Tool diameter / finished cut size issues

[djcregan]

Hi
Just wondered if anyone else had experienced this.

I have a 6mm twin flute straight straight bit which is described as 6mm diameter and when measured, does measure 6mm across the flutes. However when cutting parts with no compensation the parts are smaller, which suggests the tool diameter is larger. I am cutting 12mm hardwood plywood in a single pass.

As an example, a width that should be 100mm ends up at 99mm.

Any Comments would be appreciated

[Adrian]

Have you measure the actual cut in the material? It might be deflection of the bit. Try reversing the cutting direction to see if it changes.