Switch Repair - Gonzo Method

User avatar
raoulduke-esq

11 Sep 2021, 17:20

I've not seen this method described before and feel like I've just happened upon it, but if it's old news, please kindly point me toward the original.

I like to buy cheap, so I tend to end up with things that aren't exactly in NIB condition- mainly sold as not working because the boards seem to have a couple dead switches in them. Fixing these was usually a matter of either reflowing solder or replacing the switch plate. This, of course, requires donors. Until now.

These methods were fantastically helpful on a gold badge Omni Key and a Mitsumi M0110A, each of which had a number of dead switches or switches that would only fire sporadically.

After full disassembly, boiling of all plastic, and reassembly some of the Alps were still dodgy- either not firing or only firing sporadically or if the slider had pressure applied at an angle. Something had to be amiss. I disassembled the top housing and tried manually actuating the switch by pressing the actuation leaf with the back of my tweezers. Switch worked just fine, so it has to be a problem with the motion during actuation.

Upon closer inspection, it appeared that the actuation leaf was seated properly but was loose and not quite in its original shape. I took the actuation leaf and pinched the top section together to ensure a firm grip on the top of the switch plate, then bent the legs outward/upwards to ensure they would contact the slider when it was pressed down. This made for a very snug fit on top of the switch plate and aligned the legs so that the slider would contact them when pressed. After reassembly, the switches fired 100%.

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Don't worry that this looks distorted or not quite at the same angles as a functioning switch. Reattaching to the switch plate corrects the top section, and pressing the switch a few times returns the legs more to a normal state. It's possible that you could bend the legs TOO far, in which case the switch would register as pressed even when it's not. Use some bloody discretion here, folks.

Anyway, this got me thinking about the Mitsumi switches from the M0110A. I had about a dozen dead ones before disassembly and about 20 after reassembly that would not register properly with a multimeter continuity check. I had stashed them away in hopes that future me would know what to do, and it seemed that now me had an idea!

I disassembled the bad switches again and tried bending the actuation leaves just as I did with the Alps. That brought a bunch back into action, leaving around a dozen that were just as dead as they had been before cleaning. I should point out that this particular M0110A had been well abused, possibly with a coffee spilled in it at some point. As such, the switch legs were rather corroded. Upon closer inspection of the switch plates, I saw that they were well corroded, too. Manual actuation by pressing the halves together failed, and I noticed there was not much play in the moving part of the switch plate.

Naval Jelly to the rescue. I took those switch plates and submerged them in a puddle of naval jelly and ensured all metal parts were making contact, to include pushing jelly between the plate halves. After 10 minutes I thoroughly rinsed them with water, then with isopropyl, then patted them dry and used canned air to blow out any residual liquid from between the plate halves. Upon reassembly, all of the switches now worked on the multimeter so I put the board together again. After about 3 years of hoping for change I now have a fully functional Mitsumi M0110A.

And thus the Gonzo method (bending actuation leaf; naval jelly if necessary) was discovered.

User avatar
raoulduke-esq

14 Sep 2021, 04:02

VR20X6 has been doing a similar bending for some time using flat tweezers or similar (forceps might work, etc.) on either side of the crease to prevent the metal from bowing by causing it to move only on the existing crease.
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If you've got the tools, try it that way.

VR20X6 says they were likely inspired by Chyros' Alps repair video (https://www.youtube.com/watch?v=1Mhmb2kBuwQ) but I don't think changing the name to "The Inflation Master Method" would have the same ring to it.
Last edited by raoulduke-esq on 21 Sep 2021, 17:59, edited 1 time in total.

User avatar
hellothere

16 Sep 2021, 17:26

I've gotta try this. I have a bunch of Alps switches stashed away because they weren't registering. I wasn't saving them because I was hoping future me would find a possible fix. I was saving them for parts.

User avatar
raoulduke-esq

16 Sep 2021, 18:25

hellothere wrote:
16 Sep 2021, 17:26
I've gotta try this. I have a bunch of Alps switches stashed away because they weren't registering. I wasn't saving them because I was hoping future me would find a possible fix. I was saving them for parts.
Excited to hear if it works for you!

User avatar
hellothere

17 Sep 2021, 00:33

I have one KB, an OmniKey 102, that I'm just finishing up -- loooks like it has only two remaining prooblems, an "O" key that sometimes sticks and a spacebar that's a bit too loud. After that, I'll try this. I might try Evaporust, just because I don't have naval jelly lying around.

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