Homebrew PCBs

On Tue, 25 Jul 2006 21:53:31 +0200, lcdpublishing  
<lcdpublishing@...m> wrote:

> Yeah, I should keep the broken ones, if for nothing else, to sell
> for scrap value.  I don't have any means of repointing or even
> grinding carbide here.  I do have enough grinders I suppose that I
> could put a soft wheel or a diamond wheel on somthing though.  I
> guess I better start saving them!


When i was at school we made scribe tips out of them broken ones. Still  
have mine somewhere, it will work as a glass cutter ;-)

There were PCB drills with a soft shank where they could cut a thread for  
screw-in tip replacement. But at some point they made them solid carbide.

I keep them all, but have yet to find a good use (lacking a diamond wheel  
too).

However, if you break one by chance with a short section of drill spiral  
remaining they can be used to drill or enlage holes in populated boards  
"freehand" where a normal length drill would break. I wish they'd make  
them with only 2mm or 3mm of thin end. They'd never break! Conrad  
Electronics from germany used to sell spear shaped bits like that, not  
sure if they still do.
It might be possible to grind them shorter, but maybe it is too tricky to  
do by hand (although i'm usually fairly good at drill grinding)

Anyway, with the pivoting drill press i managed to make some quite dull  
before breaking them.

St