3dprintforums logo


Results 1 to 7 of 7

Thread: 1/4 npt internal thread

  1. #1
    Registered
    Join Date
    Jan 2010
    Location
    england
    Posts
    4
    Downloads
    0
    Uploads
    0

    1/4 npt internal thread

    Hi, I have a 1/2 npt and 1/4 npt internal threads I have to machine (screw cut) on a fanuc lathe, can't tap as in very hard steel. I have a 08 14 NPT insert and 06 18 NPT for the 1/4 thread. Problem is I know it's a 1/16 taper but don't know the start dia or the thread length or what size to bore the taper. Do have a engineers hand book that's only any good for the tapping drill size for both these threads, any help would be great.

    Similar Threads:


  2. #2
    Registered
    Join Date
    Jan 2010
    Location
    england
    Posts
    4
    Downloads
    0
    Uploads
    0
    Also I have step gauges and program in metric using a G76 for the thread



  3. #3
    Registered
    Join Date
    May 2004
    Location
    United States
    Posts
    4519
    Downloads
    0
    Uploads
    0
    Is this what you are looking for?

    Attached Thumbnails Attached Thumbnails -pipe_threads_001-jpg   -pipe_threads_002-jpg  


  4. #4
    Registered
    Join Date
    Jan 2010
    Location
    england
    Posts
    4
    Downloads
    0
    Uploads
    0
    Have seen this chart yes Thanks



  5. #5
    Registered
    Join Date
    May 2004
    Location
    United States
    Posts
    4519
    Downloads
    0
    Uploads
    0
    Is the problem in that you do not know how to read the information off of the charts?



  6. #6
    Registered
    Join Date
    Jan 2010
    Location
    england
    Posts
    4
    Downloads
    0
    Uploads
    0
    Yep found it hard to make sence of the chart, I have the job on the machine and need to crack on in the morning. Was just looking for a quick easy way out to get the figures and complete the job



  7. #7
    Registered
    Join Date
    May 2004
    Location
    United States
    Posts
    4519
    Downloads
    0
    Uploads
    0
    For 1/4-18 - Starting Diameter is 0.49163.

    For 1/2-14 - Starting Diameter is 0.77843.

    Does that help?



Posting Permissions

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


About CNCzone.com

    We are the largest and most active discussion forum from DIY CNC Machines to the Cad/Cam software to run them. The site is 100% free to join and use, so join today!

Follow us on

Facebook Dribbble RSS Feed