Tuning pin drilling? followup

[kswafford at gmail.com]

Ron,

A while back you asked if I would try the step drill I am using
(.271 with 1/2" LONG 1/4" diam step) for drilling Delignit blocks,  
omitting
the usual cooling.

I had some time, and fooled around with it...as I expected, uncooled,
in delignit, the bit was cooking...uh...that would be too hot (not  
way cool in
teenage parlance).

In the uncooled condition (and unguided) the torque results were  
erratic, with a
40inch/lb variation.

Cooled guided and timed, I have, in-fact, ditched the 2 step drilling  
in favor
of the the step drill.In my set-up, it's producing very consistent  
holes in full
thickness Delignit,
with a variation of only 5lbs or so throughout the block (with mic'd  
pins).

For general info, I've included a couple photos of the guiding  
rig...a very
simple idea provided by my machinist. It drastically improves the  
accuracy of my
marginal
drill press, when accuracy is important.

Jim I


Photos at:

http://tinyurl.com/3dzkud

https://www.moypiano.com/ptg/files/2007-September/000296.html