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CARE AND LUBRICATION OF MYFORD SERIES 7 LATHEShaythornthwaite.com/184 Myford Lubrication.pdf · CARE AND LUBRICATION OF MYFORD SERIES 7 LATHES David Haythornthwaite gets to the bottom

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  • CARE AND LUBRICATION OFMYFORD SERIES 7 LATHES

    David Haythornthwaite gets to thebottom of a question botheringmany Myford lathe owners.

    OVERVIEW

    I have been asked by one or twoMyford owners, the correct lubri-cation to use on the lathe, andindeed I have also been unsureabout some lubrication aspects.At the recent (last ?) MyfordSpring Show, I asked the techni-cians for clarification about theoils to use and the lubricationpoints to look out for. I hope thatthe information gleaned will helpother owners.At the time of writing this article,Myford have recently gone intoLiquidation and all the stock ofspares are now available fromRDG tools. Where appropriate,however, I am still quoting origi-nal Myford part numbers.

    General CareWhilst this article is mainly aboutlubrication of your lathe, a fewwords about general care of thelathe may not go amiss. Follow-ing a few sensible rules in the dai-ly operation of any lathe will helpto keep it in an almost new condi-tion.1. When machining irregular

    shaped items, always turn the latheby hand before engaging powereddrive in order to ensure that thework has full clearance from themachine and will not damage ei-ther the lathe bed, slides or toolholders.

    2. Keep the bed and working partsof the lathe clean and free of swarf,particularly after machining Brassor Cast Iron.

    3. If the lathe is to be left in a dampatmosphere, ensure that all un-painted surfaces are liberally coat-ed with rust preventative orpreservation oil, particularly thebed and slide surfaces.

    4. If abrasives or grinding wheelsare used either on the lathe or near-

    by, then protective measuresshould be taken to protect the latheand in particular the lathe bed fromharmful abrasive dust which other-wise could become embedded intothe slideways.

    Cover your lathe after use to pro-tect from dust and airborne con-taminants. Myford used to offerwaterproof, fitted covers PartNos 11574 or 11575 dependingupon the bed length. Presumablynow available from RDG tools..

    Lubrication of the LatheTwo lubricants are recommendedfor regular use on the lathe. Theseare :-

    1. Esso Nuto H32 Oil A thin,hydraulic oil for Headstock lubri-cation and to lubricate the majorityof rotating parts. Myford Part No80024. We shall call this simplyH32.

    2. Esso Febis K68 Oil a heaviersticky oil for use in the gearbox,on gears and preferably on slide-ways. We shall call this K68.

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  • Note :- the prolific lubricationpoints on your lathe are not greasenipples, but are oil nipples. Yourlathe does not require grease in itsregular maintenance, but requiresoil applied through the use of aMyford oil gun. If you boughtyour lathe new from Myford, thenan oil gun will have been suppliedwith the machine. Many of theolder oil guns, whilst being per-fectly serviceable, did have an un-fortunate tendency to leak oil allover the place. Myford recentlyoffered a much improved oil gunas illustrated in Photo.2 which hasgreater capacity and is guaranteedleak proof. Myford Part No 15472.Safety Note :- The latest lathemodels carry a safety warning as

    illustrated in Photo.3 warning thatyou are advised to isolate the mo-tor and ensure the lathe is at restbefore opening any of the latheguards for maintenance. Whilstsome older lathes may not carrythis warning, it is important thatthese precautions are carried outprior to opening any lathe guardswith the possible exception ofchuck or splash guards.Headstock LubricationThe most important lubrication pointis the headstock main (front) bearing.This bearing is a tapered plainbearing for the lathe spindle and thespindle is lubricated by a spring load-ed felt wick which sits in a small oilreservoir and bears onto the mainspindle through a slot in the bearing,thus applying a continuous smear ofoil whilst the lathe is running.Photo.6 illustrates the oil cup whichmust be filled with H32 oil twice aday if the lathe is being run continu-ously.Whilst using the lathe it is good prac-tice to monitor the main bearing tem-perature occasionally with the hand.

