Lathe Rigid Tapping
Close
Login to Your Account
Results 1 to 17 of 17
  1. #1
    Join Date
    Aug 2018
    Country
    UNITED STATES
    State/Province
    Iowa
    Posts
    14
    Post Thanks / Like
    Likes (Given)
    2
    Likes (Received)
    1

    Default Lathe Rigid Tapping

    Can anyone recommend a good holder for rigid tapping in a lathe? I am going to do alot more tapping and need to good tool life.

  2. #2
    Join Date
    Jun 2013
    Country
    UNITED STATES
    State/Province
    Oregon
    Posts
    1,553
    Post Thanks / Like
    Likes (Given)
    549
    Likes (Received)
    930

    Default

    What kind of lathe?

  3. #3
    Join Date
    Feb 2014
    Location
    Sunny South West Florida, USA
    Posts
    2,881
    Post Thanks / Like
    Likes (Given)
    10698
    Likes (Received)
    3274

    Default

    Yes. But if you're not gonna give us any information, we can't help.

  4. Likes Mtndew liked this post
  5. #4
    Join Date
    Aug 2018
    Country
    UNITED STATES
    State/Province
    Iowa
    Posts
    14
    Post Thanks / Like
    Likes (Given)
    2
    Likes (Received)
    1

    Default

    Sorry Doosan Lynx 2100LSY

  6. #5
    Join Date
    Jan 2019
    Country
    UNITED STATES
    State/Province
    Missouri
    Posts
    123
    Post Thanks / Like
    Likes (Given)
    32
    Likes (Received)
    19

    Default

    On-center tapping with the lathe spindles? Or driven tool tapping?

  7. #6
    Join Date
    Aug 2008
    Location
    Paso Robles, CA
    Posts
    139
    Post Thanks / Like
    Likes (Given)
    26
    Likes (Received)
    18

    Default

    ER32 collets are an acceptable way to hold a tap.

  8. #7
    Join Date
    Aug 2018
    Country
    UNITED STATES
    State/Province
    Iowa
    Posts
    14
    Post Thanks / Like
    Likes (Given)
    2
    Likes (Received)
    1

    Default

    On center tapping

  9. #8
    Join Date
    Oct 2019
    Country
    UNITED STATES
    State/Province
    North Carolina
    Posts
    11
    Post Thanks / Like
    Likes (Given)
    8
    Likes (Received)
    0

    Default

    I tap 2" 11 1/2 pipe thread in my lathe. Stick the end of the tap in the bored tapered hole. Live center in the end. Crescent wrench on the flats on the tap with the wrench end on the cross slide on a leather welding glove. Lathe in low gear. Lube the heck out of it and go. Bump on and off. Put slight pressure on the tail stock while starting, after a few threads it will feed itself. Continue lubing and bumping on and off. Has worked for me. Good luck.

  10. #9
    Join Date
    Sep 2010
    Location
    Victoria Australia
    Posts
    3,723
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1468

    Default

    Quote Originally Posted by Ifitsmetal View Post
    I tap 2" 11 1/2 pipe thread in my lathe. Stick the end of the tap in the bored tapered hole. Live center in the end. Crescent wrench on the flats on the tap with the wrench end on the cross slide on a leather welding glove. Lathe in low gear. Lube the heck out of it and go. Bump on and off. Put slight pressure on the tail stock while starting, after a few threads it will feed itself. Continue lubing and bumping on and off. Has worked for me. Good luck.
    Hardly a method that will lend itself well to a CNC application.

  11. #10
    Join Date
    Jan 2011
    Location
    SF Bay
    Posts
    372
    Post Thanks / Like
    Likes (Given)
    50
    Likes (Received)
    215

    Default

    Greetings,

    GenSwiss stocks some pretty nice floating tap collets that fit various sizes of ER.
    ( Floating Tapping Collets for CNC Machines - GenSwiss )
    I've used the ER-20 sizes for years with great success.
    I've been told (but don't do it myself) that the best way to use them is to underpitch the thread pitch very slightly (0.03120 instead of 0.03125 for 32 pitch for example) That causes them to expand on the way in, and retract on the way out, to let the tap float its own pitch.
    I didn't know that to start, and got great results with just doing the pitch accurately, so I can't see any reason to change. But I pass along the knowledge anyway.

