problem calling different tool no during G1 feed

Control is Fanuc OTB

I am trying to machine a shallow face groove ,80mm ID 55mm OD with a 2.75mm wide tool ,I have written a prog. that takes the tool to 82mm dia ,chamfers the corner as it plunges to depth then it faces the bottom of the groove, at this point I call another tool no to turn the 55mm diameter on the way out and then take the chamfer off as before.

Code looks something like this.

N110 G0 M13 T0201 X82. Z0.5 S25
N120 G1 G42 Z0.05 F0.1
N130 X80. C-1.
N140 Z-0.3 F0.05
N150 G1 T0203 X55. F0.07
N160 Z0.05 C-0.1
N170 X54.

I have not tried this before and expected it not to run, but it did run , the problem is that as the comp is put on in line N120, the tool moves by double the value of the tool radius(0.1) ie 0.2mm. It does something similar in line N150 I think.

If I set the tool nose rad to 0 it works but of course the chamfer isn't quite right.

As the chamfer is really just to take the burr off I guess I can fudge it by calling for a bigger chamfer but this is now bugging me, any thoughts?

I have tried changing to G41 ,different tool corners +tive tool rad etc all to no avail.