Tool Diameter Offsets or Better Method for Making Inlays

Hello All,
              I made a 10mm x 12mm square pocket and a "matching" square cutout/contour. The pocket was more like 9.6 x 11.6 and the cutout more like 10.4 x 12.4. My end mill is 0.8mm. I went through a bunch of fussing with scaling inside of fusion to get the squares just right. Then moved on to a set of donuts with island applying the same scaling. It's a nightmare. Then if i do manage to get it just right I have a bunch more to do (not really but there are other things i'd like to use this technique for). 

So over in the fusion forum a person is telling me to use the tool diameter offsets within linuxcnc. I can not find this anywhere. I've tried changing the tool diameter inside of the tool table, saved, reloaded and absolutely no change in the carve. I figured there wouldn't be but it was worth a shot. The only tool offset I can find anywhere is the length of the tool.

Thank you,
John

Two ways:
1.set the CAM software to do the tool compensation so there is no need to do anything in LinuxCNC
2.set the CAM to export tool offset in gcode and make sure the tools in the tool table on the LinuxCNC side are correct.
Both have ups and downs, but i would use the LinuxCNC side of things, in case i run out of 0.8mm bits i can use 1mm bits and the only thing to change is the entry in the tool table. Otherwise it would require to use the CAM to output gcode compensated for the new 1mm tool.
Disclaimer, i do not have much experience with milling.

So lie to fusion about the diameter sounds good to me and I'm sure i can find more happiness with that than with scaling. Trouble is changing the tool diameter for a single tool several times for two operations in the same setup... Not sure how this would work. I'll head over to fusion and ask. Thanks Tommy.

Best,
John

For more tools you would need to have those same tools also set in CAM and set each of those tools for different operations, again no compensation in CAM, just the tool number and the gcode to activate compensation.
That way LinuxCNC will inform you when it is time to change the tool and wait for a tool change before continuing. If you can repeatably change the tools, that is all there is to it.

So I guess I'm not really clear on how to tell fusion about the offsets or how to tell it to apply them. I cloned my 0.8mm tool. Changed the id from 65 to 67 in fusion. Changed diameter to (tried 0.79, 0.78, 0.75 and 0.65). Generated new tool paths and posted using grbl as usual. I also made the clone and subsequent adjustments in linuxcnc tool table, saved and reloaded every time. Not a single change. My 10mm square with an inside pocket consistently comes out 9.8mm. The only way I've been able to get to 10 is to sketch the square a bit over 10. I have stock to leave set at zero in the pocket operation.

So this seems to have turned from how to properly make an inlay to what is cutter compensation and how is it used. I can tell you right now from 10pm to 2am is not the time for me to be messing with this stuff. Today I'm having slightly better results.

I have posted a pocket operation using emc processor and using in controller compensation. Then over in linuxcnc I load the file, make a change to tool# 65, reload the table and the file and boom i can see a clear change in the path on screen.

I've been reading over the tool compensation documentation, but this stuff only confuses me until some part of it makes sense or i can see it in action. Then i start messing with other bits and making more sense.

I might just cut a perfect 10mm x 12mm pocket yet today.

Thanks again,
John