X Y Z Which axis is which?, + and - direction discussion

[tayloredtech]

After watching an old Masso video and talking to other members I have found there to be a few different ways people set up their CNC axis.
But is one way right/ wrong or does it not matter at all?!
I wanted to see what everyone has learnt through their own experience.

I have put together 4 different images A,B,C and D which show each variation I have found. Comment which way you have your set up and why you did it the way you did.
@masso-support set up from his homing video here has Y as the long axis where back left is set to Y(max) and when driven forward over the axis travels towards 0, this is documented in image [D]
I have the opposite set up. X is my long axis and where back left is X0, Y0 and when driven forward over the axis towards X(max), this is documented in image [A]

Which way have you set up your machine?

-Mitch

 

[jolbas]

There is a right and a wrong when it comes to the relationship between the positive directions of the three axis. If positive X is East and positive Y is North, then positive Z is upwards. But that doesn't mean any of the four examples are wrong as long as Z increases downwards in and [C] and Z increases upwards in [A] and [D].

Right-hand rule - Wikipedia

en.wikipedia.org

We have two machines in the workshop. One [A] and one [D].

 

[masso-support]

As Jolbas says there is a right and wrong way to name your axis and it has to do with where you stand to operate your machine.

Standing in front of your machine where you plan to run it from

the X axis always moves left (X0) to right (X max)

the Y axis always moves front (Y0) to back (Ymax)

the Z axis always moves down (Z-) to up (Z+)

While the machine will still cut if you swap the X & Y around, the final cut will come out 90 degrees to your drawing and what you see in the screen.

If you look in the bottom corner of the screen on masso you will see what way each axis should be.

Option D

Cheers

Peter

Edited to make a little clearer.

 

[tayloredtech]

Quote from MASSO Support on May 4, 2019, 11:49 pm

As Jolbas says there is a right and wrong way to name your axis and it has to do with where you stand to operate your machine.

Standing in front of your machine where you plan to run it from

the X axis always moves left (X0) to right (X max)

the Y axis always moves front (Y0) to back (Ymax)

the Z axis always moves down (Z-) to up (Z+)

While the machine will still cut if you swap the X & Y around, the final cut will come out 90 degrees to your drawing and what you see in the screen.

If you look in the bottom corner of the screen on masso you will see what way each axis should be.

Option D

Cheers

Peter

Edited to make a little clearer.

Thanks @jolbas and Peter @masso-support really helpful information!!
I have found both [D] and are represented many times while looking around online which is what prompted the discussion.

Peter, you are right in that in [A], [C] the work comes out side ways if you are looking straight down the machine which for many months confused me. I can walk around my machine as I use a wireless keyboard and have my large screen above the back end so I think changing the X and Y will be of benefit to my set up.
I find it very unfamiliar though to have a home position not zero at all axis, I'm sure it will make sense after a while but 3 zeros at home made my OCD happy lol!!

@jolbas Do you not get confused with having two machines in a backwards configuration or do you simply use templates for each? What reason do you have them set this way?
Has anyone else had issues with their intial set up?

 

[breezy]

Quote from TayloredTech on May 5, 2019, 1:02 am

I find it very unfamiliar though to have a home position not zero at all axis, I'm sure it will make sense after a while but 3 zeros at home made my OCD happy lol!!

Has anyone else had issues with their intial set up?

I originally setup the 3DTek Heavy Mill with the homing and X0Y0 at the same corner - front left (figure D), but space constraints forced me to move the homing position to the right rear and X0Y0 has moved 200mm away from the physical corner of the machine.

This has worked to our benefit as a G28 at the end of the G-code moves the spindle out of the way for loading and unloading the job.

Regards,

Arie.

 

[jolbas]

@tayloredtech. Both of our machines have X increasing to the right and Y increasing away from where I stand when I operate them.

There is one mill for wood similar to the one in your example images which has X and Y as image [D] and the control is located in the lower left corner of the image. And there is the home made plasma cutter with Masso which is setup like [A] and it's operated from top left corner if referring to your example image.

Your examples doesn't specify a front side so I assumed it wasn't important.

 

[masso-support]

Hi Guy's

Had a bit of time on the weekend and made a short video on identifying your X & Y axis.

Jolbas is exactly right. it all depends on where you stand.

Cheers

Peter

 

[tayloredtech]

Quote from Jolbas on May 5, 2019, 4:58 am

@tayloredtech. Both of our machines have X increasing to the right and Y increasing away from where I stand when I operate them.

There is one mill for wood similar to the one in your example images which has X and Y as image [D] and the control is located in the lower left corner of the image. And there is the home made plasma cutter with Masso which is setup like [A] and it's operated from top left corner if referring to your example image.

Your examples doesn't specify a front side so I assumed it wasn't important.

Thanks Jolbas, Peter and Arie. Sorry for the late reply. I reset my axis and polarity on each axis and instantly found things much more intuative haha. I'm still trying to remember how I got to my original set up as it's not my first machine. But either way, moving the machine around is now much more straight forward. I think this thread and your video Peter will help others not get confused like I was going further!

Mitch

 

[dsherburn]

My CNC Router Parts machine is a 4x8 foot table. I stand in front of the X axis. My X axis is the 4' and the Y is the long (8') axis. X and Y zero is in the front left corner. Y goes positive moving away and X goes positive as it moves to the right. My only issue was that the Y axis uses slaved steppers and I had to upgrade to a 5 axis machine to get the "B" axis (slave to Y) to maintain this orientation. No big deal and it works well.

 

[tayloredtech]

Quote from dsherburn on May 19, 2019, 5:07 pm

My CNC Router Parts machine is a 4x8 foot table. I stand in front of the X axis. My X axis is the 4' and the Y is the long (8') axis. X and Y zero is in the front left corner. Y goes positive moving away and X goes positive as it moves to the right. My only issue was that the Y axis uses slaved steppers and I had to upgrade to a 5 axis machine to get the "B" axis (slave to Y) to maintain this orientation. No big deal and it works well.

With my original machine I just put both Y steppers on the same drive output and inverted one so they both got the same signal.

 

[testyourdesign]

Lol cute little video @masso-support but please keep Peter Junior in your pants. hahahaha

So you say where I stand matters? Its a coordinate naming convention relative to the machine geometry. Once its set it will be the same no matter where you stand!

Cheers, Stephen Brown

 

[dsherburn]

"With my original machine I just put both Y steppers on the same drive output and inverted one so they both got the same signal."



I thought about that, but I have two home switches on the Y axis to "square" the gantry so I was thinking it would help to have a slaved axis.