Wierd PCB reset PB switch dimensions

After an exhaustive search tonight, it seems PCB mounted push buttons essentially all are on 6.5x4.5mm centers, no matter where you buy them

How is that, when 2.54mm spacing is 'the norm' for everything else?

Standards are great because there are so many to choose from. 2.54mm is fairly common for certain components, but I'd stop short of calling it the norm.

JohnHoward:
After an exhaustive search tonight, it seems PCB mounted push buttons essentially all are on 6.5x4.5mm centers, no matter where you buy them

How is that, when 2.54mm spacing is 'the norm' for everything else?

Because of the mechanical shape of the switch I suspect - anything that's PCB mounting
can have any footprint it likes, so long as its documented in the datasheet. If you want 0.1"
pitch you use a break-out board. These push buttons are nominally 1/4" square and the
leads come out on two sides (so they cannot be on a square grid anyway)

Very few components I use these days are 0.1" pitch, lots are SMT with 0.8, 0.64 and 0.5mm
pitches, and I generally use break-out boards for prototyping.

Those push buttons will just about fit into a breadboard, with a tendancy to pop out again.
For stripboard you can enlarge the holes a little to help with the fit.

Bought some -- I just hope the leads can be shoehorned into a 0.1 O.C. protoboard. Fortunately they're dirt cheap so it won't be a big loss if they don't.

I'd be surprised if a shoehorn were even necessary :smiley: I've used them on protoboard without much trouble at all.

Let's hope. I don't even own a shoehorn!

Can always solder on some wire cut off from other parts (LEDs, resistors, caps) to make the parts a little more breadboard friendly.