Skip to Content.
Sympa Menu

machinist - [machinist] Chuck in a chuck

machinist@lists.ibiblio.org

Subject: Machinist

List archive

Chronological Thread  
  • From: Lawrence London <lfljvenaura@gmail.com>
  • To: machinist@lists.ibiblio.org
  • Subject: [machinist] Chuck in a chuck
  • Date: Sat, 22 Feb 2014 00:10:33 -0500

http://www.practicalmachinist.com/vb/general/chuck-chuck-280648/

Thread: Chuck in a chuck

  1. 02-21-2014, 05:13 PM #1
    Long Tom is online now Hot Rolled
    Join Date
    Aug 2011
    Location
    Fiddlefart, Oregon
    Posts
    877

    Default Chuck in a chuck

    Curious to hear pro's and con's of this practice. I've got a short run of copper nubs to make and pulling my 10" chuck off my A1-6 spindle is like.... meh. I have a nice Bison collet chuck on a A1-6 backplate that I made.... I chucked it up to save time. Which made me want to hear what the salty pretzels in the bag think of this.

    What I did:

  2. 02-21-2014, 05:15 PM #2
    tdmidget is offline Titanium
    Join Date
    Aug 2005
    Location
    Tucson AZ
    Posts
    2,815

    Default

    Nothing wrong with it. Have seen it done on CNCs running 4000 rpm.
  3. 02-21-2014, 05:21 PM #3
    Tyrone Shoelaces is offline Titanium
    Send a message via AIM to Tyrone Shoelaces
    Join Date
    Apr 2006
    Location
    england
    Posts
    2,812

    Default

    I've done that with a drill chuck if I needed to hold really small jobs. Regards Tyrone.
  4. 02-21-2014, 05:24 PM #4
    Join Date
    Nov 2007
    Location
    marysville ohio
    Posts
    3,872

    Default

    I have a 10" 4 jaw in a 12" 3 jaw right now.
  5. 02-21-2014, 05:25 PM #5
    Spyderedge's Avatar
    Spyderedge is offline Cast Iron
    Join Date
    Aug 2013
    Location
    NY
    Posts
    403

    Default

    People do that all the time. I use a small drill chuck in a chuck for polishing small parts in my wood lathe.
  6. 02-21-2014, 05:26 PM #6
    wgnrr1's Avatar
    wgnrr1 is offline Hot Rolled
    Join Date
    Feb 2008
    Location
    Spooner, WI
    Posts
    596

    Default

    Been there, done that, didn't buy the t-shirt.

    Josh
  7. 02-21-2014, 05:39 PM #7
    thermite is offline Diamond
    Join Date
    Sep 2011
    Location
    Mid-Atlantic USA, South China
    Posts
    9,253

    Default

    Only flaw I see is the presence of a 3-Jaw as 'master'.

    Were it a 4-Jaw 'master', 3-Jaw or collet 'sub', you'd have far better grip AND the inherent ability to dial-in either low/no TIR, OR a deliberate eccentric if there was a need for a run of such.

    JM2CW .. D1-(n) swaps are easy enough here, but that eccentric capability on a plate-mount 5C or ER-series can be handy.

    Bill
  8. 02-21-2014, 05:44 PM #8
    mach2 is online now Cast Iron
    Join Date
    May 2012
    Location
    Indiana
    Posts
    330

    Default

    I threw a chuck doing that one time. Think on that a little.
  9. 02-21-2014, 05:46 PM #9
    Halcohead is offline Stainless
    Join Date
    Apr 2005
    Location
    Bay Area, Ca
    Posts
    1,179

    Default

    I've done the same as others. Obvious discretion applies. And try when grabbing a chuck with a hollowed out casting on the back (such as many 4-jaws) that you hold over solid material rather than a cored section.

    I've also taken my lathe chuck off the spindle with the work still held, then grabbed the chuck in the dividing head chuck, then returned it to the lathe, so that I didn't have to break a setup on finicky, flimsy parts.

    Quote Originally Posted by thermite View Post
    Only flaw I see is the presence of a 3-Jaw as 'master'.

