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Grizzly 9x19 G4000 Spindle Bearing

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  • Bruno Mueller
    replied
    Now once again to the delivery edge of my CT 918AM lathe.
    There were no oil nipples on the headstock, nor were there any grease nipples.
    The lubrication holes were closed with screw plugs with a fine thread M10 x 1. I always had to unscrew these screws for lubrication.
    In these threaded holes I screwed in grease nipples for a pressure lubrication press with a suitable thread. Occasionally, a push of grease is given there.
    The nipples protrude over the surface of the headstock. I screwed on a plywood plate of suitable thickness and covered it with a rubber pad.
    For lubrication, I only have to specify the rubber pad and the grease nipple is already freely accessible.

    Leave a comment:


  • wmgeorge
    replied
    Originally posted by darryl View Post
    Since this thread has already fulfilled its purpose, I'll derail it slightly. This oiling or greasing of roller bearings has always made me wonder about the bearings in jet engines. They must be fairly large and run at very high speeds, with high axial and radial loading. To have any lifetime at all, I presume they are cooled, and must have some kind of constant lubricant flow. I can only imagine that they are oil lubed, and that oil cannot build up in the bearing- which means that oil must be able to exit the bearing to be replaced by fresh, and without exceeding a certain fill limit. Anybody have any insight on this?
    PLEASE start your own Thread, every time someone adds to this subject which I have long since lost interest in as its solved I get another Notification!!

    Leave a comment:


  • J Tiers
    replied
    If you look up "agent jayZ" on youtube, he has a video on it. He is an A&P who works on turbines.

    Yes, oil, yes, cooled, insulated, etc.

    Leave a comment:


  • darryl
    replied
    Since this thread has already fulfilled its purpose, I'll derail it slightly. This oiling or greasing of roller bearings has always made me wonder about the bearings in jet engines. They must be fairly large and run at very high speeds, with high axial and radial loading. To have any lifetime at all, I presume they are cooled, and must have some kind of constant lubricant flow. I can only imagine that they are oil lubed, and that oil cannot build up in the bearing- which means that oil must be able to exit the bearing to be replaced by fresh, and without exceeding a certain fill limit. Anybody have any insight on this?

    Leave a comment:


  • Willy
    replied
    Originally posted by Bob La Londe View Post

    I've had CNC mills arrive with oil lines going to fittings mounted in castings that dead end and don't go anywhere.
    That is to say the least, shocking!
    Especially considering that this is not what one would consider a machine aimed at an entry level audience.

    Leave a comment:


  • Willy
    replied
    Originally posted by wmgeorge View Post
    So Willy what should I do, leave the oilers in that have the displaced ball blocking the oil flow or remove and use oilers that work? PS I never said the oil holes were not drilled down to the bearings.
    As I mentioned above, do whatever works best for you. If it works well for your particular use and you are satisfied that the bearings are being lubed adequately then all is good. Nothing at all wrong with oil cups if you're OK with the slight inconvenience of them protruding. I have no problem with ball oilers but will also acknowledge that many do run into the same problems as yourself.
    I just posted here to reassure you that a drop or two of oil occasionally is all that is required. As much as a nice oil bath is more comforting.

    It is neither my machine or shop so do what makes you happy, that is the cornerstone of why we have our own shops right.

    Leave a comment:


  • Bob La Londe
    replied
    Originally posted by wmgeorge View Post
    Who said the oil holes go no where?
    I've had CNC mills arrive with oil lines going to fittings mounted in castings that dead end and don't go anywhere.

    Leave a comment:


  • wmgeorge
    replied
    They are only greased if someone had pulled the shaft and bearings and had done so. Or added grease fittings. Grease for spindle bearings is special type and consistency the wrong type can destroy the bearing. These are factory with oilers and have never been greased.

    I am in the process now of adding lid type cup oilers, not to be confused with the glass jar drip oilers used on hit and miss engines or others.

    Leave a comment:


  • J Tiers
    replied
    Why is there a question if the bearings are actually greased? Grease would be entirely adequate and suitable, and would eliminate the need for oiling.

    At one point it was stated that they were greased (post #5), are they actually not greased but oiled on your machine?

