The concentricity of the bearings on the chuck, and the chuck's ability to
center the bit accurately, are in question. I have to agree with Evan that
these are important considerations. Rotary tools with collets -- e.g.:
Dremels, Rotozips, routers, laminate trimmers -- will have less run-out than
a Jacobs chuck. Also, the higher speed is useful for making very small
holes.
All is not lost. The most important attribute is that it can guide a tool,
held somewhat rigidly, in a direction more or less perpendicular to the work
table. Certainly it's possible to drill a PCB even by hand (with some
gnashing and great peril to the bits); guiding one with press is already a
great improvement. If you can find a cheap Dremel, and some way to mount it
to the press, it would be close to an ideal drilling station. Bronze
grounding clamps found in the electrical department of Home Depot etc. are
almost custom made for holding their round-ish shapes.
[BTW: did anyone else catch the recent revival of the Rotozip? :) For future
reference, five years is about the right interval for re-introducing retail
flops. It lacked a usable base in its original incarnation. Adding one drove
its price up to where a real laminate trimmer is a viable alternative. I
suggest waiting a few months, and see if you can find something on overstock
for $30 or so. Its 30k rpm motor and huge cooling fan are what you're
after.]
----- Original Message -----
From: "Evan Dudzik" <evandude@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, November 28, 2005 7:23 AM
Subject: Re: [Homebrew_PCBs] Screw Driver to Drill Chuck Adaptor
> those drill stands also don't tend to have very high precision bearings or
> mechanisms... the amount of wobble or other slop that is acceptable with a
> 1/4" drill bit is a LOT greater than the amount that's acceptable with a
> tiny PCB drill bit...
>
> -Evan
>
> On 11/28/05, Mike Young <mikewhy@...> wrote:
>>
>> Screwdrivers are built for low-speed and high torque, the exact opposite
>> of
>> what's needed for drilling small holes. It might be possible to set up a