    Were it a 4-Jaw 'master', 3-Jaw or collet 'sub', you'd have far better grip AND the inherent ability to dial-in either low/no TIR, OR a deliberate eccentric if there was a need for a run of such.

    JM2CW .. D1-(n) swaps are easy enough here, but that eccentric capability on a plate-mount 5C or ER-series can be handy.

    Bill
    Look closely, that 3-jaw is set-tru. He can dial it in if he so chooses.
  10. 02-21-2014, 05:55 PM #10
    maxmartnl's Avatar
    maxmartnl is offline Cast Iron
    Join Date
    Jul 2011
    Location
    NL
    Posts
    260

    Default

    Nothing wrong with that! Both 3-jaw AND 5C chucks are SETTRU/SETRITE... You can make it as accurate as you want it to be. Just mark them to always be able to position them in the 0-TIR position and you'll have a 100% repeatable accuracy.
  11. 02-21-2014, 05:58 PM #11
    thermite is offline Diamond
    Join Date
    Sep 2011
    Location
    Mid-Atlantic USA, South China
    Posts
    9,253

    Default

    Quote Originally Posted by Halcohead View Post
    Look closely, that 3-jaw is set-tru. He can dial it in if he so chooses.
    Not by much. And it is still a scroll-back - much less clamping force to-hand than 4-J independents have to offer.

    That part would bother me more than centering.
  12. 02-21-2014, 06:25 PM #12
    maxmartnl's Avatar
    maxmartnl is offline Cast Iron
    Join Date
    Jul 2011
    Location
    NL
    Posts
    260

    Default doubts

    Maybe you haven't noticed that the 3jaw chuck isn't a cheap one, it's a BISON or a ROEHM as well as the 5c chuck is a BISON. Both could work out fine...
    rite.jpg

    Quote Originally Posted by thermite View Post
    Not by much. And it is still a scroll-back - much less clamping force to-hand than 4-J independents have to offer.
    That part would bother me more than centering.
  13. 02-21-2014, 06:31 PM #13
    Greg Menke is online now Titanium
    Join Date
    Feb 2004
    Location
    Baltimore, MD, USA
    Posts
    3,291

    Default

    I'm doing it tonight- a little import 3 jaw (gift) in my nice 12" Pratt-Burnerd, going to be doing some little stuff in brass...
  14. 02-21-2014, 06:32 PM #14
    Spyderedge's Avatar
    Spyderedge is offline Cast Iron
    Join Date
    Aug 2013
    Location
    NY
    Posts
    403

    Default

    Quote Originally Posted by wgnrr1 View Post
    Been there, done that, didn't buy the t-shirt.

    Josh
    You've worn out that saying.....I're read it 3 times today....
  15. 02-21-2014, 06:36 PM #15
    Long Tom is online now Hot Rolled
    Join Date
    Aug 2011
    Location
    Fiddlefart, Oregon
    Posts
    877

    Default

    Quote Originally Posted by thermite View Post
    Only flaw I see is the presence of a 3-Jaw as 'master'.

    Were it a 4-Jaw 'master', 3-Jaw or collet 'sub', you'd have far better grip AND the inherent ability to dial-in either low/no TIR, OR a deliberate eccentric if there was a need for a run of such.

    JM2CW .. D1-(n) swaps are easy enough here, but that eccentric capability on a plate-mount 5C or ER-series can be handy.

    Bill
    Hey Bill! At least as far as runout, the 10" 3-jaw chuck is a Set-Tru AND that Bison 5c chuck is also set up as a Set-Tru. I did a quick setup and got it running about +\- .001" and called it good. For these parts they could .010" out and it wouldn't matter!

    I hear you about gripping power. At least for the operation I'm doing- on copper no less- it won't matter. I do have a lot of faith in the 10" Bison chuck's grip.

    Anyway- your points are good and I'm not arguing them; just making conversation!
  16. 02-21-2014, 06:49 PM #16
    Long Tom is online now Hot Rolled
    Join Date
    Aug 2011
    Location
    Fiddlefart, Oregon
    Posts
    877

    Default

    As long as we are talking about it- that Bison 5C chuck is really nice. Made in Poland, which I think is no longer a given with Bison. It wasn't cheap. I made a Set-Tru backplate for it that bolts to my A1-6 spindle with really great repeatability. I need to find more work for it- I have a ton of 5C collets that came with my other lathe; I just don't seen to get much small work.

