old machinist

[farmerq]

I have been out of machining for a long time. I am trying to learn to program a cnc mill I have a cheat sheet for the g codes.
I get confused on my X Y axis. I know Z is up an down, but X & Y has me stumped.

Need help!
farmerq

[dshowalt]

Generally speaking think of X and Y as North and South as you look at a map.
When you spread a map out on the table in front of you.

The X is East and West, as you move East that is the Positive (+) X direction.
As you go West that is the Negative (-) X direction.

The Y is North and South, as you move North that is the Positive Y direction. And South is the Negative Y direction.

[cyclestart]

In a spindle-relative-to the-table-sense dshowalt is right. What's actually moving depends on the type of machine.

Place your right in front of you palm up. Thumb in the hitchhike position. Middle finger in the "one finger salute" position. Index finger pointing away from you. These are your spindle positives for a vertical mill.

[bugzpulverizer]

Shouldn't that be (with left hand) thumb up, index pointing away from you (like a gun), and middle finger to the right. Thumb is Z+, index is Y+, and middle finger is X+.

[cam1]

Wow:
X axis moves from left to right when you are standing in front of the machine. X+ is when the table moves from right to left (the tool appears to be moving to the right therefore positive axis direction)
Y axis moves towards and away from you. Y+ is when the table is moving towards you.
Any Z movement that sinks the tool into the workpiece is Z-.

what's on first?
who's on 2nd?

regards

[cyclestart]

Hey, the left hand thing is more comfortable. LOL
Looks like me and switcher went to the same school for contortionists
Building A CNC Router - A Few Hardware Things To Consider!

Apologies for not linking a pic from the get go.

Y+ is when the table is moving towards you.

Not true for bridge machines. I've never worked with a bridge X but expect they exist.

First base: who
Second base: what

[cam1]

Yup, my mistake with the Y+, easy to understand hard to explain...
Some of this other stuff (who's on first etc) may be over the young guy's heads

regards

First base=what's

[ImanCarrot]

That's handy (!), I'll use that.

What I did was draw a big arrow on the handle wheels that move the axes then draw another arrow to say which way the slides moved then stuck X+ve on it. I done it in Tippex (white paint basicaly) then stuck clear tape over it.

It's dead easy to get mixed up when you're tired.

[bugzpulverizer]

Sorry, after looking at picture I now realize we were all talking about the same thing. I guess I just couldn't picture your way. Hope all this helped original poster.

I don't know = third base?

[cyclestart]

What kind of machine are you looking at farmerq?

cam1's explanation is bang on for what we most commonly think of as a mill.

If you extend the definition of mill to include beasts like Vertical Machining Centers the x +/- Y +/- rules still apply. Everything is relative movement ** Sometimes it's important to keep in mind what moves and what's stationary. When a machine is fully enclosed it's possible to get mesmerized by the spindle and forget the actual machine mechanics. Add in some drowsiness and inexperience and next thing you've driven a fixture into the worklight. Don't ask how I know this

** and this is the point I was trying to make. Unfortunately it was done in a clumsy way. When you get around to asking about offsets I'll try to stay out of it LOL. It would probably read like a Japanenglish machine manual.

[ctate2000]

IMHO forget trying to think about machine movement and just remember to think about the machined surface on a piece of paper. X- left, X+ right, Y- down, Y+ up, Z- towards the paper and Z+ away from the paper.

[Mazaholic]

The machines we have,i always remember.
If you are moving away from machine home..you are moving negative.
Don't know if it's that way with all machines, but all the ones i've worked with it is.
Verticals X is left to right,Y is forward and back,Z is up and down.
Horizontals X is left to right,Y is up and down,Z is forward and back.
Thats standing in front of the machines.