I did a writeup somewhere on her of how I tured a 6mm 1717 motor shaft down to 5mm.
Bacially I clamped the motor in a vise, and then used a drill press with a larger grinding stone (think dremel bit but bigger). I used an esc and radio to spin the motor, then turned on the drill press and manually fed the stone into the shaft.
My reasoning was that the shafts may be hard material, and grinding stone would work better than a file. Plus having everything setup parallel/perpendicular would hopefully produce a better result.
Linc turned down my shaft once And he claims to have turned down a 1717, but other than that
LINCPIMP NEVER TURNS DOWN A SHAFT.
DESPITE STATING OTHERWISE
So what does that say about you Harold? I turned yours down but otherwise never? Yours is that bad huh...
Just for the record I have never seen Harold's shaft, but there is a chance as I have just had an eye test and have a new pair of glasses, so it may be visible now.