    The bearing will run warm, butshould the bearing start to becomeoverly hot, then the availability of oilin the cup should be checked. If a ful-ly lubricated bearing still runs hotthen the adjustment of the main bear-ing should be checked.The rear bearing consists of twin an-gular contact ball bearings whichneed oil lubrication with H32 oil.Apply the oil gun and give twopumps to the nipple shown in Photo.7on a daily basis.

    The coned V belt pulley which runson the main lathe spindle gives 4 se-lectable speeds in direct drive bychanging the position of the belt.When the lathe is run in direct drive as opposed to running in back gear the cone pulley is locked to the mainspindle and lubrication is not a partic-ular issue.However, when the pulley is discon-nected from the lathe spindle and theback gear is engaged, the pulley isthen being driven by the belt at about8 times the speed of the main spindleupon which it is rotating. Efficientlubrication of this pulley is crucialwhen running in back gear and the oilgun must be used on the oil nipple

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    3 4

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  • shown in Photo.8 until oil just be-comes visible on the joint at the back- gear end - of the pulley. You mayhave to rotate the spindle by hand inorder to see and gain access to this oilnipple.The gears of the back gearmechanism should be sparingly lubri-cated with K68 oil as illustrated inPhoto.8 using an oil can. K68 is asticky gear oil and will therefore re-main in contact with the gears betterthan wouldbe achieved by the thinner H32 oil.The final oil point on the headstock isin the shaft centre of the back gearengagement handle as shown inPhoto. 9. This is easily missed but isimportant as it lubricates the backgear layshaft. When the back gear is

    in use this shaft should be lubricatedby the oil gun twice daily.

    The photographic illustrations are tak-en from a variety of lathes, but all thelathes illustrated incorporate thequick change gearbox and a poweredcross slide. Lathes with manual geartrains and without powered crossslides will vary slightly in their lubri-cation requirements, and these varia-tions will be mentioned later.Gear Train & GearboxLubricationThe method of driving the leadscrewfrom the headstock spindle will de-pend upon whether or not the lathe inquestion incorporates a quick change

    (Q.C.) gearbox and indeed whether ornot the Myford metricconversion quadrant has been fitted.However the photos in Photo. 10 andin 11 illustrate the basic philosophyof lubricating the gear train whichev-er type is involved. Both the tumblergears as shown in Photo.10 and themain gear train as in Photo. 11 haveto be lubricated in two separate ways.The studs on which the gears are run-ning must be lubricated with H32 oil,by oil gun if oil nipples exist on thestuds, or by oil can if oil nipples arenot present as in some older ML7lathes or with the metric quadrant inuse. The actual teeth of the gearwheels require oiling sparingly withK68 oil using an oil can. Just suffi-

    9 10

    11 12

    7 8

  • cient oil is required to eliminate thefriction without splashing oil all overthe surrounding areas. For lathes fit-ted with a Q.C. gearbox the gearboxrequires lubrication entirely with K68oil which is a gearbox oil.Photo. 12 shows the gearbox on oneof the latest Super 7 Plus machines.The gearbox features an oil reservoirin the lower half of the gearbox, andthis may be drained through the drainplug illustrated in Photo. 13. The fill-ing / level plug can then be removedand the gearbox filled to the level ofthe plug with K68 oil. It may be filledto the level plug through the large ap-erture if preferred. From time to timethe gearbox should be drained,flushed out with thin (H32) oil andthen refilled with the correct K68 oil.On thetop of the gearbox are two oil cups sothat top up oil (K68) may be added bythe use of an oil can and as theoil cups are over the gear shafts, theoil will circulate over the gears.In Photo.14 an older Q.C. gearbox isillustrated, and this has identical lu-brication requirements. However the

    top up points have oil nipples in placeof the current oil cups and if the own-er has only one oil gun, as islikely, it will undoubtedly be full ofH32 oil. However the more modernoil cups are available for a fairlynominal charge (Part No. 65009) andas both the oil nipples and the oilcups are a press fit into the gearbox,changing to the modern style is fairlyeasy. This seems a better solutionthan draining and refilling an oil guneach time it is necessary to lubricatethe upper gearbox. Photo. 13 illus-trates the reservoir level and drainingpoints.Leadscrew LubricationPhoto. 15 shows the end supportbearing which must be lubricatedwith H32 using the oil gun. Once perweek should prove sufficient. Onlathes without a Q.C. gearbox, thereis an identical leadscrew supportbearing on the left hand side whichshould be similarly treated. The lead-screw itself should be cleaned withparaffin and a stiff brush from time totime and oiled with K68 from an oilcan. It is important for the

    accuracy of the leadscrew to keep theleadscrew thread both clean and welllubricated.

