Bipe Flyer

Last year Goldguy showed me the control horns he made for a few of his 1/2A planes.

I tried it out on my Rascal 27 and they worked great, so I drew a diagram to share.

The horns are made from a piece on inner nyrod and a #2 screw. I made a pull-pull setup for the rudder using a 2-56 bolt instead of a screw.

The top drawing is the normal control horn setup and the bottom drawing is the pull-pull setup.

Lynn S

That will work! thanks BF


It could use a small washer at the base of the nyrod to keep it from going into the wood.

rrragmanliam

My Feedback: (1)

Nice idea Bipe. It makes for a tidy looking horn. I saved the pic for future reference.
Thank you

Darren

Andrew

Yeah -- that's a real clean installation. The nyrod is certainly stiff enough, but I think for peace of mind, like Lynn, I would add a No. 2 washer for the .061 planes.

I also really like Bipe's hinge method of wing mounting -- again a very clean approach and you don't have to worry about dowels, rubberbands or crushing a lightly built wing.

We really need to get together a 1/2A Building Tips sticky thread for all the good ideas that show up here. If nothing else, the Tips thread could contain a descriptive entry with a link to the complete thread -- it would keep it manageable and serve as a nice index to the full discussion.

the "other" Andrew

ZAGNUT

My Feedback: (1)

i like to heat and flatten the ends before drilling for the clevis or Z bend.

to get rid of any differential throw you could also use heat to bend the horn forward to the hinge line. a drop of CA would make sure it never rotates....but then you could also just set the servo horn off center



dave

Bipe Flyer

Or just set the EPA on your radio.

rrragmanliam

My Feedback: (1)

I absolutly agree. I used to twist myself in knots trying to get horn hingeline alignment perfect and adjust then reajust, then re-readjust linkages and such because that's what you were "supposed to do". I fianally just said screw it and now go with the close enough is close enough plan and use my radios features!

Darren

BMatthews

Doesn't the EPA only affect the end points? That would still leave a bit of differential in the response prior to the end points being reached.

For myself I'd just skew the output arm or wheel to compensate. One or two adjustment notches angled to the rear of the model should match the angle up closely enough. I'm with Darren about the "close enough" but it's so easy to just put the arm/wheel on at roughly the same angle that it's not a big deal.

Bipe Flyer

Another factor to consider is that often we need to add a click or two to trim a plane which adds differential.

I just checked the elevator on my Rascal, and there is indeed differential. The elevator can move up 7mm and down 6mm.

On an elevator it shouldn't be a problem. On ailerons it may be a good thing. I inadvertently solved the differential problem by using the pull-pull setup on the rudder which has no differential as far as control surface deflection goes. As the rudder moves, the pulled line remains taut while the other line slackens very slightly. The difference is only noticeable by strumming the lines. The slight difference is probably a good thing as it prevents binding.