On 3/14/2012 3:55 PM, Spehro Pefhany wrote:
On Wed, 14 Mar 2012 14:47:02 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Spehro fired this volley in
:

Looking at using some relatively small screws tapped into (probably)
6061 aluminum. Through holes, maybe 0.08" of material. Is it insanity
to think about using a cordless hand drill and run them right through
without backing off (assuming a good quality coated tap and aluminum
cutting fluid)?


Maybe with a 65% thread clearance hole, but I wouldn't. Hell! 0-80 is
small enough to break just by thinking about tilting it off-axis. How
would you get it straight with a hand-held drill?

What's the matter with chucking it up in a finger vise, and doing it that
way? At least, then you could use a drill press to get your initial
alignment.

LLoyd

Mostly to save time, and because I've gotten away with it on larger
taps, but your point is well taken.. much off-axis force is going to
be fatal, and there won't be much 'feel' with a heavy drill.



You could try chucking the tap in a drill press (NO POWER) to get
straight then turning the chuck by hand.