I know that most of you guys don't fly/try the current rage 3D type models .
I do and here is a bit of "cut and try" info.
I am doing tests on a particular 3D kit which is about 1100 sq in and has a progressive airfoil being same absolute thickness at tip as root -- chord has a taper ratio of 2-1 with a tip thickness of over 18% of chord.
The plane is extremely easy to fly ( very low wing loading of 20 ozs/ft)
The interesting part to me, is that doing very tight flat power off turns --the inside wing stalls as easily or maybe even quicker than a very similar wing but with a very thin wingtip setup . I tried this a few times - just to be certain.
The old saw of a thicker foil has better lift - -just does not appear to be correct-
I never thought it did .
I only mention this as some feel that a thicker tip prevents "tip stall".
On models -I have never found this to be true.
Sounds good tho ---