Tuning pin drilling?

[Mike Spalding]

Ron Nossaman wrote:
> . Since I started using the 9mm Delignit capped maple multilam 
> composite, I get higher final torque with the 6.8mm second pass than I 
> did with Delignit. The bit mic's the same, so it's not wearing down 
> smaller, otherwise I don't know why that is.
> Ron N
>
There must be something subtle happening right at the cutting edge of 
the drill where tiny variations in sharpening / grinding make noticeable 
differences in hole size, or maybe surface texture inside the hole.  
I've been using a Woodcraft fast spiral brad point 17/64 in delignit.  
The first one I bought gave me 120 in-lb with 1/0 pins.  Thinking I'd 
discovered the holy grail, I went out and bought a half-dozen more 
bits.  They all mic the same (.267) but each gives a different pin 
torque.  Except for that first bit, none have given me a tight enough 
fit on a 1/0 pin.  Is a puzzlement.

Mike