Beginner - Can anyone help me with tool diameter compensation?

[cloudy]

Just completed the X/Y conversion of a manual mill - but now I need to make some parts for the Z axis!

I've designed the part in solidworks, then taken into lazy cam and imported g code into Mach3  - everything looks good with the path. What I don't understand is at what point I tell it the diameter of my endmill - I can obviously oversize the part in solidworks, but i'd rather able to cut right-sized parts...

I see there is a tool setting in mach3 main screen, but what does this do? How do I tell the software whether its cutting the external edge or cutting a hole (ie which way it needs to compensate)

Any help (in beginner terms!) Would be fantastic! Thanks all

James

[BR549]

THe tool comp can be done in many ways YOUR CHOICE. It can be done at the CAD level when you draw them. It can be done at the CAM level 2 ways ,, 1 let the CAM modify the toolpath to account for the tool diam OR 2 let the cam WRITE the tool comp Gcode that the MACHINE will use.

The other is to let the machine DO the tool comp BUT the Gcode HAS to written with that in mind AND you must support the tool table correctly and be assured that the tool and Gcode can ACTUALLY cut the part correctly without guoging the part.

SO what type of Tool comp are you wanting to use???

 Real CNC work is NOT an easy task. It takes a LOT of work and PATIENCE to learn the skills needed to do TOTAL process.

BUT once you learn it is IS a DELITEFULL thing to play with(;-)

Just a thought(;-) TP