First Lathe: Small Greaves Klusman Gearhead
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    Default First Lathe: Small Greaves Klusman Gearhead

    Hello everyone, my name is Jake and this is my first post here. Thanks for all the great contributions that make this such a great community!

    I have been hunting for a lathe for the last year or so. My aspirations have shifted and grown during the hunt from the initial import mini lathe to an older SB 9C, or a Logan/Atlas. Then, thinking power cross feed would be pretty cool, I looked more at the 9A/9B and various other contenders. After getting annoyed by the consistent high prices for these types of lathes in the Pacific Northwest, I nearly pulled the trigger on a 13 x 40 Southbend, but it just didn't feel like a solid deal.

    Then I found the following ad on Thursday morning, which is literally a 15 minute drive from the mill where I work. I emailed 17 minutes after it was posted and was making a test cut on it within the next 30 minutes.

    Needless to say, it's mine now.


    The Good
    • It runs!
    • Single Phase
    • Everything appears to work as it should
    • It has a QCTP with a small handful of tool holders
    • Power feeds work great in both directions for carriage and cross feed
    • Tailstock and quill move freely
    • Integrated thread dial in the carriage bridge is cool
    • Gear shift and back gear control levers work great
    • The gears in the gear head look like new


    The Bad
    • No TA
    • No 4 Jaw nor Faceplate
    • No Rests of any kind, Live centers, drill chucks, etc...


    The Ugly
    • Well, it's in a converted barn-shop, so there's that...
    • Someone replaced the spindle bearing oilers with grease zerks. 😬
    • There is significant slop in the carriage traverse hand wheel.
    • It's missing the thread and feed chart.
    • The gear train cover has been welded once, but looks like it can be cleaned up and made respectable once more
    • It's real, real dirty.


    The Plan
    First and foremost, is getting it to the shop. It is still tucked away in the back of the seller's shop, under power at the moment. I will post some pictures of that adventure when the time comes. He has a forklift for loading and I have access to a flatbed and forklift for loading, so it should be fairly trivial to get it home, all in one piece, though the headstock is massively heavier that anything on the tail end so rigging will be "fun".

    The next step will be getting proper oilers installed on the spindle bearings. This will involve opening up the gear case, marking and pulling the spindle caps, marking and measuring the shim packs, lifting the spindle out and thoroughly cleaning out all the grease, checking the surfaces for major issues and cleaning everything up as best I can before reinstalling and checking the spindle bearing clearance with a lift test. Hopefully all is well and I can move forward with properly oiled bearings without too much trouble. I can't imagine why someone would grease these, but I don't think it would cause too much grief with a max spindle speed of 410 RPM. Hopefully it was a folly to switch to grease and not an attempt to hide sloppy bearings...

    While all the above is transpiring, I'll be treating all the painted surfaces to a nice bath in Purple Power and I'll clean up all the dirty oil on the ways and get some fresh way oil in place. There was very nearly zero rust on the lathe, but I'll go over everything little by little and see what's what. I haven't even measured the swing yet, so am not entirely sure what size the lathe is yet, though the 45 speed screw cutting gearbox suggests it is no larger than an 18. I suspect it is a 14 or 16, but I'll know soon!. As I'm cleaning the ways, I'll hunt down the serial number and see if we can figure out a rough manufacture date, as well. Im guessing mid to late 30's? The double V-belt motor drive is suspect to me...

    Since it is under power and working well enough as is. I plan to waste no time in putting this sucker to use. I hope to draw off of some of the expertise here to get it cleaned up and making good cuts in the near future, and I'll document as much of the process as is practicable. I'm no John Oder, but I prefer not to cut corners and enjoy doing things as properly as I can given my limited capabilities. This means documenting the state of the machine and working through the functions as designed and as found as I move along. Hopefully this little journey will be a worthwhile endeavor for me and a fascinating read to some of you. Many thanks for all I've learned about the heritage of this old girl from you folks thus far; I look forward to the journey that lies ahead.

    Cheers!

    - Jake
    Last edited by Jake_G; 02-24-2020 at 09:03 AM.

