Absolute and relative

[jorgehrr]

I'm new with machine centers.


I mix both when I program lathes (X,U) (Z,W) with out any G code just input the address.
In machine centers can you do the same or you need the G code?
Also, I see an "A" in one of the programs what axes does this have relation with.

Thank you in advance.

Jorge

[Al_The_Man]

A axis will be rare on a lathe, but the convention is that A rotates around X.
B rotates around Y & C rotates around Z.
A,B,C axis for rotary tables for e.g.
On a lathe, if the spindle is used for a Rotary, then it is C axis.
Al.

[jorgehrr]

Thank you Al,

Here is a couple of blocks where I see the "A". I really do not understand why the "A" is in there.

N4 T1 M6
N6 G0 G90 G54 X0. Y0. A0. S1426 M3
N8 G43 H1 Z1.
N10 Z.1
N12 G1 Z-.3 F6.3

Thank you

Jorge

[Geof]

Originally Posted by jorgehrr Thank you Al, Here is a couple of blocks where I see the "A". I really do not understand why the "A" is in there. N4 T1 M6 N6 G0 G90 G54 X0. Y0. A0. S1426 M3 N8 G43 H1 Z1. N10 Z.1 N12 G1 Z-.3 F6.3 Thank you Jorge

A is the 4th axis on a VMC which would be a rotary table mounted on the machine table with the axis of rotation horizontal and parallel to the X axis.

On a machining center Absolute and Incremental (Relativee) commands are selected by G codes; G91 is Incremental, G90 is Absolute.

[jorgehrr]

Thank you guys for your help.

Jorge