512,740 active members
3,209 visitors online
Register for free
IndustryArena Forum > MetalWorking > General MetalWork Discussion > Manual Threading with Compound vs CNC without Compound
Results 1 to 6 of 6
  1. #1
    Join Date
    Jan 2006

    Manual Threading with Compound vs CNC without Compound

    I have a question on Manual vs CNC single point threading. As I understand it, in manual threading, the
    Compound is set at an angle of 29.5 degrees. As the thread is cut, successive cuts are made by advancing
    the compound, not the cross slide.

    Since the CNC machines, at least the ones I have seen, do not have a compound, the only way to make the
    next cut is to advance the cross slide.

    So, does a CNC machine actually engage the next thread cut at a variable point in relation to the indexed
    point of rotation, thereby replicating the use of a compound?

    I hope this question makes sense. I can see it in my mind. It's just difficult for me to put into words.

  2. #2
    Gold Member
    Join Date
    Feb 2009
    Big battle over the whole 29.5 deg thing. But yes, cnc have infeed patterns. Some replicate the 29.5, some do a zig zag pattern, some feed straight in. Depends on the thread type you want to cut. It's usually a preparatory code in your threading cycle.

  3. #3
    Join Date
    Dec 2004
    I don't know too much about it, but a quick google search revealed that you can use different g codes and sub routines for different styles of cutting threads, some feed in at 29°, but it all depends on what codes are supported by your machine control, and if your using CAM or not.

    Sent from tapatalk

  4. #4
    Join Date
    Jan 2006
    Thanks "underthetire" and "Dylwad." That answers my question.
    Looks like I need to investigate the G and M codes.

    Do you know what the reasoning is behind the 29.5 degrees?

  5. #5
    Community Moderator Al_The_Man's Avatar
    Join Date
    Dec 2003
    I would suggest getting a book such as Peter Smid CNC programming.
    The compound infeed the .5 degree difference avoids rubbing of the tool and excessive tool wear.
    G codes are fairly standard and vary as to type of machine, Mill,Lathe, Plasma, EDM etc, M codes are dependent on the MTB and can vary between the same types of machine.
    CNC, Mechatronics Integration and Custom Machine Design

    “Logic will get you from A to B. Imagination will take you everywhere.”
    Albert E.

  6. #6
    Join Date
    Jan 2006
    Thanks for the info Al. I'll checkout the book.

Similar Threads

  1. Lapping compound?
    By zamazz in forum Benchtop Machines
    Replies: 39
    Last Post: 04-29-2013, 04:34 PM
  2. 1720 XMTC Manual and Compound Slide
    By grahasp in forum Shopmaster/Shoptask
    Replies: 2
    Last Post: 08-07-2010, 06:57 PM
  3. compound infeed for threading
    By g30u0w0 in forum Daewoo/Doosan
    Replies: 6
    Last Post: 02-24-2008, 06:05 PM
  4. what is a compound?
    By diluded000 in forum General MetalWork Discussion
    Replies: 1
    Last Post: 07-31-2007, 04:35 PM
  5. Enco Compound Slide Milling & Compound Drilling Table
    By 7ofclubs in forum DIY CNC Router Table Machines
    Replies: 4
    Last Post: 12-24-2006, 05:43 AM

Posting Permissions

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