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    I have its big brother 20" heavy - in horrible condition. Here is my thread - a project that very likely will out live me

    20" Heavy Greaves Klusman

    If I don't have a 14 page for you I will make one and post it

    Here you go

    gk-14-gear-head-twenties.jpg

    Here a larger thread chart on my 20 heavy - may not be exact for smaller lathes - I don't think the 14 will have the sixth hole for the left hand lever - or the top row shown in this photo

    100_1980.jpg

    In case not known, these creatures have forward and reverse clutches - controlled by that enormous lever - maybe including the one on the right hand bottom of apron.

    You may be able to still read spindle speeds - on the riveted on brass arc segment above the notched arc segment for that big lever. With that modern (speedy?) motor I would imagine yours goes way faster than original. My 20 Heavy tops out at 300

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    Good find Jake..be careful you don't break anything and it should last for a good long time. Not a bad idea to hand pull a spindle turn to be sure you have the levers/back gear right so not breaking anything getting used to levers.
    Solvent and oil rag wipe, and hand picking out all the chips is good..WD spray can and a air blow job is bad.

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    Quote Originally Posted by johnoder View Post
    I have its big brother 20" heavy - in horrible condition. Here is my thread - a project that very likely will out live me

    20" Heavy Greaves Klusman
    John,

    Your saga on the 20" Heavy has been awe-inspiring!


    If I don't have a 14 page for you I will make one and post it

    Here you go
    Thank you!


    Here a larger thread chart on my 20 heavy - may not be exact for smaller lathes - I don't think the 14 will have the sixth hole for the left hand lever - or the top row shown in this photo
    Indeed, mine is missing the 6th hole and top of the chart. It seems that the feeds are listed in turns per inch at a ratio of 5.4:1 compared to threading. That's interesting, and I suppose quite common?


    In case not known, these creatures have forward and reverse clutches - controlled by that enormous lever - maybe including the one on the right hand bottom of apron.
    Yes. I need to identify the style I have. Are they cast iron like frictions the apron bevel gears? Here is a shot of the upgrade found on later machines:

    Originally posted here
    I appear to be missing the lower rod the would control the clutches from the apron, but I have a casting to support it at the tailstock end of the bed. I'll have to inspect what other bits are missing/present. Obviously I will have to get creative when it comes to replacing anything that is missing.


    You may be able to still read spindle speeds - on the riveted on brass arc segment above the notched arc segment for that big lever. With that modern (speedy?) motor I would imagine yours goes way faster than original. My 20 Heavy tops out at 300
    Yes, the spindle speed readout is in good shape and maxes at 410 RPM with whaterver motor it was equipped with from the factory. The top mount looks original, but the motor mount (and obviously the motor) are retrofits. Do you think the V-belts are adders, as well? Did GK ever get away from flat belts?


    Good find Jake..be careful you don't break anything and it should last for a good long time. Not a bad idea to hand pull a spindle turn to be sure you have the levers/back gear right so not breaking anything getting used to levers.
    Solvent and oil rag wipe, and hand picking out all the chips is good..WD spray can and a air blow job is bad.
    Good advice. Thanks. I will take literally all I can get.

    Can anyone explain what the hand wheel on the aft end of the quick change does? Is that a way of manually disengaging the lead screw when using the feed rod only?

    Thanks again,

    -Jake

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    Clutches .... Older have clutch linkage entering left end of head stock. Newer have clutch linkage entering right end of head stock. My older clutch assemblies look just like the later ones as far as how they are made. The linkage is mostly what changed - the later has it cleverly routed thru middle of input shaft, while the older has it laying around in floor of head stock

    My 20 heavy just has a flat belt pulley - apparently the motor and other pulley got lost along the way to living out doors in the eastern TN woods

    Or maybe it never got its own motor and was a line shaft machine

    Here is the later 20 Heavy that got scrapped in CA - a shot of the newer linkage

    015.jpg

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    Quote Originally Posted by Jake_G View Post
    The next step will be getting proper oilers installed on the spindle bearings.
    Alemite Zerks are, in fact "legit" for supplying OIL as well as grease. Check with the PO. If he has an oiler fitted to match a Zerk, it might NOT be full of grease. Mind, I am not he who knows if it needs adjustable drips with the sight-glass dispensing reservoirs, "Lunkenheimer" design, ISTR, though Gits also makes them still, yet, and MMC carry them.

