Announcement

Collapse
No announcement yet.

Proper way to unscrew lathe chuck?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Proper way to unscrew lathe chuck?

    Last night I saw a fellow trying to unscrew a 6" 3-jaw chuck from an older Taiwanese 11" lathe. He had put it in back gear, stuck the key in the chuck and was whacking the chuck key as hard as he could with a big dead blow mallet.

    Having owned that lathe myself for a number of years, I'd always unscrewed the chuck by engaging the back gear, setting the chuck jaws fairly far apart and using a long rectangular bar to loosen it with leverage.

    The guy I got it from used to put a wood block between the chuck jaw and the lathe bed, set it at its lowest speed and flip the switch momentarily into reverse. I never much liked the idea of the chuck spinning off, so I didn't use that method myself

    Suggestions?
    Cheers,

    Frank Ford
    HomeShopTech

  • #2
    Having owned that lathe myself for a number of years, I'd always unscrewed the chuck by engaging the back gear, setting the chuck jaws fairly far apart and using a long rectangular bar to loosen it with leverage.
    That's the way I do it...the other 2 methods scare me

    Comment


    • #3
      I'll first try the chuck key method.
      That usually works...but if it's on tight, I'll use the 2X4 between the jaws.

      Comment


      • #4
        Put it in back gear. Chuck up a piece of delrin bar stock. Use a 1" MT drill bit in the tail stock and drill the Delrin until the motor stalls, then switch to reverse. The chuck will unscrew neatly and be suspended on the drill bit with absolutely no danger of falling on the ways. Remove chuck from the Delrin and put the chuck away. Throw away the drill bit and the Delrin 'cause there is no way you are going to get that bit back out.
        Free software for calculating bolt circles and similar: Click Here

        Comment


        • #5
          Crescent wrench to just one of the jaws point it at my stomach and then bump it hard with my palm and it never fails to pop loose. I then make a game of it by putting the lathe in high speed and then hitting the switch at the same time I run for the door. I've actually made it to the door several times before the chuck comes whizzing past me. This exercise serves to keep me fit and gets me a break away from monotonous task. (and if you're wondering how I got monotonous spelled correctly it's cause I use a spell checker!)
          - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
          Thank you to our families of soldiers, many of whom have given so much more then the rest of us for the Freedom we enjoy.

          It is true, there is nothing free about freedom, don't be so quick to give it away.

          Comment


          • #6
            Block of wood clamped in the jaws and a good whack with a dead blow is what I used to use.
            I just need one more tool,just one!

            Comment


            • #7
              Nearly got the cat!!

              Some years ago I was using the lathe for repetition work and there was a lot of off and on of the DC drive unit. with the controls set very fast. Intending to turn off I accidentally went past off and into reverse, there was a screech of belts following which the chuck unscrewed itself, touched the saddle and disappeared through the open window( My shop was then in the third bedroom of our bungalow). Cat was outside on her rope, fortunately awake and aware and the chuck went one way and she went the other. I retrieved the chuck, calmed cat down with some treats and disabled reverse before the wife realised anything was amiss. So every time I screw the chuck off or on I think of *****!!!!! and everyone around wonders why I smile .Regards David Powell.

              Comment


              • #8
                Take a very important part that you just finished working on for the last two days that needs a very fine pitch external thread turned as the final operation. Set up to thread on the back side, away from the chuck, with the spindle in reverse........

                Comment


                • #9
                  I use wood between the chuck jaws to the lathe bed, and lathe in reverse, low gear (60rpm). Plenty of time to start and stop it. Wacking anything on a EMCO is bad... fiber gears in the main drive...

                  I have an interlock cover on the reverse switch... It would mess up my day for the 25lb chuck to come off at 2500 rpm!

                  Comment


                  • #10
                    I use a strap wrench ,with back gear engaged also i made up wood piece to cover the ways. Soon after i got my lathe i was taking the chuck off and itdropped on my hand before i was ready and finger got in the way, shortly after that i made the wood block and use it all the time.
                    scariest thing to hear " I am from the government and i am here to help"

                    Comment


                    • #11
                      Am I right in thinking that clubbing the chuck key is potentially bad for the chuck? That guy was REALLY hitting it!

                      Because this lathe is in "public use" simple procedures are often forgotten, such as oil on the threads when reinstalling the chuck. It takes a good two or three foot long bar to break it loose with a good size guy leaning hard on it.
                      Cheers,

                      Frank Ford
                      HomeShopTech

                      Comment


                      • #12
                        Lathe chuck removal

                        I use a piece of old broom stick about 2 feet long and stick it threw the opened jaws into the spindle. Make is easier and safer than putting a wooden cover protector on the ways under the chuck. You can unscrew the chuck and the broom stick will hold it so it don't drop and / or mash your fingers, plus the broomstick makes handeling the chuck easier too. The stick will be threw the chuck and you can slid it out of the spindle and get a hand on each side of the chuck.

                        Dutchw

                        Comment


                        • #13
                          Threaded Chuck removal

                          Chuck up a piece of 1" pipe that extends into headstock and has 8" sticking out. Apply a 24" pipe wrench near the chuck face pull with left hand and apply hammer smartly to the pipe wrench with the right hand. This gives something to hold onto and keeps from falling on the ways. A large nut welded to the end of a rod chucked similarly. 3/4 Impact applied to nut can work without getting the gear train involved.
                          Byron Boucher
                          Burnet, TX

                          Comment


                          • #14
                            Use of the chuck key, in conjunction with a heavy hammer is definitely not the way to remove a chuck under any circumstances. Even using the key just to remove a snug chuck should be avoided. The pinion and key have a specific purpose, chuck removal is not it.

                            Several of my chucks have a void between the chuck body and backplate. Chips get hung up in there and fall out when installing a chuck, fouling the threads and requiring removal and cleaning a couple of times when installing a chuck. I have filled the gap with RTV to seal it. It has enough flex to permit adjusting the Set Tru chucks yet eliminates the void and makes installation simpler.
                            Jim H.

                            Comment


                            • #15
                              My 9" S.B. has a couple of teeth on the backgears missing because of locking it with the backgears and putting a cresent wrench on a jaw and whacking it with just the palm of my hand. I figured I was safe doing that, after all, it wasn't like I was hitting it hard like with a hammer or anything....
                              Location: Saskatoon, Saskatchewan, Canada

                              Comment

                              Working...
                              X