Way Finishing

Ya gotta have a lathe, so I replaced the big South Bend lathe with a Little Machine Shop 5200 7×16 Mini-lathe, because it’s toward the better end of the mini-lathe spectrum and, as Eks put it, it’s not the worst lathe you could own. Having had some experience with the Sherline’s cramped work envelope, the extra two inches of bed seemed like a Very Good Idea.

Ted Hansen’s articles on “Additions and Modifications to a Mini-Lathe” began in the September 2012 Home Shop Machinist and continue to this day, which hints at what’s needed to bring one of these puppies up to contemporary community standards. Unfortunately, HSM doesn’t offer a book or DVD with all the articles in one place; you can buy all the back issues or map the borders of your ethics.

Although the LMS 5200 incorporates many of Hansen’s tweaks (which was a powerful motivation for buying that package; I really don’t need a major diversion right now), it has plenty of room for improvement. In one of his earlier articles, he observes that you may be reluctant to dismantle the lathe, particularly the headstock and apron, because you’re afraid of disturbing the factory alignment. He then says something like “Don’t worry, that won’t be a problem.”

He’s absolutely correct.

Before putting the lathe in service, take it completely apart, wiping off the excess oil as you go, and reassemble it while paying attention to the obvious details. There’s nothing really breakable inside and the thing will run much better after a simple laying-on-of-hands “repair”.

The condition of the ways was … disappointing, even though I wasn’t expecting much. As nearly as I can tell, final way alignment, done by precision grinding or  hand-scraping for spendy tools, consisted of a few passes with a hand-held angle grinder.

The tailstock doesn’t really need a sliding fit, because it operates while clamped to the bed; the flat way is rugged:

LMS Mini-lathe - tailstock flat way

LMS Mini-lathe – tailstock flat way

Its V-groove isn’t much better:

LMS Mini-lathe - tailstock V-groove

LMS Mini-lathe – tailstock V-groove

The compound ways are sliding joints, albeit with few points of contact:

LMS Mini-lathe - compound way

LMS Mini-lathe – compound way

The chromed (!) protractor dial has what Eks calls a “used car polish”: high shine over deep scratches.

The cross-slide ways seem to be slightly concave, with a single contact point on the far left end and a few more on the right:

LMS Mini-lathe - cross-slide way

LMS Mini-lathe – cross-slide way

The carriage flat leaves much to be desired:

LMS Mini-lathe - carriage flat way - detail

LMS Mini-lathe – carriage flat way – detail

That red patch toward the left isn’t left-over scraping blue:

LMS Mini-lathe - carriage V way - detail

LMS Mini-lathe – carriage V way – detail

I have no intention of spending all the time required to hand-scrape those things, Moglice seems like overkill (and has an imposing minimum thickness), and Turcite requires reasonable surface finish (and adds considerable thickness, too).

I’m mildly temped to apply a thin layer of good ol’ JB Weld epoxy, just to fill in the valleys and improve the contact area, but not right now.

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  1. #1 by rkward on 2016-07-04 - 09:30

    It’s a spendy little lathe that looks good on the website, but your closeups show the usual Chinese quality. I’ll be interested to find out what you think of it when compared to your SB. Especially in the “hi-torque” department. I’m sure you’ll test it out a bit to see what it takes to stall it.

    • #2 by Ed on 2016-07-04 - 10:49

      An absolutely unimpeachable source says the factory producing all mini-lathes ships every unit they build: they have no QC rejects. Each OEM purchases as much quality as they can afford and high-end OEMs can specify a custom color.

      The source recommends avoiding red mini-lathes…

      • #3 by rkward on 2016-07-04 - 11:20

        Pretty much figured it worked like that; kinda like legal defense. I happen to have the red Micro-Mark version which was specifically listed as “true-inch”, going on 6 years or so now. Is has had a lot of use and has held up well but I really push it most of the time and could use a larger and more powerful lathe, same as the mill. But no doubt I have gotten my money’s worth out of them. According to their site now they continue to improve the quality and features … and no longer paint them red. I have seen the HF version up close and would not consider them in the running at all.

  2. #4 by Joel on 2016-07-04 - 10:33

    I was thinking of downsizing from my Enco 13×40 to something like this so I’d have a little more room in the shop. Maybe I’ll stick with what I have. Thanks for the review.

    • #5 by Ed on 2016-07-04 - 10:55

      I think it’ll be perfectly usable for my projects. The motor speed control is great, the insert toolholders are great, but the size and overall feel are definitely down from that big ol’ cast iron monster.

      More observations & tweaks to come… [grin]

  3. #6 by Red County Pete on 2016-07-04 - 11:26

    My refurbished 12 x 36″ Atlas/Craftsman is looking better every day. When I get beyond more pressing projects, I need to install the Leeson 1725 RPM motor (it was rebuilt with a 3450 motor; too fast for my tastes).

    • #7 by Ed on 2016-07-05 - 14:23

      The speed control definitely works better than that three-speed stick transmission on the SB.

      I just crunched three wires in the chuck, dialed for slow-mo, and got a foot of nicely twisted cable with no hassle; much easier than my usual three-handed drill fumbling.

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