    While all the above is transpiring, I'll be treating all the painted surfaces to a nice bath in Purple Power.
    Suggestion. First, or perhaps instead-of.. grab a cheap "waterless" hand cleaner. The sort WITHOUT pumice/abrasive. I use "Goop". Slather than on, Day One and leave it. Day two have at it with chip brushes and one of those little round-headed shoe polish dauber brushes. Follow with ATF, Diesel fuel, WD-40 only if you are that wealthy.

    DO NOT go wild with brake-kleen, carburettor cleaner, injector cleaner, nor "just yet" even Acetone.

    You may be amazed at how much crud, impacted chips, and even varnish comes off the machine-tool, just as it does yer hands, with the waterless cleaner KEPT "waterless". Also with near-zero add to risking creation of MORE rust in hidden places, and with no damage to paint as is not already perished.

    Once you "have full sight" of what's been hidden, I'd stop with the cosmetics, focus on function, do a deeper assessment of what else it needs.

    Paint can wait, and it is USUALLY best that it is MADE to wait.
    You'll be ahead if you put ALL tear-downs on "hold" as well.

    It is intact and in running-order "as had"? Go ahead and run it a while, first.

    It will identify "needs" better, and you can prioritize for more efficient and effective TLC with best and most immediate payback, value-for-time if not also value-for-money as you address those needs.

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    Quote Originally Posted by thermite View Post
    Alemite Zerks are, in fact "legit" for supplying OIL as well as grease. Check with the PO. If he has an oiler fitted to match a Zerk, it might NOT be full of grease.
    Well, the grease oozing out of the front spindle bearing suggests that it might be full of grease.


    Suggestion...
    Brilliant advice. Thank you.


    You may be amazed at how much crud, impacted chips, and even varnish comes off the machine-tool, just as it does yer hands, with the waterless cleaner KEPT "waterless". Also with near-zero add to risking creation of MORE rust in hidden places, and with no damage to paint as is not already perished.
    Got it. I will plan on this. I have time on my side.


    Once you "have full sight" of what's been hidden, I'd stop with the cosmetics, focus on function, do a deeper assessment of what else it needs.

    Paint can wait, and it is USUALLY best that it is MADE to wait.
    You'll be ahead if you put ALL tear-downs on "hold" as well.

    It is intact and in running-order "as had"? Go ahead and run it a while, first.

    It will identify "needs" better, and you can prioritize for more efficient and effective TLC with best and most immediate payback, value-for-time if not also value-for-money as you address those needs.
    I am fully aligned with this approach. Thank you for taking the time put this together. It runs now. I want the grease out and to inspect the spindle bearings to ensure that the grease wasn't added to keep the spindle from knocking around. I know I can't get new boxes for it, but a solution could be found for sure if a problem exists. Otherwise, I'm game to start making chips once I get it home, which will annoyingly be in a few weeks as the PO has a Model-T tore down between the lathe and the door to his shop.


    Cheers!

    -Jake

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    Can anyone explain what the hand wheel on the aft end of the quick change does? Is that a way of manually disengaging the lead screw when using the feed rod only?
    Mine has more or less a knob - exceedingly difficult to turn (likely because it sat outside). It switches from lead screw to feed rod

    Here is a photo

    100_1986.jpg

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    Another view of the quick change:
    g-k-quick-change-1917-1.jpgg-k-quick-change-2.jpg

    William Allen Greaves
    william-greaves-1917.jpg

    Fig. 3 is taken from the vertical plane 3-3 in Fig. 4
    Fig. 2 is the end view (cut-away) view of Fig. 1
    clutch-1921-patent-applied-1.jpgclutch-1921-patent-applied-2.jpg
    Fig. 3 looks like the clutch that was upgraded as shown in post #4
    John

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    Quote Originally Posted by jhruska View Post
    Another view of the quick change:
    John, thank you. All of this old info is gold.

    And J.O. thank you for the gear box info, along with everything else.

    I got the GK home yesterday and spent some time today having a good look over it. I don't have any useful photos, sorry. I will get some tomorrow.

