4 jaw Self centering chuck

4 jaw Self centering chuck

Home › Forums › Beginners questions › 4 jaw Self centering chuck

Viewing 6 posts - 1 through 6 (of 6 total)
  • Author
    Posts
  • #54283
    dixie
    Participant
      @dixie
      Hello. Are 4jaw s/c chucks any better with normal circular material than three jaw s/c chucks. I can see the advantage for turning a round on something perfectly square or drilling through the centre of a square, but are there enough advantages to justify the cost. I ask this question because someone said get your self a four jaw s/c, but could not say why when pressed. 
      #5141
      dixie
      Participant
        @dixie
        #54286
        Bogstandard
        Participant
          @bogstandard
          I use my 4 jaw self centring most of the time, except when using hex bar.
           
          I have found over the years, all my 4 jaw sc chucks have slightly less runout than my standard 3 jaws. usually less than 0.002″.
           
          I find them just a little more versatile for my personal needs as I tend to use round and square stock more than round and hex.
           
          For a first chuck, I would definitely go for a three jaw, then a four jaw a very close second.
           
          Just as a point of interest, no matter which chuck you buy, get a set of soft jaws to fit at the same time. I won’t buy a chuck unless soft jaws are available for it, and if used correctly, soft jaws can make precision machining a piece of cake.
           
          Bogs
           
           
          #54288
          NJH
          Participant
            @njh
            I guess that a 4-jaw s/c will hold round stock a bit more firmly than a 3- jaw and it’s very useful for holding square stock. It won’t however hold hexagon stock which is, perhaps, a more common requirement ( well for me anyway). I managed with a 3-jaw s/c and a 4-jaw independant for many years but recently treated myself to the 4-jaw s/c. Nice but if I could only have one I would go for the 3-jaw.
             
            Norman
            #54289
            Sub Mandrel
            Participant
              @submandrel
              In theory a three-jaw chuck will hold stock firmly with all three jaws, but unless it (and the material) is perfect a four-jaw chuck will only give full contact on three of the four jaws. Just as a three-legged stool will stand without wobbling on a flagstone floor, but you can spend hours ages making a four-legged table wobble free on a flat floor!
               
              In practice I’d guess there is enough give in any decent chuck to mean this isn’t an issue (i.e. you can always nip the jaws up a bit after they make contact). I reckon a badly worn 3-jaw will still grip the work (though it may run out badly) but a badly worn 4-jaw will probably allow the work to wobble.
               
              Neil
               
               
              #54393
              dixie
              Participant
                @dixie
                Hi Many thanks to all those who gave an opinion to my query, I dont think I need to get one just yet.. Thanks Again Brian.
              Viewing 6 posts - 1 through 6 (of 6 total)
              • Please log in to reply to this topic. Registering is free and easy using the links on the menu at the top of this page.

              Latest Replies

              Home › Forums › Beginners questions › Topics

              Viewing 25 topics - 1 through 25 (of 25 total)
              Viewing 25 topics - 1 through 25 (of 25 total)

              View full reply list.