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Tag: Mini-lathe

Tweaking an LMS 5200 Mini-Lathe

  • Mini-Lathe: Adjusting the Carriage Retaining Strips

    The mini-lathe carriage rides on its craptastically finished ways, with a pair of steel strips holding it in place. They’re supposed to be flat against the bed, with a nice oil layer providing a slippery surface. Well, apart from lots and lots of oil, that’s not their as-delivered condition:

    LMS Mini-lathe - carriage front retainer - as received
    LMS Mini-lathe – carriage front retainer – as received

    The rear retainer:

    LMS Mini-lathe - carriage rear retainer - as received
    LMS Mini-lathe – carriage rear retainer – as received

    Adjusting both retaining strips works best without the apron in place, which works best without the leadscrew in place, which requires dismantling the change gear quadrant and messing around with the pieces. Instead, disengage the half nuts (which is how they should be, anyway), remove the two big apron screws, then gently maneuver the apron out of the way off to the right. It’ll rest against the chip pan and hang from the half nuts, but won’t get into any trouble unless you do something stupid.

    Remove both strips, wipe off the excess oil, then align each strip in turn:

    Clamp the strip in place to ensure it’s flat against the underside of the bed way:

    LMS Mini-lathe - carriage front retainer - clamped
    LMS Mini-lathe – carriage front retainer – clamped

    Twiddle the two setscrews until they’re just barely touching the underside of the carriage (thus ready to hold the strip more-or-less in the proper position), snug the three caps screws, test the fit by sliding the carriage back and forth, and iterate until satisfied. I found the setscrews needed quite a bit more than “barely touching” before the cap screws were tight enough, but your experience may differ.

    Maybe 10 minutes of fiddling changed the overall carriage fit from “barely pushable” to “pretty good”, even with the original (lack of) way finishing in full effect:

    LMS Mini-lathe - carriage flat way - detail
    LMS Mini-lathe – carriage flat way – detail

    My lathe has a loose spot a few inches to the right of the chuck, but it’s now reasonably smooth along the entire length.

    Adjusting the cross-slide and compound gibs will definitely improve their disposition, too.

  • Mini-Lathe: Protecting the Compound Leadscrew

    The first of Ted Hansen’s articles (Home Shop Machinist 31.5 – Sept 2012) showed a very nice cap to keep swarf out of the compound’s leadscrew: neatly shaped brass shimstock, held in place with a pair of screws tapped into the compound base.

    Being a big fan of adhesives and low-effort solutions, I applied stainless steel tape:

    LMS Mini-lathe - compound leadscrew cover
    LMS Mini-lathe – compound leadscrew cover

    Perhaps a 3D printed button might be nicer…

  • Mini-Lathe: Articles in Home Shop Machinist and Machinist’s Workshop

    These tables are extracted and slightly updated from the Home Shop Machinist index at http://www.homeshopmachinist.net/resources/article-index/ and the Machinist’s Workshop index at http://www.machinistsworkshop.net/resources/article-index/. I don’t promise to keep this up-to-date, so consider the original sources as definitive…

