How to Make a DIY Cable Release Socket

I have several cameras with awkward switch/lever style shutter releases and no cable release socket. Maybe the most obvious example is the Holga 120, but the Kodak Brownie Starmeter is another. Something has been tickling my mind for a while, wondering if I can repurpose some commonly available object to create a plunger-style release that would be reachable atop the camera where I find it more convenient, as well as accepting a cable. (I know there was an accessory for the Holga, and you can still buy 3d-printed clones, but I'm trying to think of something less cumbersome and which I could apply to other cameras too.) Photo of the Holga with an inset of the Brownie Starmeter, in case folks aren't familiar:



To give an example, I feel sure I have seen ballpoint pens with "clicky clicky" thumb buttons on their non-inked end, which are thick and have a metal cover loosely fit over a plastic rotating pusher rod beneath. I think if I go into an office supply store I can likely find one with about the right dimensions, and then it would be a matter of cutting it apart, introducing a threaded hole on top perhaps by just drilling a hole and bending its rim into a spiral like I see sometimes with sheet metal parts intended to hold a screw, and gluing it onto the camera. Crude, but I think something like that could be made to work. And maybe if I go wander the plumbing or wiring section at the hardware store I could find something even better.

But I wonder if anyone's already thought of something good for this. I searched, but I can't find anything. Ideas?

Well I restore Thornton Pickard roller blind shutters they mainly used a pneumatic release but all the rubber parts are long perished. Late ones had tapped release arms to allow a cable release to be used. So I tap the arms with an M4/.7 tap, that works well.

Ian

Tapered cable release threads are 50 threads/inch. Since the threads are tapered, there is some latitude in the thread pitch you pick from readily available taps.

Browsing around, I stumbled upon what looks like a popular mod for a Kodak Brownie Hawkeye: drill a hole in the top of the camera and set an ordinary nut (e.g. to thread onto a bolt) in it, and then a cable release can reach down to the shutter release plunger, which seems like it might have been made with cable release in mind but they didn't follow through. This makes me think I could go to the hardware store and find a nut that a cable release would fit acceptably (as I recall, a lot of nuts actually are threaded with somewhat of a taper anyway).

A M3x0.5 nut is a good fit for a tapered cable release.