Homebrew PCBs

i would guess the 20k rpm achieved by the small hand tool would be enough.

look here:
http://www.megauk.com/cgi- 
bin/mega/lp.pl?page=http://www.megauk.com/pcb_drilling_machines.php
they sell everything from dremel scrap to versions of the model you are 
discussing.

i have no idea what cnc drilling machines cost but rather than investing 5k 
pound in one of this optical hand
operated machines i would try to get a cnc machine.

i was also wondering how such a viewing device can be built, folowing would 
be needed:
maginifying in the range of 10 or so
screen necessary, no eyepiece.
same picture regardless of viewer position, screen alerady ensures this (no 
simple maginifying glass).


please also have a look at Variodrill High Speed Drilling Machine at the 
url above.
this machine uses a simple magnifier. therefore the target has to be close 
to the pcb.
i have seen this unit once but not tried.


Has anyone a idea how one could build a viewing device his own?

i know there is the option small camera and tv screen. i don't like much.
soe years ago there were "student microscopes" (ya know this cheap plastic 
scrap) which also had a projection assembly which could be used as a 
viewing screen (2" size or so).

i also can imagine using a microfilm viewer, but this unit would be rather 
bulky to mount on a pcb drill.


any ideas are very welcome.

another requirement of the viewing device is that it is not allowed to be 
mirrored image
(like in a microscope). it should be showing the image like it is, so that 
easy use is possible.
has anyone used such a student microscope like this? 
http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=3135524120&category=11737
it has a nice big screen.
but i would need to know if the image is mirroed or not, if i move the pcb 
away from me it would move up on screen.
i think all this "projection scopes" have a similar optical assembly, if 
anyone has used one please write.

regards
st



On Thu, 19 Jun 2003 18:07:10 +1000, Adam Seychell 
<adam_seychell@...> wrote:

> Thanks Tom , that makes it more clear. If its not too much effort, I 
> would like to see a few basic pics of the machine you own. With Nawide 
> machine having belt drive, what RPM did this run at ? I'm curious, what 
> do you think is a "good" RPM for manual drilling  around the 0.6mm - 
> 1.5mm diameter range ?
>
> I know your talking 100k RPM and above for the very large and expensive 
> Excellon CNC production drill machines.
>
> Was it quick to change drill bits on these machines ? My guessing is the 
> spindle would feed far upwards so the collet pops up through the flat 
> panel giving you access to it.
>
> Adam