    Random observations:
    • •This is an "early" model and has the old one-sided frictions that are actuated from the quadrant side.
    • •The apron linkage and external control rods for the frictions are missing.
    • •The main lever shifts from forward to reverse just fine without the apron control.
    • •The lowest speed cannot be selected as the selector arm fouls on an internal component of unknown purpose.
    • •The back gear selector works well between high speed, low speed and neutral.
    • •The apron frictions seem in good repair and function as expected.
    • •The lead-screw/feed-rod selector rotates freely between the two options.
    • •The compound slide was frozen. Loosening the gib screw and tapping the compound rest forwards with a brass drift released the tapered gib and freed it up.
    • •The Kirkelie QCTP has 5 different holders and works well enough.
    • •There has so far been no rust. Anywhere.
    • •The back right T-slot in the carriage was broken out and poorly welded in the past. At least all the metal is there.
    • •The quadrant cover fouls on the spindle gear just enough to make a rumble. I'll adjust that.
    • •My fears were confirmed that grease was hiding excessive spindle bearing clearance. We're talking .050" or more 🙁



    So. Plenty of bummer mixed in with some overall fair results. Along with the fair results is that I actually scored the machine for even less than the asking price as the seller was up for some trading for some work on his 84 Cat forklift. Score for me, but fabricating new bronze boxes was something I was NOT hoping to do. Anyone have dimensions on these? I know they are supposedly 2-5/8" by 4-3/4", but beyond that, I suppose I will have to remove them from the casting and pull the critical dimensions. I cannot find a serial number on this thing. Any idea where to look?

    That's all for now!

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    Quote Originally Posted by Jake_G View Post
    I suppose I will have to remove them from the casting and pull the critical dimensions.
    Sound like a plan.

    Play b***dy Hell trying to get the new ones in if yah don't take the worn ones OUT first, regardless, would you not?



    Problem is "first lathe" pretty well shouts ONLY lathe so how to make new ones?

    Fear not. You came to the right place for the odd shade-tree trick. Or even borderline miracles.

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    but beyond that, I suppose I will have to remove them from the casting and pull the critical dimensions. I cannot find a serial number on this thing. Any idea where to look?
    Right end of flat way cross wise and pad on right end of tail stock nearer operator. My 20 Heavy is L420-37 and the 20 heavy I visited in VA is L420-39. None of this goes anywhere as to serial search since the serial book only covers GREAVES starting in 1941. One could speculate the 420 was for April 1920 - except that there are other lot numbers that have nothing to do with such a supposition

    Half shells are very tight fit massive heavy things. (this front one has .500" wall thickness and much more massive flanges each end) Had to make special tooling to yank them out. Would make good economic sense to LINE them rather than replace them - an exercise no doubt involving some very nice tool building

    dcp_1308.jpgdcp_1309.jpg

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    Quote Originally Posted by johnoder View Post
    Would make good economic sense to LINE them rather than replace them - an exercise no doubt involving some very nice tool building
    Agree that. And that TIME is ultimately an "economic" factor as well.

    Unless a SECOND machine-tool - a basic horizontal mill could be as useful as another lathe - is in yer plan, yah may have to "bootstrap" even the stages to get to where yah can make tooling without perishing of old age before yah complete it by hand.

    Good time to do a recce as to what sort of assistance might be handy, locally, such as getting access to already work-worthy machine-tools yah do not need to own.

    Reminder.. so long as all or nearly all the GEARS are sound?

    Spindle bearings, plain, not rolling-element, might not SEEM like it, but are straighforward, low/no "mystery" work, so in a way the "easy part".

    If only because it is more about quality time and careful planning and working than it is money out of pocket for "exotic" (gear-making..) "usually" hired, third-party resources.

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    Quote Originally Posted by thermite View Post
    Problem is "first lathe" pretty well shouts ONLY lathe so how to make new ones?

    Fear not. You came to the right place for the odd shade-tree trick. Or even borderline miracles.
    I have access to all manner of machines and skilled machinists at work if needed. I also picked up a '34 SB model 415 a couple weeks ago with 3 and 4 jaws for a fair price. And I have access to a grizzly (shame, I know!) Milling machine if I need to horribly mangle something instead of making it flat. It's slightly better than using an angle grinder and a bastard file.

    I think.

    Even so, I can use all the shade tree tricks and borderline miracles I can get!


