[Biggermens]

i no some of you may think this is a dumb question but what direction is Z- Z+ X- and X+ ????

Thanks

[Geof]

If you are talking about standard metalworking vertical machining centers then machine zero, also known as the machine home position, is as far to the right as possible, as far away from the operator as possible and as high as possible. This is for a machine with the X axis travelling across the position of the operator, the Y axis away from the operator and the Z axis up and down.

With this convention -Z movement is downwards, -X movement is to the left and -Y is toward the operator.

And now for the brain bending part...you have to pretend you are sitting on the table of the machine. Machine movement is defined as motion of the spindle relative to the table but on most VMCs it is the table that moves.

[Biggermens]

Crap i am a idiot i ment for a lathe

[Geof]

Lathe??? Okay. Actually I am competing with you for being an idiot; you did mention only Z and X .

Z as far away from the chuck as possible, normally all the way to right, is machine zero.

X as far away from the spindle centerline as possible is machine zero.

Z- moves tool toward chuck.

X- moves tool toward centerline.

In this case always use the spindle centerline as the reference for X and the spindle nose (chuck) for Z.

[Biggermens]

Thanks a lot man that sure help me now

[joecnc1234]

Geof, What machine are you talking about every machine I've ever seen except for a leadwell homed out to the front left side of machine if your standing in front of it z up all the way.
Joe

[Biggermens]

I have a busy bee lathe i installed motors on and now running mach3 turn

[Geof]

Geof, What machine are you talking about every machine I've ever seen except for a leadwell homed out to the front left side of machine if your standing in front of it z up all the way.
Joe

Which is why I said this; And now for the brain bending part...you have to pretend you are sitting on the table of the machine. Machine movement is defined as motion of the spindle relative to the table but on most VMCs it is the table that moves.

Moving the table to the left and front puts the spindle at the home position, the back right hand corner of the table.

When you look at it this way it does not matter whether you are on a moving table machine or a gantry machine. The home position is with Z up, normally at the tool change level, and above the right rear corner of the work area.

[Eurisko]

Ok class,

now Geof will explain cutter radius compensation...

(chair)

[Geof]

Ok class,

now Geof will explain cutter radius compensation...

(chair)

Are you just being a S.A. or do you really want an explanation?

[Eurisko]

No malice intended, Geof.

I was literally LOL when I read your post, not because of anything you said, but because there are two types of machinists:

Those that view positioning as the movement of the table & saddle,
and those that view it as the movement of the tool.

Almost like the cutter comp direction conundrum.

[Geof]

No malice intended, Geof.

I was literally LOL when I read your post, not because of anything you said, but because there are two types of machinists:

Those that view positioning as the movement of the table & saddle,
and those that view it as the movement of the tool.

Almost like the cutter comp direction conundrum.

Yes some people look at it the correct way, some don't.

And what is the conundrum regarding cutter comp?

[Eurisko]

The cutter comp conundrum:
If a tool (with diameter or radius comp) isn't cutting to size, many operators are confused as to what to do with the cutter compensation.

Add? Subtract? Guess?

Unless you're comfortable with deciphering gcode, there is an easier way to determine it. A friend told me this years ago, and it stuck :

The cutter comp describes the tool, how much the actual tool diameter or radius differs from the programmed diameter or radius.

A 1/2 inch end mill with a +.001 diameter comp = a .501 end mill
A 1/2 inch end mill with a -.001 radius comp = a .498 endmill

The program should generate the correct path for the tool that you are describing.

[joecnc1234]

Geof,
Most people call that the Cartesian coordinate system, I believe your answer stated machine zero not mcs zero which are defiantly not the same position. To lesson the confusion of your post to people who don't understand Cartesian I clearly stated most machines home position in laymans's terms.

[joecnc1234]

The movement of xyz is correct as you stated but most people don't understand it the way you stated it. Thats a good reason for geometry class.