...I almost always go with what feels right vs what the math tables tell me until I am proven wrong.
Ken is management material!
IMHO a 5" bell crank with the same leadout movement as a 4" will provide more force on the flaps at the same deflection which may just move the N-wall a tad.
Yep, pretty much.
I am also a believer in restricting bellcrank movement.
I did this in combat planes so the airplane wouldn't stall when I did a panic turn.
So little is gained by the last 25% or so that it is not worth all the lumber you have to remove.
Or the lumber you have to add in a structurally less advantageous place.
If you reach maximum deflection before the BC arm hits 90 degrees you are putting extreme pressure on hinges,
How's that?
if you reach 90 degrees before full deflection, you are at risk of over-centering.
Not me. I read this when you wrote it before and put in a stop on my latest plane a degree or so before the bellcrank went over center.
I know this from bitter experience. I have a pin just inboard of the bellcrank that hard stops it at 70+- degrees on all of my planes now. That is about 30 degrees of flap and I have never gone to one line no matter how hard I try to corner.
The Netzeband wall is squishy. Your airplane gets hard to fly accurately before you completely run out of control.
And thereby hangs a tale. Netzeband is a town in Germany, possibly where Wild Bill's ancestors lived. Joe Gilbert and I were on the US stunt team for the 2022 world champs in Poland. We had this plan to go to Frankfurt, rent a car or two, attend the Ronneburg contest a week before the Polish events, then drive to Netzeband, look for the Wall, take a picture, then head on to Poland. I can imagine my wife's reaction when she figured out the plot.
Now, I am just waiting for someone with a Sh** hot laser or 3d printer to make a rack and pinion bellcrank.
Too ordinary. How about a self-centering rack and pinion with a Reuleaux triangle pinion?