Gantry out of Square


Results 1 to 15 of 15

Thread: Gantry out of Square

  1. #1
    Member
    Join Date
    Jul 2017
    Location
    United States
    Posts
    26
    Downloads
    0
    Uploads
    0

    Default Gantry out of Square

    Folks,

    While trying to drill and tap holes for my e-stop sensors. I discovered something out of sorts. my gantry is out of square by at least 1/4". when against the stop on side, there is a 1/4" if space between the stop and the gantry on the other side. the same is true across the x axis on the other side of the machine. I have take some photo's to show the issues. please note the tray for cables to ensure you are looking at the same side of the gantry.

    Any ideas on how to fix this?

    Similar Threads:
    Attached Thumbnails Attached Thumbnails Gantry out of Square-img_6929-jpg   Gantry out of Square-img_6930-jpg   Gantry out of Square-img_6931-jpg   Gantry out of Square-img_6932-jpg  

    Gantry out of Square-img_6934-jpg   Gantry out of Square-img_6935-jpg  


  2. #2
    Member
    Join Date
    Sep 2017
    Location
    United States
    Posts
    78
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    I had the same issue on ours. Here was the fix, based on past experience with other rack & pinion driven routers:

    NOTE: You will probably have to adjust the limit switches to get it to re-home after doing this procedure

    1. Home the machine.
    2. Loosen the 20 gantry bolts (on our Saturn 2 - not sure how many on the Saturn) to finger tight.
    3. Re-home the machine.
    4. If the gantry still appears out of square, manually pull the gantry into close proximity on the side that's off. This is where you may have to adjust the limit switches.
    5. Jog the gantry around the table 2 - 3 times, then home it again.
    6. Snug the bolts on the Y side.
    7. Re-home the machine.
    8. Snug the rest of the bolts down.

    I was having trouble homing our machine after trying to adjust the limit switches to get it to square. After running this routine it homed right away.



  3. #3

    Default Re: Gantry out of Square

    Quote Originally Posted by micknm View Post
    I had the same issue on ours. Here was the fix, based on past experience with other rack & pinion driven routers:

    NOTE: You will probably have to adjust the limit switches to get it to re-home after doing this procedure

    1. Home the machine.
    2. Loosen the 20 gantry bolts (on our Saturn 2 - not sure how many on the Saturn) to finger tight.
    3. Re-home the machine.
    4. If the gantry still appears out of square, manually pull the gantry into close proximity on the side that's off. This is where you may have to adjust the limit switches.
    5. Jog the gantry around the table 2 - 3 times, then home it again.
    6. Snug the bolts on the Y side.
    7. Re-home the machine.
    8. Snug the rest of the bolts down.

    I was having trouble homing our machine after trying to adjust the limit switches to get it to square. After running this routine it homed right away.
    Mick’s Suggestion is spot on. On yours you should remove the gantry support and loosen the brackets underneath it and the 4 bolts on the bottom. Realign, then tighten the bottom bolts first.

    Fine Line Automation
    www.finelineautomation.com


  4. #4
    Member
    Join Date
    Jul 2017
    Location
    United States
    Posts
    26
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Quote Originally Posted by FineLineAuto View Post
    Mick’s Suggestion is spot on. On yours you should remove the gantry support and loosen the brackets underneath it and the 4 bolts on the bottom. Realign, then tighten the bottom bolts first.

    Ok, please forgive my ignorance. my machine isn't yet up and running. I can't "jog" it quite yet. I wanted to get the emergency stop sensors on there before I worked on the electronics. I ended up taking the bolts out and manually pushing on it to get it back into square. Which is it close, but its hard to tell if its actually square vs just close to square.

    Question, are the sensors used for the emergency stop, the same ones used for homing?

    Also, the homing for the "a" axis is that for the rotary "5th axis"? Why would that be different for homing to the regular position?

    Thank you guys for all the help!

    -Michael



  5. #5
    Member
    Join Date
    Sep 2017
    Location
    United States
    Posts
    78
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    If you get it close to parallel to the X axis travel without the limit/proximity/homing sensors in place that's good enough until you install them. I wouldn't worry about getting it perfect until then. Yes, the X-, Y- and Z+ sensors act as both homing and limit switches. The X+ and Y+ and Z- are limit switches, if your machine has them. The big red button is the emergency stop, or E-stop.

    What controller and electronics are you going to run?



  6. #6
    Member
    Join Date
    Jul 2017
    Location
    United States
    Posts
    26
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    I'm using the plug and NUMA 34 electronics from CNC Router Parts . I am installing the motors and sensors now based nate provided in another post.



  7. #7
    Member
    Join Date
    Sep 2017
    Location
    United States
    Posts
    78
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Mach3 or Mach4 or another controller?



  8. #8
    Member
    Join Date
    Jul 2017
    Location
    United States
    Posts
    26
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Quote Originally Posted by micknm View Post
    Mach3 or Mach4 or another controller?
    Mach 3.


    Sent from my iPhone using Tapatalk



  9. #9
    Registered
    Join Date
    Dec 2005
    Location
    United States
    Posts
    160
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Once you square the gantry mechanically as accurately as you can, in mach3 you will have a y axis motor and a slave motor configured. when you reference home, the y axis and slave motors both move home and each motor will stop independent of each other to your home sensors thus squaring the table. You adjust one sensor to make up your difference. you need to ref home each time you start the machine. since you have a smoothstepper you can adjust the offsets from the sensors in config as well without moving the sensors.

