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Hi,

I can't get the tool to display correctly in axis. I added tools to the tool table.
In my program I do a
T1 M6
to select tool 1. That tool has a 6mm diameter. The tool in axis however changes from a cone to... nothing. It just disappears.
The manual says the tool should reflect the correct diameter of the tool selected, what am I doing wrong ? Is there anything I should be looking at ? (config files, etc.)

All help welcome, thanks !

brainwave wrote:
Is it vanishingly thin, or not there at all?

Do you have any XYZ offsets in the tool table? (not that that should matter without the G43).

You _might_ need a G43 to see the tool shape. I just always use M6 T1 G43.

Are you working on a real machine? In a sim you might not notice the tool flying off to the tool-change position. In a real machine, of course, you would.

Yep, you need a G43 to "use the currently loaded tool offset from the tool table". Have you set the diameter in the tool table?

John

I'll have to test that out tomorrow. I do have a G43, but before the tool change. I thought that was something to activate and stays activated for the whole session, so I had
G41
G43
T1 M6

I guess I should instead do
T1 M6 G43 G41

and issue G43 G41 after each tool change ?

brainwave wrote:
G43 is needed any time you change tool. I don't know why you would want to change a tool and not load the relevant offsets, but that is the way it is.

G41, however, is "sticky" and will follow the radius loaded by the G43.
Bear in mind you often will not want G41, I almost never use it. Most CAM pre-processors don't either.

well if I am writing some code by hand, I do not want to have to recalculate all the points if I change cutter. Seems G41 G42 are quite useful.

So, using G41 and G43 in the correct order, I see the trajectory view changed in the axis preview, it now reflects the correct offsets. Tol did not change however, I guess I'll see that when I run the program for real.

You might want to spend some time reading the docs on G40/41/42, G43, T, and M6. Cutter compensation is not an on and off thing, you need a lead in move after issuing a G41/42 and lead out after the G40. It is bad form to mix things like tool change and cutter compensation on the same line and may cause an error if two g codes both use the same option word.

T1 M6 G43
G0 X0 Y0 (preposition move)
G41
G0 X1 (lead in move)
... (cut the part
G40
G0 ... (lead out move

John

Thanks a lot for the tips. I have been reading the section on cutter compensation. Getting ready to cut my first ever part on the CNC mini-mill, exciting.

Some advice then, cut some air first if it goes where you expect it to go then cut material.

John

yes, I plan to do that. I actually got a block of blue machinable wax to test things out.