stacey@guug.de (05/11/91)
Subject: PC532 - Drilling Extra Mounting Holes, + PCB Layer Schematics
To: pc532@daver.bungi.com george@wombat.bungi.com
- I'd like to support my PCB more comprehensively, particularly around the
CONN 1 area, as supporting my valuable PC532 on just 6 non optimally placed
pillars (even if standard PC/AT placing) worries me.
- I would like to drill extra support holes in the PCB at some or all of:
the corner near R3, end of CONN 1, end of CONN 2, corner near CONN 11,
between CONN 15 & 16 @ both ends, both ends of U6, end of U13.
- Drilling matching non PC/AT standard holes in my chassis would be work well
worth doing, giving me peace of mind when I lever in & out stiff scsi
connectors &/or ram slices.
- I would prefer to use extra pillars screwed into both PCB & chassis because:
- Glueing pillars on to the PCB would be cludgy, & only good for insertion,
not extraction.
- Self adhesive backing pads are too squashable.
The Problem:
- I don't have artwork for PCB layers, so can't see where internal traces/tracks
run. I guess some of the places I've listed may be impossible to drill.
- Have schematics of PCB internal trace layers been released ?,
perhaps as paper copies, or anon ftp'able gif files etc ) ?.
- If not, perhaps George could list safe (x,y) drilling coordinates ? Thanks.
Julian Stacey (stacey@guug.de)george@wombat.bungi.COM (George Scolaro) (05/11/91)
[In the message entitled "PC532 - Drilling Extra Mounting Holes, + PCB Layer Schematics" on May 10, 22:06, stacey@guug.de writes:] > > The Problem: > - I don't have artwork for PCB layers, so can't see where internal traces/tracks > run. I guess some of the places I've listed may be impossible to drill. > - Have schematics of PCB internal trace layers been released ?, > perhaps as paper copies, or anon ftp'able gif files etc ) ?. > - If not, perhaps George could list safe (x,y) drilling coordinates ? Thanks. The pc532 only has 4 active layers (6 total), the 2 outer ones on each side. Sandwiched in between these are the 2 power planes - one vcc the other gnd. You can see all the active traces since there is nothing in-between the power planes, the traces on the inner layers appear black. PLEASE NOTE THAT WHEN YOU DRILL THROUGH YOU MUST BE CAREFUL NOT TWO SHORT THE PLANES WITH BITS OF COPPER - ALSO, DO NOT USE CONDUCTIVE SCREWS FOR THE SAME REASON. USE PLASTIC OR OTHER NON-CONDUCTIVE MEANS. I personally would not want to drill through the board even being careful to remove all pieces of copper from the drilling exercise - but good luck. best regards, -- George Scolaro george@wombat.bungi.com [37 20 51 N / 122 03 07 W]