My 580AL is leaking between the aluminum grip and the threads the cap screws into. It's a very little amount, but enough to stain my hands.

I have not used it in months, and a week ago disassembled and cleaned it before using it again.

I emptied the ink, cleaned it again, and screwed it tighter. I was wary to avoid damaging it (as TWSBI pens are prone to cracking). Still, this occurs.

Some searches yielded that I should apply silicone grease to the threads, but I am not sure if this is the solution and perhaps more importantly have never done this before, so I wanted to be sure before attempting.

My Rose Gold 580 does not do this, nor do any of my other pens. I'm not too upset over this, as I purchased the 580 because it was cheap and replaceable.

Any help would be greatly appreciated.