Homebrew PCBs

Some might consider the fixed size an advantage. :) The mechanism is 
inherently simpler, and centering can be much more accurate. I don't find 
the "specialness" at all a handicap. Good carbide bits can be had rather 
inexpensively:

http://store.yahoo.com/drillcity/pcbkit.html

Resharpened bits are just as serviceable, and cost under $1 each.

----- Original Message ----- 
From: "Dave" <wa4qal@...>
> One of the problem with a collet mount is that it only accepts
> certain sizes of bits.  Fortunately, Dremel has a Jacobs style
> chuck that will attach to the business end of a Dremel tool and
> allow precision mounting of very tiny bits.  It's item 4486, near
> the bottom of this page:
>
> http://www.dremel.com/HTML/products/accessories/accessories.pdf