J-head fine feed disassembly help
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  1. #1
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    Default J-head fine feed disassembly help

    I am trying to do a basic external teardown on my J-head so I can splash on a bit of paint to match the rest of the machine. In a nutshell, not trying to do unnecessary work as the machine works fine and is quiet as-is. As you hopefully can see in the pics, Ive got it mostly apart. Unfortunately, Im a bit stuck with removing the handwheel clutch (113). Both the setscrew (6) and the screw and spring (116 & 174) opposite were easily removed but the 3/16" ball bearing (173) refuses to come out. Am I wrong to think the ball bearing should simply fall out without the screw and spring holding it in, thus allowing the handwheel clutch (113) to simply pull off?

    Any/all help is greatly appreciated!

    http://www.truetex.com/bridgeport-manual.pdf




  2. #2
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    It should come off.. Ball will come out eventually...

    There is a key and keyway that can bind it up.

    If it is too tough, drill and tap 2 holes in outer face of collar..

    Make a slide hammer adapter to pull it off.. I would put the trip housing casting screws back in, so you are not pulling on worm...

    Don't press on inner (feed direction) shaft, you will damage the dog clutch pin...

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    Many thanks as always. Any suggestions to help force the ball bearing out? Ive tried spraying WD in there as well as pushing/tapping on it with picks and even a finishing nail but nothing seems to want to move it, even when wiggling the feed reverse shaft in/out. Im hopeful the collar/handwheel clutch should come off easy as it moves up/down a tiny bit fairly easy, unfortunately it appears to be catching on the ball itself.

    When I bought it, the machine had a cobbled handwheel in place of the stock one, but also had a stock one in the base. Also not sure if any of the feed parts were shop made or not, or if the ball bearing is the correct size, you can see in the pics a bit of the scoring and poor surface finish on the shaft the handwheel rides on.

  4. #4
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    I just went into shop and pulled mine out..

    My detent ball drops right out..

    In your case what you can try..

    While rotating the entire shaft assy, push and pull on center (feed direction) shaft.

    This allows dog clutch to engage.. Which should allow ball to be pushed up and out.

    Also try some oil, and high pressure air down the hole (wear eye protection)

    Try pushing down on the ball also while rotating, once you start to get the ball moving....

    Air aimed down the inner shaft length might help too.. Keep rotating and moving inner shaft back and forth..

    If this all fails, removing feed drive worm cradle up top, feed gears, and bevel drive gear (plenty of setscrews..) that sticks down into the 2 (FWD/RVS) bevel gears, will allow whole unit to come out front. Basically a whole head dissasemble job..

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    Ok, Ive given up on trying to get the ball bearing out as all manner of picks, oiling, and 125 psi refused to budge it, so Im trying to remove everything connected to the hand feed assembly in hopes of removing it all.

    I got the worm cradle/input shaft out without issue, followed by the sliding gear assembly/cluster gear shaft next to it. Im a bit confused now tho as the feed drive gear is still in place. I removed the C-clip but it doesnt want to slide out, I suspect bc its still meshed with the feed worm gear. How can I disengage the two in order to slide out the entire handwheel clutch/shaft/ball bearing etc?

    Sorry I cant post pics tonight bc photobucket's down for maintenance. Will post a few tomorrow if necessary. Thanks again!

  6. #6
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    Confused by your description.. The feed bevel gear runs vertically down into the area where the fwd/rvs bevel gears are.

    This gear runs in a bronze bushing which can be a bit tight. I believe there is a setscrew also.. The bushing must come up with the gear..

    Until it is lifted up, the FWD/RVS gears and shaft will not come out the front of head...

    Of course I thought of another way to get the ball out...

    Drill through the inner shaft from other side, and punch it out... The collar has a hole already on other side. The inner shaft would need to be replaced... simple part see below

    Make a bushing so you do not damage the collar hole threads with the drill bit...



    If you are brave and have a TIG welder, you might be able to stick tungsten to the ball to pull it out...

    You will be drilling through the key in the keyway, but that will not hurt anything... Except the 15 cent key...

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    Many many many thanks! The pic was exactly what I needed, I was mistaking the position of the bevel gear and the worm gear. I used a bit more force and got the bevel gear and bushing out, then the whole feed assembly came right out the front, mission accomplished.

    Cant thank you enough for the help. Im always a bit tentative at forcing machine parts together/apart or doing any prying/hammering as Ive seen too many damaged/cobbled machines but sometimes old oil and sticktion need a lil persuasion. Thanks again!

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    Go to E Bay and track down the book "A guide to renovating the Bridgeport 1J milling machine". I see it's up to $ 29 right now. It does a darn good job of showing how to tear one apart and how to reassemble it. Here's the E-Bay web data:

    Rebuild Manual for 1HP Bridgeport "J Head" Mill | eBay

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    Quote Originally Posted by CWB View Post
    Many many many thanks! The pic was exactly what I needed, I was mistaking the position of the bevel gear and the worm gear. I used a bit more force and got the bevel gear and bushing out, then the whole feed assembly came right out the front, mission accomplished.

    Cant thank you enough for the help. Im always a bit tentative at forcing machine parts together/apart or doing any prying/hammering as Ive seen too many damaged/cobbled machines but sometimes old oil and sticktion need a lil persuasion. Thanks again!

    I have the same exact problem, except I cant get the darn bushing and pinion/bevel gear gear out. I removed the circlip thinking i could use the machined groove to aid in removal but no luck.


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