    Quote Originally Posted by johnoder View Post
    Right end of flat way cross wise and pad on right end of tail stock nearer operator.
    Strange. The flat way is completely void of markings. I can find a few cryptic shapes on the tail stock pad, but mostly just the offset graduations and the centerline mark. It's likely buried beneath some paint back there.

    Quote Originally Posted by johnoder
    Half shells are very tight fit massive heavy things... ...Would make good economic sense to LINE them rather than replace them - an exercise no doubt involving some very nice tool building
    Indeed. I'm envisioning opening up a thick wall pipe to match the bore of the casting, clamping the shells in that and then boring them oversize to get everything concentric once again. From there, what's a typical method of lining the half shells? Sleeving the shaft makes perfect sense, but I haven't ever sleeved a half shell. I could see see making a split bushing and turning it true to fit within the half shells and then opening it up to match the spindle journal, but how to keep the liner from spinning? It's got to have an oil hole for the oiler up top, I suppose one could key the upper liner to the half shell with an insert in the oil hole? Two birds, one stone, and all.

    Quote Originally Posted by thermite View Post
    Reminder.. so long as all or nearly all the GEARS are sound?

    Spindle bearings, plain, not rolling-element, might not SEEM like it, but are straighforward, low/no "mystery" work, so in a way the "easy part".

    If only because it is more about quality time and careful planning and working than it is money out of pocket for "exotic" (gear-making..) "usually" hired, third-party resources.
    The gears seem good. The "internal component of unknown purpose" that the selector arm fouls on is the linkage for bringing the low gear dogs into mesh with the primary sliding gearset. The selector arm is supposed to crest over top of the linkage and then cam everything into place as the the main lever nears the low speed notch, but instead the selector arm pings against the linkage and nothing moves. The gear packs themselves slide easily on the shafts, but there is visible end play on the main shaft as the main lever is moved fore and aft. It seems that I am missing an idler gear for reverse looking into the gear case, as the reverse drive gear and the lower gear shaft have a wide open space between them... I guess I won't be running the spindle backwards any time soon.

    I'm pretty unintimidated by the spindle bearings. Cutting them on this lathe would be a joke as it sits now. But after 4 or 5 iterations, I might get it right IF I had a 4 jaw for it... I need to make an adapter for it. The 2-1/4 x 6 spindle threads are not exactly common fare...

    I'm on my phone. My photos are in my phone. PM will not let me manage photos while using a mobile device. I'll post some when I get to one of those clunky things with all of those buttons you click to make words appear on the screen and some sort of small rodent that you use to point and click on things on the screen.

    Y'all stay safe from the craziness.
    Cheers!

    - Jake

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    I'm pretty unintimidated by the spindle bearings
    Similar in concept to the horribly worn out L&S shifter forks that got "lined" on both bore and face. Lots of fooling around and fixture making resulting in "renewed" old stuff

    I'll add photos to this since they seem to be missing over at PB

    * "Shoeing" Shifting Forks

    The area to "locate" on (on the half shells) is the outside - untouched by wear. All the half shells in my 20 Heavy were made round and then cut in half by a slitting saw - fairly thick, like 3/32". Meaning part of any set up will be to determine best shims to put in that cut to make them round again - before cutting on them

    Page 3 here shows some "new" half shells being made for the L&S apron repair

    Set Up To Bore Apron

    ph

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    Quote Originally Posted by johnoder
    All the half shells in my 20 Heavy were made round and then cut in half by a slitting saw - fairly thick, like 3/32". Meaning part of any set up will be to determine best shims to put in that cut to make them round again - before cutting on them
    I knew about the shims but I didn't realize they were integral to making the bushings round again. Surely the castings are not done the same way? Though the caps must be shimmed as well or removing shims would not tighten the clearance. I am intrigued. Does this mean the castings caps must be shimmed before line boring if that is required? This isn't a particularly crazy possibility, but I had always figured the caps were bolted solid and line bored centered on the split line. Good news is that this thing cuts well enough but the surface finish is not gonna win any beauty contests until we get the spindle tightened up.

    Hopefully tomorrow I can upload a couple pictures. I'm getting an unnerving clicking with the reverse clutch engaged that suggests I should stop trying to see what happens when I pull the big lever back, but I do want to understand what the source of the noise is.

