Yeah, I'll give a blu-tac dab a go now. I also have some electronic cleaning polymer goop stuff which has been basically useless until now, but it's in storage. I think blue tac is possibly the quickest solution seeing how difficult it is to wipe the fine threads.
...well I gave it a go, not because I needed to but because I wanted an excuse for some kush
It works perfectly, requires little effort too.
You can also use it to clean the notches and +\- pretty effectively.
Terrible macro shot but the gist is there.
I had rarely cleaned my other hoppers back end as it stays cool, but it had a lot more dust in it. It can act as an abrasive agent destroying the threads so it's best cleaned out.
The kush was strong. It's too early in the day