Teac 3440 Tension Setting?


I've been transferring tapes and sometimes I have to mix 7" and 10" reels while doing so.
My question is regarding the reel/small/large setting.
I would think this is tension control for the reel, but for which one, the take-up?

I'm asking because while transferring a tape today (with the 7" as the supply and the 10" as the take-up), there were no issues.
I then flipped the tape over, and the positions were reversed.
But whenever I went from FF to Play, the tape would wrap itself on the inside of the reel (hard to explain, but it was visible through the cut-outs of the reel.)

The above control was in the large setting; is this wrong in this instance?
I don't have an answer for you, but I'll be watching, as I have a similar thing happening with a 34B. If I rewind and hit stop, the right hand (take-up) reel continues moving for about another 1/4 turn, causing the tape to let down on the tension arms, and I have to wrap it back up a little to re-engage them, or the machine won't play. I just ran into this yesterday, so I don't know if the problem is a brake on that side, or what.
No rhyme or reason with this - the other day I transferred a tape with no issues.
But when I went back to check something, this happened twice, stretching the tape in both places.
Thank goodness I got the transfer first.
I'm now using small reels with small reels, which I hope will help somewhat.
Happened again today.
What I'm thinking is it has something to do with the tension the Teac is leaving on the reel because it's usually after I play the first side.
(What I'm failing to do is run the tape through before playing, which is a standard precaution.)