    Otherwise, it is perfectly happy making chips.

    Cheers!

    -Jake

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    Quote Originally Posted by Jake_G View Post
    I knew about the shims but I didn't realize they were integral to making the bushings round again. Surely the castings are not done the same way? Though the caps must be shimmed as well or removing shims would not tighten the clearance. I am intrigued. Does this mean the castings caps must be shimmed before line boring if that is required? This isn't a particularly crazy possibility, but I had always figured the caps were bolted solid and line bored centered on the split line.
    "Captain Obvious" generalizing - 'coz this affect things such as building a boring-bar or drill holder for carriage drilling and such easily as much as plain bearings:

    - the bore first, saw later, approach JO outlined WILL require "post" shimming to restore roundness. For clamping or tightening action, of course, yah DON'T (quite) restore it.

    - the split first, CLAMP, (and pin or bolt) first, bore later NO shims, comes out Dead-Nuts round. But you might not always WANT that.

    - the split first, AND shim, then bore, requires the same shimming in-use for the SAME round. But lets you adjust a skosh, either way.

    And then.. there are the situations for clamping or adjusting goals where only ONE side is sawed. Overarms on mills, etc.

    So yah plan ahead. Start with whichever method best serves the later "in-use" goal, any given application. Otherwise one can end up fighting yerself.

    Back to this particular spindle, then:

    - At fifty-thou of slop,

    -- I would FIRST want to sort out whether, and by how much, I had to grind the journal surfaces on the spindle, and what size that took it down to.

    I'd want to avoid the cost and nuisance of hard-chroming for build-back, and the subsequent second grinding operation. I'd even consider taking it FURTHER down, then shrinking a hardened and ground sleeve onto it. Done often enough folks make and sell those goods as a product line.

    -- Even so, presuming I'm at, for example, only 70 or 80 thou undersize, I'd then look to how practical it might be to "tighten up" the existing bearing shells with NO further work to the spindle.

    John mentioned "lining" them.

    Yah also need to look at "back" shimming, relieving at the split, then line-boring the resulting out-of-round back to true at the new undersize to suit the altered spindle diameter.

    They may be too thick and stiff for that to be practical? Or it could work a treat.

    This CAN be "bootstrapped" on the damaged lathe itself with ingenuity, guidance, skill and sweat.

    The reduced spindle journal OD plus shrunk-on shell perhaps the easiest as it CAN be done so the shell OD is an OVER size. The worn bearing shells can then be over-bored a skosh for a cleaned-up match, new metal surfaces all-around, few if any scars or pits left. Those need not be show-stoppers, BTW.

    It all gets easier if another machine-tool is available - or a send-it-out "service" - and made good use of.

    Scouting such available resources - local or not - should be as much a part of your planning as focus on what is to-hand already.

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    I knew about the shims
    IMPORTANT....

    The shims I refer too have nothing what ever to do with the shims used in the machine assy. Those are beween head stock casting and bearing cap casting

    The "shims" I refer to are SOLELY related to the space created by cutting the round bronze bearing into half shells at GK's facility. These are the shims you use in reworking that pair of half shells - and you get to decide on what their best value would be as far as ROUNDNESS (of non worn surfaces of course) in the rework set up

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    Quote Originally Posted by thermite View Post
    "Captain Obvious" generalizing - 'coz this affect things such as building a boring-bar or drill holder for carriage drilling and such easily as much as plain bearings:

    - the bore first, saw later, approach JO outlined WILL require "post" shimming to restore roundness. For clamping or tightening action, of course, yah DON'T (quite) restore it.

    - the split first, CLAMP, (and pin or bolt) first, bore later NO shims, comes out Dead-Nuts round. But you might not always WANT that.

    - the split first, AND shim, then bore, requires the same shimming in-use for the SAME round. But lets you adjust a skosh, either way.
    And then.. there are the situations for clamping or adjusting goals where only ONE side is sawed. Overarms on mills, etc.
    Thanks. That makes sense. The experience I have with this is in attaining the final oil clearances crankshaft main/rod bearings with no access to line bore the block after getting the crank back. What we'd do is match the bearing shells as best we could to get as little variation as possible and then tighten up any loose clearances by lapping the cap and half shell until it fell in line with the rest. Mind you, we only ever took a few tenths off using this approach but it worked a treat. I suppose this is equivalent to only shimming one side, but the shells were always new, so shaft centerline was never moved relative to the block or top of the piston.