    Last edited by sparkness; 12-28-2017 at 10:49 PM.


  10. #10
    Member
    Join Date
    Jul 2017
    Location
    United States
    Posts
    26
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Quote Originally Posted by sparkness View Post
    once you square the gantry mechanically as accurately as you can. in mach3 you will have a y axis motor and a slave motor configured. when you reference home the y axis both motors will move home and each motor will stop independent of each other to your home switches. you adjust one sensor to make up your difference. you need to ref home each time you start the machine. if you have a smoothstepper you can adjust the offsets from the sensors in config.
    Ok. That’s interesting. I was only going to put a sensor on one side of the gantry thinking it would be square. Perhaps I need to rethink that. I do have a smoothstepper that was included. I need to lean about how to configure them.

    When you refer to offsets, do you mean how far the sensor passed over the block before it triggers? I have noticed that the overlaps are different even after following Nates specs. On some there is barely any overlap (1/16). On others there is about half the sensor (3/8”).

    If it was configurable. I would feel much better about changing it in the software!


    Sent from my iPhone using Tapatalk



  11. #11
    Registered
    Join Date
    Dec 2005
    Location
    United States
    Posts
    160
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Ok, the sensor works like this, you press ref y or ref home in mach3, the axis moves towards the sensor. the sensor triggers ( lights up) , now the table reverses till the light goes out now that axis is zeroed. So for that sensor it will always be that distance from the table (where it senses). So in your case you will have 1 sensor 1/4" sticking out further than the other to square your gantry. Actually you should get the gantry square mechanically first then dial in the sensors a few thousandths. Also. with two steppers moving an axis they need to be in sync.They become in sync with the ref home command , they loose their synchronicity when you power down and back up. They can move a tiny amount. this can be caused by micro stepping. for example the motor is between a full step when when you shut down, now you power up and the motor starts out at a full step thus moving out of position by a few micro steps from when it shut down. here is where you can adjust in smoothstepper homing config

    Attached Thumbnails Attached Thumbnails Gantry out of Square-homing-config-jpg  
    Last edited by sparkness; 12-29-2017 at 10:48 AM.


  12. #12
    Member
    Join Date
    Jul 2017
    Location
    United States
    Posts
    26
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Quote Originally Posted by sparkness View Post
    Ok, the sensor works like this, you press ref y or ref home in mach3, the axis moves towards the sensor. the sensor triggers ( lights up) , now the table reverses till the light goes out now that axis is zeroed. So for that sensor it will always be that distance from the table (where it senses). So in your case you will have 1 sensor 1/4" sticking out further than the other to square your gantry. Actually you should get the gantry square mechanically first then dial in the sensors a few thousandths. Also. with two steppers moving an axis they need to be in sync.They become in sync with the ref home command , they loose their synchronicity when you power down and back up. They can move a tiny amount. this can be caused by micro stepping. for example the motor is between a full step when when you shut down, now you power up and the motor starts out at a full step thus moving out of position by a few micro steps from when it shut down. here is where you can adjust in smoothstepper homing config
    Ok, that gives me something to work from. I will have everything up and running in a day or two, I can give it a try then. for now I cannot connect to the smoothstepper quite yet. I am sure when I can, I will have more questions. Thank you for your help!



  13. #13
    Member
    Join Date
    Apr 2010
    Location
    USA
    Posts
    109
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Not to hijack your thread, but I am having pretty much the same issue. I am however not using Mach 3. There is no provision in my software to create offsets for Y and Y slave ( they are both fed from the same out put to individual drives and then wired in reverse polarity ). Is a framing square going to be my best bet for now?



  14. #14
    Registered
    Join Date
    Dec 2005
    Location
    United States
    Posts
    160
    Downloads
    0
    Uploads
    0

    Default Re: Gantry out of Square

    Quote Originally Posted by Erik F View Post
    Not to hijack your thread, but I am having pretty much the same issue. I am however not using Mach 3. There is no provision in my software to create offsets for Y and Y slave ( they are both fed from the same out put to individual drives and then wired in reverse polarity ). Is a framing square going to be my best bet for now?
    not sure what can be done in this instance other than syncing the motors with a timing belt



  15. #15
    Member ger21's Avatar
    Join Date
    Mar 2003
    Location
    Shelby Township
    Posts
    35538
    Downloads
    1
    Uploads
    0

    Default

    Quote Originally Posted by Erik
    Is a framing square going to be my best bet for now?
    Get it as close as you can then do some test cuts and fine tune from there.

    While auto squaring is helpful, the machine should be perfectly square to start.

    Gerry

    UCCNC 2017 Screenset
    [URL]http://www.thecncwoodworker.com/2017.html[/URL]

    Mach3 2010 Screenset
    [URL]http://www.thecncwoodworker.com/2010.html[/URL]

    JointCAM - CNC Dovetails & Box Joints
    [URL]http://www.g-forcecnc.com/jointcam.html[/URL]

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


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

Gantry out of Square

Gantry out of Square