Tool diameter compensation/offset ?

Having just broken my only 3mm diameter mill on a Friday evening before a holiday weekend, my only solution is to use a 6mm to cut round the outside of 10 hardboard hexagons I'm making for my weekend project.
I've written the code for the hexagon, and don't really want to run through the calculations again to position the 6mm cutter further out.

EDIT
Done the maths, as no help appeared, but I'd still be keen to learn, as the pentagons were a bit of a pain.
Truncated icosahedron in the making

I know there is a method of offsetting the tool by its radius, using G41 (?) so this is what I want to add to my code.
On my diy machine I have not set up any tool table in the config, which is where I assume I need to do this.
Is this correct ?

Grateful for any help, spelt out for an old newbie, who's still got EMC2.3.5 on ubuntu 8.04 !

John

If you write your code with no offsets in the future, set up a tool table you could use G41 or G42 for the offsets.
linuxcnc.org/docs/html/gcode/tool_compen...:cutter-compensation

Rick G

Thanks for the link, Rick. exactly what I need to learn, and more besides

Regards
John

There is a bit more info in my G code tutorial...

www.gnipsel.com/linuxcnc/g-code/mill04.html

JT

Thanks John.
On a more general note, do I need to upgrade my 2.3.5 version to make use of G41.1 code ?

John

I'm not sure when G41.1 was added, if it doesn't give you an unknown G code error I assume your good to go.

JT

Thanks John.
When I manage to get back into the workshop, and out of 'labouring duties' in the garden, I'll give it a try.
John