    So yah plan ahead. Start with whichever method best serves the later "in-use" goal, any given application. Otherwise one can end up fighting yerself.

    Back to this particular spindle, then:

    - At fifty-thou of slop,

    -- I would FIRST want to sort out whether, and by how much, I had to grind the journal surfaces on the spindle, and what size that took it down to.

    I'd want to avoid the cost and nuisance of hard-chroming for build-back, and the subsequent second grinding operation. I'd even consider taking it FURTHER down, then shrinking a hardened and ground sleeve onto it. Done often enough folks make and sell those goods as a product line.
    I've been a part of shrinking sleeves onto a handful of big shafts in the past for pumps, gearboxes, dispersers/refiners, etc... That's a very doable option.


    -- Even so, presuming I'm at, for example, only 70 or 80 thou undersize, I'd then look to how practical it might be to "tighten up" the existing bearing shells with NO further work to the spindle.
    This would be ideal, but I'm not holding my breath.


    John mentioned "lining" them.

    Yah also need to look at "back" shimming, relieving at the split, then line-boring the resulting out-of-round back to true at the new undersize to suit the altered spindle diameter.

    They may be too thick and stiff for that to be practical? Or it could work a treat.
    The question becomes how far to take it if this approach seems viable. Dropping a 10 thou shim behind each shell will require 20 less shim between the shells, with the caps resting in the same spot as before relative to the head stock casting. If I shimmed the top and bottom shells evenly, this would maintain spindle centerline, as well. The issue is that these shells are very thick and will not like being pressed into a bore that is .020" too small in diameter. To do this right, I would need a stack of shims to create a crescent shaped shim that "lifts" and supports the shell the full "height", whilst tapering down on the sides to allow the shells to seat fully in the split bore. I need some measurements...


    This CAN be "bootstrapped" on the damaged lathe itself with ingenuity, guidance, skill and sweat.

    The reduced spindle journal OD plus shrunk-on shell perhaps the easiest as it CAN be done so the shell OD is an OVER size. The worn bearing shells can then be over-bored a skosh for a cleaned-up match, new metal surfaces all-around, few if any scars or pits left. Those need not be show-stoppers, BTW.

    It all gets easier if another machine-tool is available - or a send-it-out "service" - and made good use of.

    Scouting such available resources - local or not - should be as much a part of your planning as focus on what is to-hand already.
    As mentioned before, I have access to a machine shop to help me get this going, but I prefer to be methodical and see what I can't accomplish on my own before crying to them. If it comes down to getting it fixed now versus dying of old age before I get the home repairs made, I'll choose the former, but I think I owe it to myself and to this old hunk or iron to do the investigative work to determine best path forward and proceed carefully. I'm up for bootstrapping this if need be. The fun is in how to come up with a plan and then execute it, no?


    Quote Originally Posted by johnoder
    IMPORTANT....

    The shims I refer too have nothing what ever to do with the shims used in the machine assy. Those are beween head stock casting and bearing cap casting

    The "shims" I refer to are SOLELY related to the space created by cutting the round bronze bearing into half shells at GK's facility. These are the shims you use in reworking that pair of half shells - and you get to decide on what their best value would be as far as ROUNDNESS (of non worn surfaces of course) in the rework set up
    Hmmm. I need to draw a picture.
    bearing-shells.jpg

    Sorry for being such a pain on this. My brain is slow, but once things FINALLY sink in, they're usually there to stay for quite a while.

    Cheers!

    -Jake

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    Like the first "like this" - shims for assy quite thin

    Gap created by making half shells from round quite large in comparison

    Incidentally...the half shells are not only tight flange to flange -they are also pinned/ doweled (anti-rotation) top and bottom (maybe wrong here, maybe only bottom and "dowel" hole in cap probably oil feed)

    Dowel hole partially visible here (big annular groove GK's idea of lube stop - so not all over outer ends)

    dcp_1298.jpg


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