A few keys on my beam springs have started acting wonky

vivalarevolución · 21 May 2016, 18:06

Yea, so a few keys on my beam spring are acting weird. The G and H keys are failing to register, and the Y keys is registering multiple presses. The rest of the keys are acting normal. Any ideas about what is going on here?

seebart · 21 May 2016, 18:16

I can only tell you what I have recently experienced while pulling caps on my 5251, this may not have anything to do with your situation! As you know the metal key stem sits inside the plastic stem shaft that also holds the fly plate at the bottom. Now on my 5251 the goves on the metal key stem were worn down so that the key stem does not mount firmly in the plastic stem. These keycaps can also have more wobble on the cap for the same reason. I am currently going through my options to fix this, I will have to improvise. Thanks to chzel and lot_lizard I know what the problem is. I have also noticed that when the PCB is not screwed to the plate evenly problems with contacts can result.

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vivalarevolución · 21 May 2016, 18:29

How would the wearing down the metal key stem affect the ability of the key to function? Does the metal key stem move, but not push the plastic housing with it?

seebart · 21 May 2016, 18:33

vivalarevolución wrote: How would the wearing down the metal key stem affect the ability of the key to function? Does the metal move, but not push the plastic housing with it?

It should not move at all, it may move and it should not. In your case there must be a problem with the contact from the fly plate to the PCB. Have you ever cleaned the PCB?

Make sure the PCB is screwed tightly and evenly to the bottom of the switches. I have very little experience with the Xwhatsit controller. Possibly you need to re-calibrate.

vivalarevolución · 21 May 2016, 18:39

The PCB could be too tight or too loose. I did take apart of the whole keyboard and cleaned a few parts, including the PCB. I will check the tightness of the internals and see if that makes a difference. What's interesting is how all the dysfunctional keys are in the same general location.

seebart · 21 May 2016, 18:42

Don't tighten it too much though. Evenly across the board.

vivalarevolución · 21 May 2016, 19:28

seebart wrote: Don't tighten it too much though. Evenly across the board.

That could be the issue, I think it is overly tight. I will unscrew everything, and make sure to apply the same amount of pressure or turns with each screw. Hopefully this is a quick fix.

I don't think my metal stems are worn like yours, my beam spring was very lightly used.

seebart · 21 May 2016, 19:35

vivalarevolución wrote: I don't think my metal stems are worn like yours, my beam spring was very lightly used.

A lightly used Beamspring is the kind anyone would want, I have two problematic cases.

Good luck with that.

vivalarevolución · 21 May 2016, 22:12

seebart wrote:
vivalarevolución wrote: I don't think my metal stems are worn like yours, my beam spring was very lightly used.
A lightly used Beamspring is the kind anyone would want, I have two problematic cases. Good luck with that.

Well, lightly used, in the relative sense for a 30 year old item.

vivalarevolución · 25 Jun 2016, 17:13

I finally got to adjusting my beam spring. The backplate was a little loose and some tightening of the middle screws solved any issues I had with the nonresponsive or random keypresses. So just make sure those screws are sufficiently tight on your beam springs! Thankfully, the issue was not anything more serious.