Need Help! CNC forgot how to follow Accurate diredtions


Results 1 to 8 of 8

Thread: CNC forgot how to follow Accurate diredtions

  1. #1
    Registered
    Join Date
    Jul 2016
    Location
    United States
    Posts
    6
    Downloads
    0
    Uploads
    0

    Angry CNC forgot how to follow Accurate diredtions

    Hello just joined the site! i have got a baffling problem that's not making much sense. so I wrote a program for a bridge mill, Made by Quick mill way back in the 1900's the 60's i beleive. it does use g&m code. however right now I have a program written like such.

    N1 G01 x0.0 y-.3125
    N2 G01 x1.3125 y-.3125
    N3 G01 x1.3125 y.3125

    This is the start of my cutting program and the start of my trouble. I push go for N1 and it's X that moves to .3125 But y remains still. the next move, N2 gets better. X moves to 1.3125 and then y has a sudden epiphany that it should have moved sooner . Playing a wonderful twelve year old assistant that comes into your shop it goes Oh yeah! I need to do this! Off it goes along with X in a diangle motion. past this it only gives me more trouble when i tell X to go to X0.0 again. Both want to go home.

    However If I use whole numbers such as if N1 was written like this G01 x 0.0 y-1.3125. no trouble all is normal with the Quick mill.) could you please get back to me if you have any answer. I suspect that i need to completely reset the parameters of the machine. (not looking forward to it.

    Similar Threads:


  2. #2
    Member awerby's Avatar
    Join Date
    Apr 2004
    Posts
    5728
    Downloads
    0
    Uploads
    0

    Default Re: CNC forgot how to follow Accurate diredtions

    G01 usually needs a feedrate command to go with it, designated by the "F-word" (which doesn't count if delivered orally, as I'm sure you've tried...) You don't need to reissue a command if the position of an axis isn't changed.

    So the program should read more like this:

    N1 G01 x0.0 y-.3125 F20
    N2 G01 x1.3125 F20
    N3 G01 y.3125 F20

    Sometimes the G and F words are modal, so you only have to write them if they change.

    [FONT=Verdana]Andrew Werby[/FONT]
    [URL="http://www.computersculpture.com/"]Website[/URL]


  3. #3
    Member handlewanker's Avatar
    Join Date
    Sep 2006
    Location
    Australia
    Posts
    6463
    Downloads
    0
    Uploads
    0

    Default Re: CNC forgot how to follow Accurate diredtions

    Hi....being a noob too with G code, one thing I did learn from the experts and that is once you write G01 it stays at that until you change it to something else....modal and all that....no need to write it again on any other line until it needs to change to G00 for a rapid move etc.

    BTW........is this G code piece you wrote the entire program test piece? ....that is, without the normal formal G code preamble of % and the program 5 digit number and the G20 or G21 to indicate Metric or Imperial dimensions....also G90 or G91 to indicate absolute or incremental?

    Another thing......always write the N numbering in groups of at least 5......as in N5....N10.....N15.....etc to allow inserting additional lines of code when you want to.

    Also, did you set the Mach 3 configuration to Inch or Metric?

    Lots of questions without knowing what your initial Mach 3 set-up is.
    Ian.



  4. #4
    Registered
    Join Date
    Jul 2016
    Location
    United States
    Posts
    6
    Downloads
    0
    Uploads
    0

    Default Re: CNC forgot how to follow Accurate diredtions

    Quote Originally Posted by handlewanker View Post
    Hi....being a noob too with G code, one thing I did learn from the experts and that is once you write G01 it stays at that until you change it to something else....modal and all that....no need to write it again on any other line until it needs to change to G00 for a rapid move etc.

    BTW........is this G code piece you wrote the entire program test piece? ....that is, without the normal formal G code preamble of % and the program 5 digit number and the G20 or G21 to indicate Metric or Imperial dimensions....also G90 or G91 to indicate absolute or incremental?

    Another thing......always write the N numbering in groups of at least 5......as in N5....N10.....N15.....etc to allow inserting additional lines of code when you want to.

    Also, did you set the Mach 3 configuration to Inch or Metric?

    Lots of questions without knowing what your initial Mach 3 set-up is.
    Ian.
    Ian thanks for your reply how ever i do write my program that way. the g code i put up was simply to help illustrate the problem.



  5. #5
    Registered
    Join Date
    Jul 2016
    Location
    United States
    Posts
    6
    Downloads
    0
    Uploads
    0

    Default Re: CNC forgot how to follow Accurate diredtions

    Quote Originally Posted by awerby View Post
    G01 usually needs a feedrate command to go with it, designated by the "F-word" (which doesn't count if delivered orally, as I'm sure you've tried...) You don't need to reissue a command if the position of an axis isn't changed.

    So the program should read more like this:

    N1 G01 x0.0 y-.3125 F20
    N2 G01 x1.3125 F20
    N3 G01 y.3125 F20

    Sometimes the G and F words are modal, so you only have to write them if they change.
    Awerby thanks for that tip perhaps it will help it behave better. i have seen this done before to ensure the machine does it's job. your right that i have treated it as modal on a regular basis.



  6. #6
    Registered
    Join Date
    Jul 2016
    Location
    United States
    Posts
    6
    Downloads
    0
    Uploads
    0

    Default Re: CNC forgot how to follow Accurate diredtions

    I should make a small point . the program is new. I can run any other program that's preloaded before this day. none have given me any troubles. It's like working in the twilight zone. How ever It's weird that I only have the confusion between X and Y when i try to only Cords that are purely in thousandths. A true whole number starting with one inch gives me no trouble.

    Again though I can use any preexisting program with no problem at all. I have tried clearing the memory to be sure it is not the problem.



  7. #7
    Member awerby's Avatar
    Join Date
    Apr 2004
    Posts
    5728
    Downloads
    0
    Uploads
    0

    Default Re: CNC forgot how to follow Accurate diredtions

    Have you tried writing the coordinates that are only in thousands with a "0" in front? So it would be 0.125 instead of .125 ? Some controls are particular about things like that. Often you use a software tool called a "postprocessor" to fix issues like this and adapt toolpaths to your controller.

    [FONT=Verdana]Andrew Werby[/FONT]
    [URL="http://www.computersculpture.com/"]Website[/URL]


  8. #8
    Registered
    Join Date
    Jul 2016
    Location
    United States
    Posts
    6
    Downloads
    0
    Uploads
    0

    Default Re: CNC forgot how to follow Accurate diredtions

    Hey found the problem. It was a piece of code that wasn't shown previously. the machine is rebelling against a g68 code i was using. considering the part is six feet long it made it easier. now i guess I'm braking out the dials."



Tags for this Thread

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 for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

CNC forgot how to follow Accurate diredtions

CNC forgot how to follow Accurate diredtions