    Home Shop Machinist

    Article Title Author Page Subject Issue
    Notes on the 7 x 10 Mini-Lathe – Harbor Freight Model 33684 Joe Mroz 41 Hobby Community HSM Vol. 21 No. 4 Jul-Aug 2002
    T-slotted Faceplate for the Mini-lathe, A Sandro Di Filippo 10 Lathes HSM Vol. 30 No. 4 Jul-Aug 2011
    Additions and Modifications to a Mini-lathe Ted Hansen 29 Shop Machinery HSM Vol. 31 No. 5 Sep-Oct 2012
    A+M: Making a Faceplate or Chuck Adapter Ted Hansen 42 Lathes HSM Vol. 31 No. 6 Nov-Dec 2012
    A+M: Apron Upgrades Ted Hansen 49 Lathes HSM Vol. 32 No. 1 Jan-Feb 2013
    A+M: Bed Wipers & Carriage Ways Ted Hansen 52 Lathes HSM Vol. 32 No. 2 Mar-Apr 2013
    A+M: Increasing Torque with a Small Motor Pulley Ted Hansen 28 Lathes HSM Vol. 32 No. 3 May-Jun 2013
    A+M: Upgrading the Tailstock Ted Hansen 34 Lathes HSM Vol. 32 No. 4 Jul-Aug 2013
    A+M: Alignment Essentials Ted Hansen 46 Lathes HSM Vol. 32 No. 5 Sep-Oct 2013
    A+M: A Carriage Travel Stop and Spindle Index Ted Hansen 42 Lathes HSM Vol. 32 No. 6 Nov-Dec 2013
    A+M: Using the Compound Rest as a Milling Slide Ted Hansen 37 Lathes HSM Vol. 33 No. 1 Jan-Feb 2014
    A+M: Milling Setups Ted Hansen 34 Lathes HSM Vol. 33 No. 2 Mar-Apr 2014
    A Fix for the Mini-Lathe Marco Crivellari 22 Lathes HSM Vol. 33 No. 3 May-Jun 2014
    A+M: Compound Rest Improvements Ted Hansen 46 Lathes HSM Vol. 33 No. 3 May-Jun 2014
    A+M: A Quick-change Tool Post Ted Hansen 50 Lathes HSM Vol. 33 No. 4 Jul-Aug 2014
    A+M – Aligning the Cross Slide Ted Hansen 52 Lathes HSM Vol. 33 No. 5 Sep-Oct 2014
    A+M – Cross Slide Improvements Ted Hansen 53 Lathes HSM Vol. 33 No. 6 Nov-Dec 2014
    A+M – Carriage Locks and More Ted Hansen 58 Lathes HSM Vol. 34 No. 1 Jan-Feb 2015
    A+M: The Modular Dividing Head for the Mini Ted Hansen 58 Lathes HSM Vol. 34 No. 2 Mar-Apr 2015
    A+M: A Worm Drive for the Indexing Head Ted Hansen 46 Lathes HSM Vol. 34 No. 3 May-Jun 2015
    A+M: Using the Worm Attachment and Adding a Spindle Index Ted Hansen 54 Lathes HSM Vol. 34 No. 4 Jul-Aug 2015
    A+M: Making Gear Cutters Ted Hansen 56 Miscellaneous HSM Vol. 34 No. 5 Sep-Oct 2015
    A+M: Steady Rests Ted Hansen 56 Lathes HSM Vol. 34 No. 6 Nov-Dec 2015
    A+M: Vertical Milling Attachment Ted Hansen 50 Lathes HSM Vol. 35 No. 1 Jan-Feb 2016
    A+M: A Horizontal Milling Attachment Ted Hansen 52 Lathes HSM Vol. 35 No. 2 Mar-Apr 2016
    A+M: Fine Feeds and Torque Ted Hansen 52 Lathes HSM Vol. 35 No. 3 May-Jun 2016
    A+M: Ball Thrust Bearings and Working with Wood Ted Hansen 52 Lathes HSM Vol. 35 No. 4 Jul-Aug 2016

    Machinist’s Workshop

    Article Title Author Name Subject Issue Page
    A Tailstock Fix for a Mini-lathe Kevin Castner Lathes MW Vol. 24 No. 5 Oct-Nov 2011 32
    Compound Rest and Cross Slide Clamps for the Mini-Lathe Tom McAllister Lathes MW Vol. 26 No. 4 Aug-Sep 2013 28
    Improve the Lead Screw Reverse Latch on Your Mini-lathe James A. Hornicek Lathes MW Vol. 27 No. 1 Feb-Mar 2014 20
    Mini-Lathe Modifications George Overturf Lathes MW Vol. 29 No. 2 Apr-May 2016 20
    My Mini-Lathe Jim Reynolds Lathes MW Vol. 19 No. 3 Jun-Jul 2006 38
    New Saddle Clamps for a Mini-Lathe Carl Byrns Lathes MW Vol. 27 No. 4 Aug-Sep 2014 32
    Quick-change Gearbox for a Chinese Mini-lathe Lex Liberato Lathes MW Vol. 20 No. 4 Aug-Sep 2007 18

    Little Machine Shop tabulates some useful Mini-lathe information:

  • 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.