    Although, my Webb spinning at 1800 rpm is a little much <g>. What I REALLY need is a top-shelf toolroom lathe. Anyway. Rambling here. I'm beat. Just finished a $2200 run of parts in 8 days, deburred and marked with part #'s today, packed to survive the Apocolypse and away they will go on the UPS truck shortly. This next thing- the little copper nubs- is for the final touch on a run of beer tap handles I made and has no time pressure. Given that, I should just man up and take that 10" chuck off and mount the 5C chuck properly!
  17. 02-21-2014, 06:50 PM #17
    thermite is offline Diamond
    Join Date
    Sep 2011
    Location
    Mid-Atlantic USA, South China
    Posts
    9,253

    Default

    Quote Originally Posted by maxmartnl View Post
    Maybe you haven't noticed that the 3jaw chuck isn't a cheap one, it's a BISON or a ROEHM as well as the 5c chuck is a BISON. Both could work out fine...
    Click image for larger version. 

Name:	rite.jpg 
Views:	35 
Size:	90.4 KB 
ID:	100263
    Then it IS a 'cheap' one. Just not a 'super-cheap' one.
    And still a scroll-driven, not power-driven wedge, ramp, or balanced-lever (see $chunk et al).

    SCHUNK GmbH & Co. KG Spann- und Greiftechnik

    Mind - when it comes to clamping force, virtue amongst scroll-backs - 3-Jaw or other - is akin to virtue amongst hoors.

    There ain't a great deal to be found there, and even so - once stressed by temptation and cheater-bar, it don't last long, nor repeat forever.

    Anything done with proper respect of its limits CAN work, and for a longish time...but in general, if one has the choice, far better to have the outer chuck working on screws, inner or 'held' one on scroll than the reverse.

    Bill
  18. 02-21-2014, 06:53 PM #18
    alskdjfhg's Avatar
    alskdjfhg is online now Hot Rolled
    Join Date
    Feb 2013
    Location
    Houston TX
    Posts
    859

    Default

    I thought this was a standard on lathes with threaded spindles and big chucks.
  19. 02-21-2014, 07:08 PM #19
    maxmartnl's Avatar
    maxmartnl is offline Cast Iron
    Join Date
    Jul 2011
    Location
    NL
    Posts
    260

    Default

    BISON-BIAL SET-TRU are not CHEAP and are not inaccurate. I've a KLOPFER WEDGE type, a BURNERD GRIPTRU 6-jaw and a few EMCO and FORTE STEEL(SCA comparative) and BANI and REISHAUER 3 and 4-jaws chucks and have been able to compare a few makes. Modern BISON/BIAL chucks are equal to the top notch other chucks. The design doesn't make the difference, the make does and the Polish seem to be able to stand to their sayings. Don't underestimate these guys...
    SCHUNK btw is no better then KLOPFER by my findings, or SMW or KITAGAWA.

    Quote Originally Posted by thermite View Post
    Then it IS a 'cheap' one. Just not a 'super-cheap' one.
    And still a scroll-driven, not power-driven wedge, ramp, or balanced-lever (see $chunk et al).
    SCHUNK GmbH & Co. KG Spann- und Greiftechnik
    Mind - when it comes to clamping force, virtue amongst scroll-backs - 3-Jaw or other - is akin to virtue amongst hoors.
    There ain't a great deal to be found there, and even so - once stressed by temptation and cheater-bar, it don't last long, nor repeat forever.
    Anything done with proper respect of its limits CAN work, and for a longish time...but in general, if one has the choice, far better to have the outer chuck working on screws, inner or 'held' one on scroll than the reverse.Bill
  20. 02-21-2014, 08:00 PM #20
    BobRenz is offline Stainless
    Join Date
    Jun 2012
    Location
    Minnesota, USA
    Posts
    1,460

    Default

    As long as the end result meets your accuracy standards, why not? You won't be able to lean into the cut quite as heavily, though.



  • [machinist] Chuck in a chuck, Lawrence London, 02/22/2014

Archive powered by MHonArc 2.6.24.

Top of Page