    Leave a comment:


  • wmgeorge
    replied
    So Willy what should I do, leave the oilers in that have the displaced ball blocking the oil flow or remove and use oilers that work? PS I never said the oil holes were not drilled down to the bearings.

    Leave a comment:


  • Willy
    replied
    Originally posted by wmgeorge View Post
    Who said the oil holes go no where?
    Please read post #12.
    If true this would be the pinnacle of stupidity and bad engineering all rolled into one bad example.

    Yes I realize you intend to use oil cups and not drip oilers. The issue I have with the oil cups is that while they are much easier for most to get oil into they do protrude significantly more than a ball oiler, especially in a prominent position like the top of the headstock If this isn't an issue with you then it's not a problem. Personally, right or wrong, I tend to place things there like vernier calipers, tooling etc.
    Either way no biggie if you're okay with that.

    Leave a comment:


  • wmgeorge
    replied
    Who said the oil holes go no where? I can look down inside and see what looks like the back side of a bearing, small view. The issue was the ball oilers was that the ball was jammed down Blocking the oil flow. I removed those and intend to install standard lid type oil cups and oil those bearings once per day while in operation, its not a glass drip oilier. Yes the gaskets are mounted in the HS to keep excess oil from slinging out. I may not be correct about the shielded bearing.
    Last edited by wmgeorge; 03-31-2021, 09:06 AM.

    Leave a comment:


  • Willy
    replied
    One has to wonder if the lube problems on lathes that rely on this method of bearing lubrication is one of perception or reality.
    These types of lathes have been manufactured for decades so I'm guessing the production numbers must surely be in the hundreds of thousands.
    Not that I've been following this issue closely but if these tapered roller bearings were not receiving an adequate amount of lubrication failures would be very prevalent, yet the chorus of owners have been very silent given their numbers.

    As mentioned, this type of bearing requires only a minute amount of lubrication to live a long life. They do not require an oil bath to live a long life. Likely one of the reasons they are used extensively in high power/high rpm two stroke engines that live long lives with as little as 100:1 fuel/oil ratios.

    Ever shake a grease lubed automotive wheel bearing with well over a hundred thousand plus miles on it? They seem apparently dry and they rattle in your hand from lack of apparent lube. The rollers and races appear almost bone dry yet they live a very long life due to an almost microscopic film of oil on them left over from the grease that is essentially just a carrier for the lube oil. Most are good to be put back into service unless the hub has seen water ingestion.

    I find it strange also that your bearings are shielded. Looking at Grizzy's parts list I see that they use a gasket on the outboard ends however the bearings appear to be open. Makes sense to not use a shielded bearing for this application both for cost and functionality.

    As I mentioned I have one lathe a bit larger than this that uses a similar headstock bearing lube system. This lathe is used a lot and after almost 18 years of use the spindle end-play is non existent while runout as measured on the inside of the MT4 taper is just a tick over .0001", maybe .00015", last time I checked early last fall, and all I've ever done was to give each ball oiler 2-3 drops of oil before it's daily use while the spindle is turning.
    So in my case at least the system does work very well without having the added expense of an enclosed system. I'd rather the money was spent somewhere else on a lathe in this price range.

    Nothing at all wrong though with going to oil cups but keep in mind that the oil will run out sooner than later once it gets past the bearing. I see that a lot of folks do have an issue with getting oil into ball oilers but I am blessed with several oil pump cans that have just the right tip size to seal over the ball while not pushing the ball in too far so it has been a non-issue for me. This has also contributed to not being hesitant on oiling when necessary.

    Lots of folks hate ball oilers to the point of this dislike leads to not lubing as required. Although not a personal issue this is my biggest beef with them. Putting them on a machine when they lead nowhere is just plain blasphemy and sacrilegious.

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  • chipmaker4130
    replied
    I know a fellow who removed the oil sight-glass on his china special. It was sealed, had 'permanently perfect' oil level!

    Leave a comment:


  • J Tiers
    replied
    Shielded will retain oil if you can get it in past the shields.

    I think it was here that someone posted about oil ports that simply dead-ended at the OD of the outer race..... NO path for the oil to get into the bearings. Apparently the casting was not changed, it was made for bronze bearings, and just bored larger for ball/roller bearings, which were presumably greased.

    That could result in a nasty surprise for a later owner.

    Leave a comment:

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