Would it be better to scale up the airfoil as well?

[guitchess]

I recently built a 140% version of the mini Corsair. So far, it flies great. There is one thing I was curious about though. I didn't scale up the airfoil profile. While the spar is wider than it was, I still only used one layer. So while the cord and the span are scaled up the thickness is not. Would it be better to scale it up as well? If the airfoil is thicker, it would create more lift but more drag, right? More lift lowers the stall speed, but more drag lowers it, right? How do you achieve optimum airfoil thickness?

 

[dgrigor02]

IMO: Difference between roughly 5mm and 7mm thickness would be pretty negligable. I wouldn't mess with trying to scale the spar thickness.

I personally would prefer it that way, I'd rather have a bit more speed and less lift.