Homebrew PCBs

Reading this series of posts begs my observations and solution to 
drilling small lot PCBs. I found that the runout on Dremel and its 
clones is too much for good carbide drill bit life. After trying 3 
Dremels I found that all had runout of .010 to .015. Tryed multiple 
collets with no improvement. The problem seemed to be that when the 
unit is off and runout is measured it is near zero, but when turned 
on the run out appears. With an 8 power loupe it can be seen at 
startup. Never took the motors apart but I suspect that one or both 
ends of the armature is rubber mounted as a shock absorber?. 

That being said, I found a cheap single speed drill motor at Jameco 
that has runout of less that .005. It is single speed (20k) and $30. 
It is 1 11/16" Dia. and 4" long straight sided cylinder, greatly 
simplifing mounting in a small drill press. Also the collect shaft 
is about 1 1/2" long to give good field of view at the drill point. 
It is imported and I suspect it has sleave bearings and thus not a 
very long accurate life, but I can live with that given the very low 
runout.

--- In Homebrew_PCBs@yahoogroups.com, "pinoy_nyc@y..." 
<pinoy_nyc@y...> wrote:
>
> Hello, 
>    
>    
>   I just bought the $39.00 craftsman universal drill stand, so I 
can now start drilling PCBs. 
http://www.sears.com/sr/javasr/product.do?
BV_UseBVCookie=Yes&vertical=TOOL&pid=00925923000&subcat=Drill+Doctor+
%26+Drill+Attachments
>    
>   This stand has its own Drill Chuck.
>   Then you can just mount almost any drill to drive the built in 
chuck.
>    
>   I bought this stand since I thought I can use my power 
screwdriver to drive
>   the built in chuck, but I found out that the nose of the 
screwdriver is hex,
> which wont be able to driver the built in chuck, which has a round 
connector,
>   and assume you'll be connecting a drill chuck on top of it.
>    
>   is there some kind of an adaptor (from hex to round) so I can 
use my power screwdriver to drive the built in chuck?...
>    
>   I hope you understand what I'm saying.
>    
>   Thanks.
>    
>    
> 
> 		
> ---------------------------------
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