We should not have to spend time adding, gluing, soldering, welding, taping, dimpling, or using any other technique to make a particular pen kit perform as it is (poorly sometimes) designed to perform. There are too many other excellent kits that perform as designed to stress over a kit that is not up to par. I have sold and/or given away several hundred sierras (Berea's original) and don't remember the last time I've had a problem with the (original Berea) sierra. Maybe I've been lucky. I can't say the same for other "sierra" clones as Ed has so correctly called them, especially the ones from China.
Do a good turn daily!
Don
Don consider yourself lucky my friend. This discussion of the sierra kit( Now this is the one that has the tranny srewed to the lower barrel) Has been the topic of dicussion here many times. I don't care who sells it because it still has the same flaw and that is the tranny will get unscrewed especially if the operator has a heavy hand and then forgets and pushes the top tube on and now the tranny is pushed too far into the top you have to be pretty ingenious to get it out. I use a sierra as my everday pen and have had this happen. I am the pen maker so I know what to look for but the buyer may just throw the thing away and you don't hear from them. Doesn't mean it didn't happen.
The ones with the turning point in the cap are the best and no problems with them. I just need the Vista kits for so many thing and am stuck with that design.
As to the primary poster problem I still am foggy as to what you say is the problem but if you found a fix then good for you and hope it works. May have been a bad run of whatever is wrong. Sure would like to have seen a photo as to what you are talking about because there is only two push in points. Not sure what you mean about the inner part of the finial. This comes already together. Now if that is what is falling apart then that is a whole other story.
I agree and have said this many many times we should not have to glue, improvise or anything when putting kits together. The spinning clip is another prime example. There again Berea makes these kits as well as others and all are bad news.