SPDT Switches - Do you keep the washers? What is the correct way to install them?

[FuzzyLotus]

So. I'm currently building yet another Pedal with 4 SPDT toggle Switches.
I usually remove the notched washer, then put the first nut, then put the spdt through the hole in the pedal, then put the "teethed" washer, then the last nut, is that how you should do it? I've always assumed this was the way to do it but never bother to ask around. What is the purpose of the notched washer ? Cheers!

 

[Nostradoomus]

the lock (teethed) washer goes on the inside against the enclosure. So first nut, lock washer (teeth facing enclosure) ---> enclosure ---->notched washer ----> nut

the notched washer is supposed to have an extra hole drilled in the enclosure that the tab sits in to stop it from spinning if it's panel mounted, like the tab on pots, we don't need them for our purposes.

 

[Erik S]

No washers for me thanks.

 

[GAStan]

What @Nostradoomus said but I break the bent tab off and use the notched washer under the outside nut.

 

[lowpitch]

I used to snip off the alignment tab and file it so it looks like a regular washer. I'm lazy though, so now I just do what everyone does and flip it around:

I got some tab-less mini switch washers a while ago but I kind of like the look of the little tab.

 

[Bricksnbeatles]

As far as the washer tab, I just get tabless washers from LMS or McMaster

 

[kristopher]

I snap off the tab. And file a little bit. And use the washer if I screw up drilling the hole.
…so they end up on most builds with switches.

 

[owlexifry]

tab washer gets yeeted into a pile of other useless shit like 3PDT breakout boards.

 

[Bricksnbeatles]

Oh, actually I do drill a hole and use the tab washer on the inside if I’m using a faceplate!

 

[Caedarn]

I've been searching recently for replacement washers for these switches. I was hoping to find something similar to the washer that comes with the switch, but a smaller outside diameter and obviously without the tab. "Standard" hardware store flat washers don't look right to me on a pedal. I saw the 'fancy' ones at Love My Switches, but don't really want $.50 washers. If anyone has a good source, can you please share it?

 

[owlexifry]

bugger the washers... just get a dress nut

https://www.taydaelectronics.com/dress-nut-for-toggle-switch-1m-series.html

 

[Feral Feline]

Washers are free with the SPDT, dress-nuts are not.

 

[keevohn]

I ditch the flat washer and just use the nut on top. Lock washer goes goes on the inside, natch.

 

[darwin999]

What is the purpose of the notched washer ?

It's to prevent the switch from getting rotated when in use (which could generate a short, etc). If you drill an additional tiny hole in the enclosure at the right distance from the ~1/4" hole for the switch, then that pin on the washer would fit in that hole plus the notch fits into the slot on the switch, holding the switch fixed in position. That would be the professional way to do it, but most of us are "lazy". And if the switch is soldered direct to the PCB, that will also prevent rotation.


Added comment: if the switch instead had a rectangular opening, then you wouldn't need this as it can't rotate. But now you would need a rectangular punch to make the hole, which isn't very DIY-friendly. There are many other ways to preclude rotation, if you look at panel switches - some have round holes with a notch, and so on. Again, most of these schemes are not DIY-friendly. The 2 circular hole method is probably the most DIY-friendly, as you can use 2 drills for the holes.