    Saddle & Apron LubricationThe saddle is lubricated through twooil nipples situated as shown inPhoto.16 and 17. As illustrated,the rear shear is lubricated through anoil nipple situated on the rear edge ofthe saddle and it is hard to seefrom the top of the saddle how thismay be effective. Photo. 18 showsthe saddle inverted and illustrateshow there are long grooves on theunderside of the saddle to distributethe oil evenly over the lathe bed slideways. The front shear is not lubricat-ed by the similarly placed nipple atthe front, but is lubricated by thenipple placed on the top of the saddle.H32 oil is used for the saddle, but themore sticky K68 may be foundto stay on the slides better if you dohave two oil guns.The saddle incorporates a felt wiperon the edge nearest to the headstockin order to retain oil inside thesaddle and to stop swarf from becom-ing trapped underneath the saddle andcausing wear to the lathe bed.

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    13 14

  • From time to time, the cover and wip-er should be removed by removingthe four retaining screws. If theexisting wiper is still in good condi-tion, it may be cleaned and soaked inH32 oil. The seating face on theedge of the saddle and the retainingcover should be cleaned with paraffinand the, oil soaked, wiper refitted.It is a good idea to replace the feltwiper from time to time and this isbeing done in Photo.19 where a newfelt wiper part no. A8735 is ready forfitting. Older ML7 lathes will take adifferent design of wiper part no70/1328. New felt wipers should besoaked in oil prior to fitting. Keepingthe lathe bed clean and clear of

    swarf will help to extend the life ofthis part as well as the lathe bed itself.Saddle Apron LubricationThe lubrication points on the apronare illustrated in Photo 20 and as it isalways helpful to understand wherethe oil is going, Photo.21 shows theapron removed from the lathe to illus-trate the mechanisms that the aproncontains and the lubrication required.This apron is from a machine withpowered cross slide and machineswithout this facility will have a sim-pler style of apron and fewer lubrica-tion points. The top oil nipple on theedge of the saddle plate lubricates thecross slide drive clutch spindle withH32 via the channel on the underside

    of the saddle shown in Photo. 18. Theother two oil nipples also lubricate thecross slide drive mechanism with H32through oil paths drilled into theapron casting. Obviously thisarrangement differs on lathes withoutpowered cross slides.It is easy to miss the fact that the sad-dle carries an oil reservoir whichshould be filled with K68 gear oilthrough the level plug just to the leftof the quick traverse handle. This lu-bricates the quick traversemechanism.Tailstock LubricationThe sliding barrel and thread of thetailstock are lubricated with H32through the two oil nipples shown in

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    19 20

    17 18

  • Photo. 22 whilst the thrust bearing onthe Super 7 is lubricated through theoil nipple in Photo. 23 again withH32Cross Slide and Top SlideLubricationThere are no formal lubrication pointsfor the slides on the cross slide andthe top slide. These are best lubricat-ed with an oil can from beneath withK68 oil. Withdraw the slide as far as

    possible to reveal the sliding surfacesas illustrated in Photo. 24 and applythe oil. Using the thicker K68sticky oil will retain the oil betteron the sliding surfaces, but H32would be quite suitable if preferred.K68 should be liberally applied to theslide lead screws on a regular basis.The cross slide should be lubricatedin a similar manner. With just a littlecare and attention, you can extend the

    life of your lathe by many years, andthe number of Myford lathes whichare still in use and producing qualitywork after more than 50 years con-stant use illustrates the potential ofthese superior British lathes. It isworth taking time to correctly lubri-cate your lathe and it will pay divi-dends in the long term.

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