RE: Wagstaff wingtube problems
Use dry graphite every time you put the wings on. Put some on the tube itself and some inside the wings. Work the wings back and forth around the tube to get it evenly distributed. It helped the first time I did it and more every time I repeat the process. I've been doing this the last 6 times I've flown and they are working beautifully now.
I started with the same problem you describe and I have the dreaded cardboard tubes.
Clean-up becomes a little more of a problem if you get carried away like I do!
Good Flying to you!