Smithy CNC Mills User Manual

Page 75

the Y offset and so on for all six axes. There are numbered sets like this for

each of the fixture offsets.

Each of the graphical interfaces has a way to set values for these offsets. You

can also set these values by editing the VAR file itself and then issuing a [reset]

so that the EMC reads the new values. For our example let's directly edit the file

so that G55 takes on the following values.

5241 2.000000

5242 1.000000

5243 -2.000000

5244 0.000000

5245 0.000000

5246 0.000000

You should read this as moving the zero positions of G55 to X = 2 units, Y= 1

unit, and Z = -2 units away from the absolute zero position.

Once there are values assigned, a call to G55 in a program block would shift the

zero reference by the values stored. The following line would then move each

axis to the new zero position. Unlike G53, G54 through G59.3 are modal

comands. They will act on all blocks of code after one of them has been set.

The program that might be run using figure [fig:offsets] would require only a

single coordinate reference for each of the locations and all of the work to be

done there. The following code is offered as an example of making a

squareusing the G55 offsets that we set above.

G55 G0 x0 y0 z0

g1 f2 z-0.2000

SmithyCNC Programmer’s Reference Manual: Coordinate System

8-4