So, I don't want to use big servo arms... got it. I'll just use the stock ones I am also definitely going to do everything I can to save weight.

One more thing, about the offset differential arms, how do they work/why do you need them?

The offset arm is done to eliminate the differential that would occur because of the way the pushrods angle out away from the servo. With the arm on the top like this model they will move more up than down.

Without them you will get more throw one way than the other and the rolls will not be axial.

So you only need them if you don't want the plane to roll properly

To get an idea how they work, imagine an extreme case with the pushrods out 90 degrees to the output arm. The control surface would only move up!
The idea is to get the line from the axis of rotation of the servo out to the hole in the arm to be at right angles to the pushrod. That gets you close to equal throws both ways. Not quite. but close.


Pat MacKenzie

Oh, thanks! Do the servos come with them or do you have to buy them?

Originally Posted by pmackenzie

The offset arm is done to eliminate the differential that would occur because of the way the pushrods angle out away from the servo. With the arm on the top like this model they will move more up than down.

Without them you will get more throw one way than the other and the rolls will not be axial.

So you only need them if you don't want the plane to roll properly

To get an idea how they work, imagine an extreme case with the pushrods out 90 degrees to the output arm. The control surface would only move up!
The idea is to get the line from the axis of rotation of the servo out to the hole in the arm to be at right angles to the pushrod. That gets you close to equal throws both ways. Not quite. but close.


Pat MacKenzie

You either have to buy them or make your own, they don't usually come with servos.

The kit might come with them, some do. FF mentions supplying them in their kits in the ad:

http://www.fancyfoam.com/index.php?m...products_id=69

You attach the offset arm to a stock arm. I use CA glue and some Kevlar thread wrap

Pat MacKenzie

Originally Posted by pmackenzie

You either have to buy them or make your own, they don't usually come with servos.

The kit might come with them, some do. FF mentions supplying them in their kits in the ad:

http://www.fancyfoam.com/index.php?m...products_id=69

You attach the offset arm to a stock arm. I use CA glue and some Kevlar thread wrap

Pat MacKenzie

Cool.

hey guys i just ordered my first vpp setup for my son from the fancyfoam website. i'll be building it soon but i'm already thinking ahead to what i think is going to be the trickiest part. radio setup. can anyone send me a link to a video/thread/post that can give a first timer some tips for basic setup? i have a dx8 and of course would love it if i could find a dx8 model file that i could download/import and just modify. any tips you guys have would be great
k.t.

Hope this helps,

Free

Aurora9 VPP (Variable Pitch Prop) Setup (6 min 38 sec)

thanks a bunch. that will get me started on the right track. looks like i should call on my heli friends when i start setting this up!
thanks again,
k.t.

Originally Posted by Free

Hope this helps,

Free

http://www.youtube.com/watch?v=EVSnY...eature=related

hmm, service unavailable! Can't see it!

Google the name?

Free

Never mind, the school network just figured out how i got onto YouTube...

hey guys, has anyone made a good build video for the mx2? i'll be starting on my build during the next few weeks and i usually like to watch build video a few times before i build anything. i looked in this thread but didn't see one.
k.t

http://store.higherplaneproductions.com/aj-vol1.html

I have not seen a free build vid for the MX-2, look at the link for some similar videos, the manual is good.

Free

http://tasfoamies.webs.com/buildvideos.htm