Originally posted by hjoseph7 The reason I did not throw it in the trash is, after I removed it from the K-5 II, I noticed that inside the box it came with, there was a key. You were supposed to remove the adapter with this key, but I didn't know that back then. So I put the adapter back in the box and threw it somewhere hoping it would disappear on it's own. The other day, I found that box while I was looking for something else, so I decided to try it on on the K1000.
I attached and detached the adapter maybe 10 times with the magic key and everything seemed to be working fine ? It wasn't until I attached a lens to the adapter(while it was on the camera) that it locked to the camera body and would not come off even with the magic key ! I'm not sure why they sell garbage like that in the first place ? Maybe because the Pentax adapter cost between $75-$150 depending on your source.
Yes, it's a problem that the aliexpress / fleabay versions are not particularly well machined. Added to that, they have a little spring with a protruding screw and it's usually that screw that causes all the drama.
I have a cheap one and I have removed the screw and the spring. The disadvantage of that is that there's only a bit of friction holding the thing in place, but I can live with that if it means I never run the risk of this sort of catastrophe.
So, my advice is, either buy the real Pentax one or get rid of that spring and protruding screw. What I have not tried is to see if replacing the screw with a screw with a flatter head fixes the problem.
Sorry if my previous reply appeared unkind. Not my intention.