Stackpole latching keys

nerdhouse · 13 Jun 2022, 02:51

Hello everyone,

I recently got an old dumb terminal with stackpole switches. Luckily none of the stems are cracked, and all the switches work well, except for the two latching keys.

They have a little wire that interfaces with the key, and when I get it seated correctly the key will latch/unlatch once or twice, and then the wire falls up, away from the key, and the key pops out. Is there supposed to be tension on this wire piece? Is anyone familiar with this issue? I don't know much about vintage keyboards, so I'm really not sure how to fix this.

Here are a few photos showing the key and wire mechanism. (Please ignore the small piece of paper, it's just there until I resolve this issue with the key)

Thanks!

jsheradin · 13 Jun 2022, 03:27

Is that an H19?

I'd bet the wire just isn't engaging the cardioid track enough. I think the spring is supposed to push the wire into the side of the slider. You might just need to bend the wire a bit to get it to bite. It also looks like there might be some crud in the track that could be kicking the wire out.

Here's a working one for reference:

Spoiler:

nerdhouse · 13 Jun 2022, 04:16

It is an H19!

I don't think the spring is tensioning the wire at all. I will mess around with it when I can and report back. Your pictures seem like they will be extremely helpful.

Thanks very much!

nerdhouse · 13 Jun 2022, 04:38

Got it!! Your drawing did the trick. The spring has to be seated just right, or it doesn't tension the wire at all! Thanks so much!

It seems like the springs aren't quite strong enough to keep the wires in place 100% of the time.