Results 1 to 11 of 11
  1. #1
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    633

    Default Overhauling BP J head; what lubrication needed?

    As the header says, I'm after info about lubricating the Bridgeport step-pulley J-head that I'm overhauling for a frankenmill project. I've found a million different downloads of the operators manual- which covers day-to-day lubrication- but I've only got one document on overhaul and that doesn't mention lubrication other than that the housing with the back-gears needs to be packed with grease. I'm specifically thinking of the power-feed gear train, which includes the worm-gear carrier assembly, the bevel gears and especially the little gearbox on the side of the head that houses the cluster gears. I can't see how this will get oil from the outside world once it's all assembled, so wondering if it should also be packed in grease, or what? If any of you fellas have overhauled one of these things or knows the answer to this I'd be grateful. I've emailed the bloke in the US who I've bought my overhaul parts from but no reply yet.

  2. #2
    Join Date
    Jun 2012
    Location
    melbourne
    Posts
    341

    Default

    This is a kondia FV1 mill, so not an exact clone, but the same idea.
    Top left shows how my gearbox looked after possibly 40 years of not being serviced. The grease had reverted to oil and powder. The powder was clumped into hard blocks that looked like broken teeth, had me worried at first.
    Oil is dripped into the head through the fitting at the top of the top left picture.
    Middle top picture shows how the oil goes down into the gearbox, there is a slot on the top bushing that collects oil and you can see in the top right picture how that channels the oil down into the gearbox.
    Centre picture shows how I greased mine on reassembly. These gears don’t move very fast so the grease isn’t going to spin off. I converted my head to use all sealed bearings and kluber isoflex nbu15 grease for the spindle bearings, so I don’t oil mine at all now. I should open up the gearbox occasionally to check but I haven't used the auto quill feed in anger yet so it should still look like this.
    Bottom left picture, all cleaned up ready for reassembling. You see that brown felt washer, that stops dirt going down onto the spindle bearings? Oil should also drip through that to oil bearings in the spindle. it occurred to me later that if you use sealed bearings at the top of the spindle, that would stop oil getting to the real spindle bearings, so you have to use that really expensive grease in the lower spindle bearings if you put sealed bearings at the top. Anyway, I cleaned that felt washer for 15 minutes in paraffin, and couldn’t understand why it wouldn’t come clean. Every other mill I saw pictures of show it as white felt. Mine was brown and wet brown just looks dirty and it started off very dirty. It wasn’t until I gave up and dried it I realised it was meant to be brown.
    The back gear on mine has corrosion and pits in the teeth. Kondia went bust, but clausing Kondia in America bought the rights for the FV1 mill. I could buy a new back gear from them but it was going to be $600. I got a lot of advice from Machtool who is an expert in precision machine commissioning and repair. Phil checked the gear and said the surface was only pitted here and there and advised me to use a moly fortified goo and recommended a grease in a grade NGLI 3 – last picture. The back gear runs really quiet, so its good stuff.
    As he said, these machines were industrial and for the amount of home use they will get, they will last another 40 years no problem.
    HEAD.jpg

  3. #3
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    633

    Default

    Thanks for taking the time to reply and post the photos sossity. From what I've seen, the Kondia FV1 is identical in design to the BP but has built to it's own dimensions such that no parts are interchangeable. I'm sure the lubrication principles are the same. I'll pack the cluster gearbox with grease as well as the back gear housing; I'm installing a Mach Tach to read a hall sensor off the bull gear but from what I've read the grease shouldn't upset that.
    My mill does not have the slot in the bronze bush that you show in your top right photo. The felt screen is the same setup; I have a new one on the way as there are some bronze particles from the worm gear embedded in mine- also getting a new worm gear.
    The worm gear carrier shown in your bottom left photo is the same as the BP. It has those three holes in the top that are located in a recess- this looks to me like oil is supposed to gather in that recess and make it's way down those three holes to the moving parts housed in the cradle; what has me puzzled is that I can't see any way for oil to get to it. The oiler that feeds the spindle bearings drips directly onto the felt screen, which is below the worm gear cradle. There's a steel shaft running directly in the bore of the cradle, surely it must need oil?? Above the cradle there's the bull gear bearings- perhaps oil has to come through these? I've installed new sealed bearings here- maybe this is a mistake and I should remove the seals so oil can drip all the way through; problem with this idea is that I have read that the back gear housing can be run as an oil bath if you don't tilt the head.... So either I'm missing something very obvious or the worm gear assembly is supposed to run dry. My hunch is that I'm missing something obvious.

  4. #4
    Join Date
    Jun 2012
    Location
    melbourne
    Posts
    341

    Default

    I think you are right, the oil should drip down from the bull gear. In mine, there is that oil cup on the rhs of the head, which would drip onto the bull gear.
    2.jpg

    I decided not to use this type of oiling and used all sealed bearings and just grease. I will need to occasionally strip and replace the grease, but remember none of those gears move unless you engage them to move the quill automatically. Its not a feature I've used yet. I just drill by hand, but I can see it would be good for boring. It will be a long time before I need to check the grease. Those gears should move pretty slowly (if you have the spindle on high speed, the autofeed is pretty fast even on its slowest gear, and I'm not sure I would ever use it on such a high speed) If you might use the auto quill for drilling parts all day, then I'd say definitely keep the total loss oiling.

