whenever I ask a question it is quite gratifying to see the answers roll in. Do people get upset if you dont post a thanks somewhere in the thread, or is it considered an unnecessary bump?
(or in another way, does the board expect a thanks, or take it as read)
Your mother was right: It never hurts to be polite.
It’s one of those little niceties that grease the wheels of social interaction. Why not? You wouldn’t thank someone who did you a little favor?
your humble TubaDiva
PS Thank you for writing. 
I always say “thanks.” Otherwise, how would people know I made it back to the thread and read their responses?
No, the board does not take it as read, because the board has no way of knowing whether you even came back to your thread and read the answers. Some people don’t, ya know. Some people wake up at 2 a.m. with a burning desire to know all about the Treaty of Westphalia, but come the next day, they’ve forgotten all about it. Which is annoying to the person who spent time Googling for it, and who keeps going back to the thread the next couple of days to see only his lonely little thread-killer post at the end. Recognition, dammit! We want recognition! 
So your “thank you” is not only common courtesy, but it also lets us know that your question was important enough to you that you came back to see if anybody had an answer.
And it also has the added benefit of making us predisposed to answer your question next time. Some folks get a reputation for drive-bys which they never come back to, and those folks eventually tend to not get a lot of responses.
So, scm1001, does that answer your question?
Did he ever return,
No he never returned
And his fate is still unlearn’d
…
He’s the man who never returned.
All together now!
It’s common courtesy. If you ask a question I can answer, I may be able to do it off the top of my head, but more often it’s something half-remembered that needs recourse to my groaning shelves, with a bit of judicious googling to back it up. I’m not expecting a medal, but if I can take the time to research and reply, the OP can surely manage a quick “thanks for the info”.
many thanks everyone for enlightening me. I shall religiously give thanks from now on!
Poor Charlie!