Chazzy-- from all that's described. Since you can't push it in, I'll speculate its maybe a little jagged surface on one, or mostly likely both surfaces, creating minute "interlocking" points that causes the sticking.
Best way to verify (as my eyes need reading glasses these days is one of those cheap digital magnifier from online.. 500-1000x should let you see everything there is.
Ok here comes the wall of text and hope I am making sense here...
From the orientation of your pic above.. do you feel the stick more from right at the edge of the lock insert? If it is --what i had done before was to work only on that area. Couple of swipe on sandpaper and then mostly with a strop. Just rolling/ rounding it ever so slightly. It's really really little I must emphasize.But it was on an insert that can be taken out.. Here you mentioned the insert seem to be pressed fit and if it cant be remove and put back easily enough than it would be awkward to do what I did. when I work on that knife I posited that the very edge of the insert will have the max path of resistance of any kind as it is first in last out and moving through the entire full lock on surface with the blade side. By slowly disengaging, if the culprit is really at the edge-- u should feel it and the "click" due lock stick would kick in later.. Else if it seems to be more towards the left of the lock insert surface-- that I will also check the lock surface on the blade more carefully.. Kinda tricky.
One other area I also look at is the right side corner of the lock insert. Inserts and their cut out comes in all shapes. Some are totally exposed on underside and lock face (like the F95) as it is secured by the insert screw.. Here the F3 looks like its pretty much "wrapped" up leaving only the lock face portion exposed. If that corner is sharp ( can't see too clearly from the pic)-- that's where I had problem with lock stick on some knives before.
Kinda late -- just quick snap with my crappy cam phone.
To illustrate.. knife on left below doesn't have an insert (I think the maker puts a carbidized surface or something like that on it) but that right corner was sharp and it was sticky when I first got it from a trade.. its been "rounded" off if you can see from the pic.. It was hard to get at and what i used here was actually one of those rust/ stain eraser from a dollar shop.. and when I felt enough was smoothed off-- rest was just applying the good old pencil trick.. no stick from then on. On the right is the insert on the F95-- its nicely bevelled on both sides so there wasn't a sharp corner (or maybe it has already worn off by the time I got it) and never had sticky issues so far.
Best way to verify (as my eyes need reading glasses these days is one of those cheap digital magnifier from online.. 500-1000x should let you see everything there is.
Ok here comes the wall of text and hope I am making sense here...
From the orientation of your pic above.. do you feel the stick more from right at the edge of the lock insert? If it is --what i had done before was to work only on that area. Couple of swipe on sandpaper and then mostly with a strop. Just rolling/ rounding it ever so slightly. It's really really little I must emphasize.But it was on an insert that can be taken out.. Here you mentioned the insert seem to be pressed fit and if it cant be remove and put back easily enough than it would be awkward to do what I did. when I work on that knife I posited that the very edge of the insert will have the max path of resistance of any kind as it is first in last out and moving through the entire full lock on surface with the blade side. By slowly disengaging, if the culprit is really at the edge-- u should feel it and the "click" due lock stick would kick in later.. Else if it seems to be more towards the left of the lock insert surface-- that I will also check the lock surface on the blade more carefully.. Kinda tricky.
One other area I also look at is the right side corner of the lock insert. Inserts and their cut out comes in all shapes. Some are totally exposed on underside and lock face (like the F95) as it is secured by the insert screw.. Here the F3 looks like its pretty much "wrapped" up leaving only the lock face portion exposed. If that corner is sharp ( can't see too clearly from the pic)-- that's where I had problem with lock stick on some knives before.
Kinda late -- just quick snap with my crappy cam phone.
To illustrate.. knife on left below doesn't have an insert (I think the maker puts a carbidized surface or something like that on it) but that right corner was sharp and it was sticky when I first got it from a trade.. its been "rounded" off if you can see from the pic.. It was hard to get at and what i used here was actually one of those rust/ stain eraser from a dollar shop.. and when I felt enough was smoothed off-- rest was just applying the good old pencil trick.. no stick from then on. On the right is the insert on the F95-- its nicely bevelled on both sides so there wasn't a sharp corner (or maybe it has already worn off by the time I got it) and never had sticky issues so far.
In to work I go with this fantastic blade in my pocket
