Easily detachable rewind knob on new purchase

Hello! I just purchased a Contax 139 from eBay, and when I was testing it the rewind knob just fell off/onto the ground. So I screwed it back on and though while it does stay, it can easily be loosened/unscrewed. I have two other Contax/Yashica bodies and can’t make the other knobs budge. Is there a way to tighten the knob so it doesn’t budge? Maybe it needs a new washer?
I plan on using this in some crazy angles (think skateboard type shooting) and am worried the knob will just fall off. I got a good deal on this cam so am willing to replace the knob, but I checked out eBay and they’re not cheap. Trying to figure out if returning is extreme. Thanks for your help

A drop of blue Loctite should do it. Don't use the red stuff on small screws or anything that gets screwed into aluminum.

I take it the shaft and knob are left-hand-thread, every time you rewind a film will just tighten the thread a wee bit more.

Loose rewind knobs can be dangerous in cameras where pulling the knob up is what releases the back. If the knob comes off there is little to keep the shaft from getting pushed into the camera. When that happens the shaft is rattling about inside the camera and there is no way to get the back open to re-insert the shaft so you can, er, open the back.

Nicholas Lindan said:

A drop of blue Loctite should do it. Don't use the red stuff on small screws or anything that gets screwed into aluminum.

I take it the shaft and knob are left-hand-thread, every time you rewind a film will just tighten the thread a wee bit more.

Loose rewind knobs can be dangerous in cameras where pulling the knob up is what releases the back. If the knob comes off there is little to keep the shaft from getting pushed into the camera. When that happens the shaft is rattling about inside the camera and there is no way to get the back open to re-insert the shaft so you can, er, open the back.

Click to expand...

Oh, thank you! Didnt think of glue, so simple! Do you recommend the blue / this ? https://www.homedepot.com/p/Loctite...d-Bolt-Adhesive-0-20-oz-each-209728/100371826

Nicholas Lindan said:

A drop of blue Loctite should do it. Don't use the red stuff on small screws or anything that gets screwed into aluminum.

I take it the shaft and knob are left-hand-thread, every time you rewind a film will just tighten the thread a wee bit more.

Loose rewind knobs can be dangerous in cameras where pulling the knob up is what releases the back. If the knob comes off there is little to keep the shaft from getting pushed into the camera. When that happens the shaft is rattling about inside the camera and there is no way to get the back open to re-insert the shaft so you can, er, open the back.

Click to expand...

Rewind knobs are normal right hand thread, other than that, I agree with the blue Loctite and the fact that rewinding the film tightens the knob. There is sometimes a washer between shaft and knob, but I don't know for the OP's camera.

If the knob falls off and the shaft gets pushed into the body (only possible with no film cassette loaded), it is usually possible to use a hook (like a crochet hook) to reach in and pull up the latch so you can open the back and retrieve the shaft. Camera shops may be able to do this for you. I've done it myself, but the last time I tried to instruct a Photrio poster in doing it, he managed to do a bunch of other irrelevant stuff and rendered the camera inoperable.

reddesert said:

Rewind knobs are normal right hand thread...

Click to expand...

Yeah, kinda obvious. Now. With age the number of things that are clearly obvious decreases markedly....