Bird of Time- wing tips
 

I've built a Gentle Lady and a Sagitta 900 some years ago. Both make a point of inducing washout to prevent wing tip stalls. The instruction manual with my BOT kit (currently abuilding) makes no mention of this. The tip of the wings are nearly all D-tube. It's hard to imagine that Monokote could twist those puppies to any degree. If they do need washout should the outboard trailing edge be wedged up before the top sheeting goes on and, if so, how much? Any thoughts, anybody? Thanks in advance.

RE: Bird of Time- wing tips
 

Well I did it with mine just like you said. I packed the triling edge up as I built it on the board, then put the top sheeting on. Its about 10 years ago but I guess I added 3/16 to 1/4 inch at the tips.
A friend built a BOT at the same time and so I have flown this model both with and without washout. It is a very forgiving model without washout but with washout it is outstanding. My model can be mishandled in a ludicrously crass way without biting. This means that I can thermal very slow and low without fear.
I have much more sophisticated all moulded models these days but I will never be without my BOT.
Regards,

John.

RE: Bird of Time- wing tips
 

Dave's original plans call for built in wash out in just the last four to six inches.

RE: Bird of Time- wing tips
 

Bill,

I did the same as John Mac - added 1/4". Flies great.

papermache

RE: Bird of Time- wing tips
 

Bill,

I don't know whos BOT you have but, the Skybench Aerotech Big Bird BOT does not call for any wash-out. It uses the Selig 3014 airfoil and doesn't have tip stall tendencies.

Thermals,
TomF