>From: Stefan Trethan <stefan_trethan@...>
>Reply-To: Homebrew_PCBs@yahoogroups.com
>To: homebrew_pcbs@yahoogroups.com
>Subject: Re: [Homebrew_PCBs] Re: Pivoting drill press
>Date: Thu, 19 Jun 2003 11:54:17 +0200
>
>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).
I think a microfiche reader could be adapted. The screen is fine, and the
optics are probably OK. Throw away everything else and base it on those. The
drill has to come up from the underside of the PCB, of course, like the old
Excellon machines. The tricky thing is the mechanical linkage between the
optics and the drill. Does anyone know how Excellon did it?
Leon
--
Leon Heller, G1HSM Tel: +44 1424 423947
Email:
leon_heller@...My web page:
http://www.geocities.com/leon_heller_________________________________________________________________
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