    But if you want to use the original oiling you might need to watch out for sealed stopping the oil reaching all the bearings. The main spindle bearings get oiled from that top oil cup too, unless you use that expensive grease instead. The reason I decided not to use total loss lubrication was there were chips in places you could not imagine them getting into when I stripped mine. The oil just moves them all down and eventually into the spindle bearings. There definitely were bits in my spindle bearings. Its worth making sure that your aprin cover that follows down the quill is in good condition and quite well sealed, so chips can't get in there. Because I have a relatively sealed bearing at the top of the spindle I hope that will help keep my spindle bearing clean.

  5. #5
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    633

    Default

    Yep I have just been fiddling with this thing again, finally had a light bulb come on- the whole power feed system is fed from the top by oil that passes through the bearings- in fitting sealed bearings to the bull gear shaft I have effectively isolated the whole power feed system from any source of lubrication. That little trough in the top of the worm gear cradle is located directly below the bull gear bearings. Oil from the top oil cup drips onto the bull gear right at the teeth, then runs down into the bull gear bearings, drips into that trough and lubricates the three rotating parts in the worm gear cradle and then down into all the gears of the power feed. I will remove the bearings and take the seals out of them; I envisage using the power feed a fair bit. The only part that will not get oil from that top oiler will be the top bearing on the pinion gear shaft- funnily enough, those two bearings were sealed whereas the ones on the bull gear shaft were not. So sealed bearings on the pinion shaft, unsealed on the bull gear shaft.

  6. #6
    Join Date
    Apr 2012
    Location
    Healesville
    Posts
    2,129

    Default

    Maybe not relevent to your lubrication but i thought that i would throw this in for you.

    I am doing a few mods, one of the mods was fitting an elec motor for the feed drive, i am going to use flowable grease for all gears except the spindle spees reduction box that will iso68.

    I drilled and tapped 2 holes in the side of the feed box, 1 for a grease nipple and the other for a level plug.

    More details are in the anayak thread in the project forum.

    Cheers, shed20181105_091831.jpg

    Sent from my SM-G900I using Tapatalk

  7. #7
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    633

    Default

    Very interesting mod there shed, will be interesting to see how it goes. I've got enough to keep me busy just getting the bog-standard J head glued onto the overarm of my U2.

  8. #8
    Join Date
    Apr 2014
    Location
    Perth
    Posts
    134

    Default

    shed
    what is flowable grease
    steve

  9. #9
    Join Date
    Apr 2012
    Location
    Healesville
    Posts
    2,129

    Default

    Quote Originally Posted by shaper07 View Post
    shed
    what is flowable grease
    steve
    Hi steve, it depends who makes it as to what it is called by the looks of it, I bought it from penrite recently.

    https://www.repco.com.au/en/brands/p...dge/p/A9372070

    https://www.penriteoil.com.au/applic...fluid-grease#/

    I am using it because it lubes the bronze bushes better in my opinion, it settles so before starting your machine you can get a fairly good idea of the grease levels with a dipstick or level plug.

    I have been using it on my little centec mill and the mill seems to like it, tho it is a bit like whipper snipping around barkers eggs as you need to learn to keep your mouth shut when starting the spindle when it is warm as it can throw a bit of a rooster tail of oil at times.

    cheers, shed

  10. #10
    Join Date
    Apr 2014
    Location
    Perth
    Posts
    134

    Default

    okay
    thanks shed

  11. #11
    Join Date
    Aug 2015
    Location
    Melbourne, Australia
    Posts
    843

    Default

    Pete, The BP rebuild book recommends superlube telfon grease for those areas (bevel and gears etc). I bought a tub of from QLD for $25. Much *much* cheaper than buying in a little tube and I used about 1/10 of it. I did still use two grease gun tubes of other grease for the bull-gear housing.

    The bevels and left-side gears are (teflon) greased and do not get oil flow from the above.

    The oil cups from above do run down to oil the spindle and some other bits. But ... getting oil to the outside of the quill is really not a thing the way BPs are. Here is what I did: make the tube from the RHS head oil cup (meant for the spindle) drip oil onto the rim of the quill where it meets the housing. It you give enough oil, some of it goes down into the quill .. and thus to the bearings through the felt filter, and some of it seeps around the quill edges to lubricate it in the housing.

    Like this, I get oil down to the spindle bearings and out the small holes in the spindle cap, as well as a nicely lubed quill. All very simple.

    Greg.

Similar Threads

  1. Hercus o mill Vertical mill head lubrication
    By china eyes in forum THE HERCUS AREA
    Replies: 0
    Last Post: 14th Oct 2018, 06:57 AM
  2. Indexing head or dividing head?
    By stevee7270 in forum METALWORK GENERAL
    Replies: 16
    Last Post: 16th May 2016, 03:13 PM
  3. Asian Geared Head Lathes - Spindle Bearing Lubrication
    By rickw72 in forum METALWORK GENERAL
    Replies: 10
    Last Post: 23rd Jun 2015, 10:36 PM
  4. Overhauling a Wohlhaupter UPA-4
    By kwijibo99 in forum METALWORK GENERAL
    Replies: 24
    Last Post: 18th Feb 2015, 11:18 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •