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geekhack Community => Keyboards => Topic started by: Oqsy on Sat, 17 July 2010, 15:00:18

Title: Methods for stopping PCB flex in mx11800/11900 etc.
Post by: Oqsy on Sat, 17 July 2010, 15:00:18
I'm in the middle of doing some mods to my mx11800 and I just though about the steel plate from a Dell QuietKey that I just killed.  If the plate were cut to size to fit behind the pcb and were insulated from any contact with the contacts on the PCB (I'm thinking plasti-dip or something similar), would there be any other unintended effects?  I would love to stiffen this board up and give it a bit of weight, and the would take care of both.  Anyone with experience ridding your mx11X00 boards of PCB flex with other methods?  I remember something about gaffers tape, but I've got search tardation today.
Title: Methods for stopping PCB flex in mx11800/11900 etc.
Post by: Findecanor on Sat, 17 July 2010, 18:12:25
My memory may be worse than yours, but I the only tape that I remember something about is "foam tape". The one that is a mm thick. I think that "craft foam" from a hobby store would work better -- it is practically the same thing as foam tape, but without the sticky glue, and it comes in larger sheets.

The soldered pins are all on the underside of the PCB, and I don't think that it would be a good idea to put pressure on them. I think that some kind of spacers are needed that touch the circuit board in-between the pins. The spacers should be of a hard, insulating material. I am thinking that perhaps wood, like popsicle sticks, would work. Sheet plastic would be better, if you can get hold of some cheap. I have heard about "For Sale" signs being a cheap source of cheap sheet styrene in the US, but I have never seen it as I don't live there.
Title: Methods for stopping PCB flex in mx11800/11900 etc.
Post by: Oqsy on Sat, 17 July 2010, 20:27:27
Ah I found the foam tape thread, finally...  for some reason I remembered ricercar's post "proof of concept" (which he's said way more than he should have on this forum, for the record!) when talking about a pcb cut on an mx11X00 as being in the same thread, and searched that phrase and his name, and boom, there it was... the AT101 Space Saver thread (http://geekhack.org/showpost.php?p=178893&postcount=58).  Strange place to run across info on PCB flex in cherry boards :D  I'm thinking I might use that method instead of messing with the plate.  elbowglue hasn't steered us wrong yet! :D