Getting ALL the fiddly stand-off washers into place before screwing M/B down
Posted on 2006-06-03
Question is in the title. How do YOU all do this?
Although I've never been told this with any authority, my understanding is that the red fibre washers are intended for the TOP of the motherboard to prevent the large screwhead from shorting a track close to the mounting hole. Any recent motherboard I have seen makes this unnecessary because of the large area of solder around the hole, but I suppose that's the theory and reasoning. I know that some people place the washers UNDER the board so that it it sits between the board and the brass stand-off, and whether they are mistaken or not depends on what is taught in A+ certification, etc, that I've never had.
I'm more concerned with the UNDERside of the board where you can't SEE how close to the tracks the brass stand-off might be sitting. This is especially so with some cheaper cases where the standoff holes on the chassis can be slightly misplaced. Most boards have a small amount of latitude to take account of this, but you just don't know how close to the circuitry the misplaced standoff is if the standoffs are badly placed because you can't see them. I know boards are coated, and shorting is probably unlikely unless something scratches through the lacquer to the track, but I like to be careful just in case I short out someone else's motherboard.
I also find that, with a washer between the board and the top of the standoff, :
(a) I don't have to tighten the screws down much to keep the board secure
(b) I can unscrew them without unscrewing the standoff from the chassis hole as often happens with cheap cases and hard-surface to hard-surface interfaces
(c) I don't seem to get as much vibration being transmitted to the sides of a cheaper case.
I find plastic clip-down stand-offs extremely frustrating when it comes to removing motherboard without the help of an octopus, and I don't like flexing the board too much to nip and release them one at a time. I also don't think they hold the board in place as firmly screws. Buying new plastic screw-in type stand-offs is something I invariably have overlooked, but I've always got a bag of washers and screws at hand. I've tried gluing the washers to the stand-offs first, but then the glue either doesn't stick cardboard to metal or you have to wait for a solvent-based glue to dry or the vapour could dissolve the lacquer on the motherboard..
So here's my question(s):
Do any of you actually use the fibre washers on brass stand-offs before screwing down the motherboard?
Where do you locate them?
If locating them UNDER the board, have you any good ideas for holding them in place while lining up the board holes with the stand-offs?
I'm expecting a mixed response here, and as you'll have gathered from the points, this is neither an urgent issue nor one that requires any really serious troubleshooting :-)