    FWIW
    Brian

  12. #11
    Join Date
    Feb 2014
    Location
    Sunny South West Florida, USA
    Posts
    2,881
    Post Thanks / Like
    Likes (Given)
    10698
    Likes (Received)
    3274

    Default

    Quote Originally Posted by Alberic View Post
    Greetings,

    GenSwiss stocks some pretty nice floating tap collets that fit various sizes of ER.
    ( Floating Tapping Collets for CNC Machines - GenSwiss )
    I've used the ER-20 sizes for years with great success.
    I've been told (but don't do it myself) that the best way to use them is to underpitch the thread pitch very slightly (0.03120 instead of 0.03125 for 32 pitch for example) That causes them to expand on the way in, and retract on the way out, to let the tap float its own pitch.
    I didn't know that to start, and got great results with just doing the pitch accurately, so I can't see any reason to change. But I pass along the knowledge anyway.

    FWIW
    Brian

    Pretty sure using a floating holder is contraindicated for rigid tapping. At least, on a machine that's in good shape.

  13. #12
    Join Date
    Jan 2019
    Country
    UNITED STATES
    State/Province
    Missouri
    Posts
    123
    Post Thanks / Like
    Likes (Given)
    32
    Likes (Received)
    19

    Default

    Unless that is a very new machine,and something has changed. Most lathes do not "rigid" tap with the lathe spindles. If you want to rigid tap on-center you will have to use an axial driven tool.

    If you must use the lathe spindle you will have to use a tension compression type holder. Just like the good ole days.

  14. #13
    Join Date
    Feb 2003
    Country
    UNITED STATES
    State/Province
    Alabama
    Posts
    520
    Post Thanks / Like
    Likes (Given)
    24
    Likes (Received)
    281

    Default

    I’ve run quite a few jobs tapping on center with the main spindle. No tension/compression holder required. 5yo Doosan Lynx.

  15. #14
    Join Date
    Feb 2004
    Location
    Staten Island NewYork USA
    Posts
    3,762
    Post Thanks / Like
    Likes (Given)
    1106
    Likes (Received)
    1797

    Default

    Quote Originally Posted by GENERALDISARRAY View Post
    Unless that is a very new machine,and something has changed. Most lathes do not "rigid" tap with the lathe spindles. If you want to rigid tap on-center you will have to use an axial driven tool.

    If you must use the lathe spindle you will have to use a tension compression type holder. Just like the good ole days.

    Ummm we've been Rigid Tapping in our CNC lathes since 2000.



    As to holders I use ER-32 Collets.

    I originally purchased some funky Tap holders with square drives that do not slip...kinda need them for bigger taps, say over the 1/2-13 in tougher materials. However under that the ER's are more then fine and its nice if they give some letting you know something is off instead of a crunching noise.

    IF I want more tool life and if alignment is not 100% I will use a Tension/Compression holder like the ones Mari-Tool sells...also ER-32 Collet. Down side is a dull tap may take a hair longer to engage and that screws with your depth some.

  16. #15
    Join Date
    Jan 2014
    Country
    UNITED STATES
    State/Province
    Washington
    Posts
    4,655
    Post Thanks / Like
    Likes (Given)
    845
    Likes (Received)
    2531

    Default

    With many controls, rigid tapping with the main spindle of a lathe has been around for over 25 years. Whether or not the ability is spec'd and implemented though is at the machine builders choice.

  17. #16
    Join Date
    Jan 2007
    Country
    UNITED STATES
    State/Province
    New Jersey
    Posts
    953
    Post Thanks / Like
    Likes (Given)
    464
    Likes (Received)
    470

    Default

    Hello, I work for Doosan. Like almost all other machine makes, you should not need any special collets or holders for rigid tapping. Unless maybe for very large taps. We do all of our rigid tapping with standard ER collets mostly.
    If you need any other help with your machine, contact us here at the New Jersey office. 973-618-2500

    Paul

  18. Likes Ox, DouglasJRizzo liked this post
  19. #17
    Join Date
    Jun 2011
    Country
    UNITED STATES
    State/Province
    New Jersey
    Posts
    877
    Post Thanks / Like
    Likes (Given)
    527
    Likes (Received)
    336

    Default

    For rigid tapping on the Doosan, a standard collet chuck and collet should suffice. Tension/Compression holders really only factor into float tapping.
    Remember that the syntax for tapping is important:

    M5 P11 (main spindle) or P13 for sub, P12 for live tool
    G0 G54 G99 T0303
    X0 Z.25
    G97 S250 M29
    G84 Z-1. F.05
    G80 Z2.
    G28 U0
    etc

    To calculate thread lead "F" value = In IPR mode (G99) - 1/# of threads. In IPM (G98) mode it's Rpm/#of threads.


Tags for this Thread

Bookmarks

Posting Permissions

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