Hello Gordy Burying your servo deeper (higher) into the wing raises the front end of the pushrod, causing the pushrod angle to change. To get exactly the same servo/control surface action as if the servo were flush to the bottom of the wing you should rotate the control horn mounting through the same angle, rotating about the centre of the hinge, so that the angle between the pushrod and the line of holes in the horn (which should point at the hinge pin) remains the same. But that's if you had optimised the pushrod/horn angle in the first place. (aileron horns and output arms pointing forwards, backwards for the flap horns and arms, and fine tuned) The worst case would be with a deep section wing and short pushrods. With a shallow molded wing the pushrod angle would probably change very little, causing no measurable change, the way most modellers fit their gear. You may be a perfectionist though. I'm sitting late at work designing a self-dumping wheeled loader bucket system, rotating hydraulic cylinders and their lines of action all over the place on CAD, so I guess this discussion is kinda pertinent to me at the moment. :-) Regards Richard Knott Bell Equipment Co. South Africa Wheeled Loader Marketing & Specials +27 (35) 907 9325 (ph) +27 (35) 907 9611 (fax) +27 (0) 82 775 8061 (mobile) [EMAIL PROTECTED] wrote: > In a message dated 6/6/00 1:19:16 PM Eastern Daylight Time, Raschow writes: > << How does it affect the throw and power of the servos, both having the > same > two hole arm and the wing is about 1" deep. the flap horn about 1/2" high? > >> > > Not at all - length of servo arm and length of flap horn to the hinge are > what are important - these don't change with which skin is used for anchoring > the servo. >> > Thanks for you comments, > > Since I have done so many foam cores and the servos end up flush with the > bottom, I assumed that it was the 'correct' way to mount them. But lots of > guys with moldies seem to be just gluing the servo to the top skin, deep > inside the wing. They still just use the 2 hole horn. > > Math isn't my thing, so I figured I would ask some of the engineer types out > there. > > Anyway, I have been shimming my servos in the moldies to bring them flush > with the bottom skin like my bagged ships figuring that was the 'correct' > thing to do. > > To me it seems like the servo mounted in deep would be pulling against the > hinge line, trying to pull the flap service forward into the wing, instead of > up in a rotation. > > What do you think? > Gordy ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept by MIMEsweeper for the presence of computer viruses. www.bell.co.za ********************************************************************** RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
