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Design => Stunt design => Topic started by: walterbro on October 23, 2009, 09:50:29 AM

Title: Design of adjustable elevator
Post by: walterbro on October 23, 2009, 09:50:29 AM
 I have tried several adjustable ways to set elevators relative to flaps.
none have been easy to use. I would like to design a really easy to use
system that is safe for high wind conditions and long life. There may be
some posts on this that I did not find. Can some one steer me to a system
that really works and has been tested?

Sincerely,
 Walt Brownell

   
Title: Re: Design of adjustable elevator
Post by: Trostle on October 24, 2009, 09:50:38 AM
What have you used and what did you not like?

A slider on a slotted horn is about as easy as it can get.

Keith
Title: Re: Design of adjustable elevator
Post by: walterbro on October 24, 2009, 11:12:17 AM
Hi Keith - I have tried a slotted horn and that is OK for changing ratio
of elevator to flap movement. It doesn't help when you need  to adjust
a change in  the neutral position. For example, add a little down elevator
to eliminate inverted flight waviness. It may also be required when the moisture
level changes the fuselage length. The change in length of the pushrod is
what I want to do in an easy manner that is safe for the life of the ship.

Sincerely, Walt

 
 
Title: Re: Design of adjustable elevator
Post by: PerttiMe on October 24, 2009, 01:02:03 PM
So you need adjustable pushrod length. I think RC pattern flyers have been using threaded pushrod ends and clevises for a long time. Something like this:

http://www.centralhobbies.com/control_linkage/pushrod.html
Title: Re: Design of adjustable elevator
Post by: rustler on October 24, 2009, 02:32:37 PM
Tom Morris components assembled to his instructions give you adjustable pushrod length.
Title: Re: Design of adjustable elevator
Post by: Bob Reeves on October 24, 2009, 05:24:05 PM
Tom Morris components assembled to his instructions give you adjustable pushrod length.

Yep, just order a reverse thread insert and it makes the pushrod into a turnbuckle, easily adjusted with a small wrench. In a pinch the car guys also use a 4-40 reverse thread. Think it's a steering part that has a standard thread on one end and reverse thread on the other with a small hex in the middle. Problem with it is the hex part is so small you have to buy a special wrench.
Title: Re: Design of adjustable elevator
Post by: walterbro on October 26, 2009, 07:54:42 AM
Thanks Guys - I have found Tom Morris's "Nifty New Product" . This allows you
To adjust neutral and throw ratio through one small hatch without disconnecting
anything. This is what I wanted.

Sincerely, Walt