Hmmm. Thanks for the lock advice - I'll check with Epic and if the thing is not too much $$$ I might just order a new lock, provided it comes with the rubberish stuff on the inside. Or maybe just get an inner tube pice and glue it there myself.
Epoxy (other than perhaps G-Flex) would probably be my LAST choice to use on the plastic lock - it will likely not adhere well to the plastic. If I had a new lock with rubberr-ish stuff already glued to it, perhaps it might work, but then so would other adhesives that would not form permanent bond with the shaft but that would still be strong enough (contact cements or 3M stuff). Epic did not use epoxy on the insert (on the insert they used some sort of black hard-rubberish glue that melts sooner than epoxy would, the stuff on the lock did not melt so it might have been epoxy or some other adhesive).
Anyhow, might want to follow the comments on Paddling.net for a bit more info since my last post here.
Shortening the shaft from the mid-point (ferule insert/lock) does not seem like a good idea, if one is to chop off more than a cm - the round section of the shaft there is very short - about as short as to allow a secure connection to the round insert in the ferule. Cutting any length there compromises the joint - I saw it with my repair. Now my straight/round section is shorter than what I'm comfortable with.
In contrast, the oval section on the blade side seems longer and can take shortening OK, at least looking from the outside... Forces are higher on the blade connection though, so there should be more care taken to reattach well.
Lastly, it was MUCH easier (1 minute or less) to remove the insert compared to removing the Lock. First off, the lock would not come out at all despite my heating the shaft to a point that the shaft softened. In contrast, the insert came off extremely easy with a lot less heat needed. Second, removing the insert does not damage enything - it can be reused, where removing the lock apparently damages the rubbery stuff that holds it to the shaft and that can't be reused. Third, after shortening the shaft on the insert side (after the insert is removed) seems to be less likely to cause weakening of the connection, because the insert is glued back and would move less compared to if it was not glued but just inserted, as is the case when one cuts the lock side.
So, I would disagree with your advice for specifically the oval shafts on the Epic. Appears what I did (remove the lock and shorten that side) was the WORST way to do it
. Second worst (but easiest, perhaps) is to remove the insert and shorten that side, then reglue the insert. Best, likely is to approach from the blades side and do both sides by the same amount - if my eyeballing things is correct, that should not weaken the paddle at all, where the previous two options do weaken the center joint.