I have this nice Warbird I'm putting together and I plan to fly only scale with it. I've built many ARF aircraft with the control horns bolted or screwed all the way through the control surfaces. On this plane I am tempted to cut off the covering around the bottom of the control horn, Epoxy and button screw it in to place so I won't have the back part on top of the ailerons, elevators or, on the other side of the rudder showing.

Will it work?

Just trying to make my plane more realistic. Your thoughts please.


Pete

On a LOT of the newer Great Planes and Top Flite models there is a 1/8" plywood plate on the bottom of the control surfaces. You use a 1/2" #2 sheet-metal screw to mount the horn. The horn is then removed, the holes are hardened with thin CA and the horn is reinstalled.

Many of the planes I reviewed in the last few years use this method and it works very well.

Here are a few of the reviews where you can see this method:

[link=http://www.rcuniverse.com/magazine/article_display.cfm?article_id=1134]Top Flite P-47[/link]

[link=http://www.rcuniverse.com/magazine/article_display.cfm?article_id=870]Top Flite Cessna 310[/link]

Pete,
I have never done this - just using logic.
I assume the wood is balsa.
If so, you would need to satuarate it with CA to give it some strength.
I would still be nervous.
How about cutting a recess on the bottom, harden the wood, glue in the back part and then covering?
Good Luck,
KW_Counter

Sounds like your assembling an ARF? When I build a plane I cut out the balsa area that the horns are going to mount in and add a ply section so I can use small wood screws. It's just adding hard points. There Are other ways but hard pointing is just a very easy way to do it. If it's an arf and the controls area is thick enough you can remove some of the balsa and inlay the hard wood without removing the covering from the top so it isn't seen.

As long as there is a hardwood or plywood mounting point for the horns, wood screws will work just fine. Just be sure to harden the holes with thin CA. I also like to add a little dab of thick CA on the threads when I put the screw in. Not sure if that is necessary but it makes me feel better. I've beat the crap out of airplanes with control horns mounted like this and no failures so far.

I've done as Grey Beard stated many times on ARF's. Pull back the covering, cut a square hole in the balsa where the horn will mount, and glue in a hard wood/ply block into the hole. Then mount your horn to this harder wood with wood screws. Works great and no back plate on the other side of the control surface.

Ken

Yes it's a ARF, and I usually try to improve anything I can when I build them without butchering the plane if I can help it.

The ailerons were epoxied in at the factory with the good nylon hinges. I gave them a good pull and one was well glued, the other aileron came out, I quickly re-epoxied and re-installed the loose aileron.

I'm not sure if the control sufaces are solid balsa or not, they are all pre-covered.

What I am thinking of doing was to use some brand new Nylon Hanger 9 Control Horns (with the 3 screw holes) sand the bottom a little, place them on the control surface, outline them with a pencil, cut the fabric away, hand drill the holes 1/16, put a few drops of thin CA in the holes and epoxy the bottom of the control horns on the control surface, and by using the #2x3/8 Button Head screws, tighten everything down.

Does epoxy soak deep into balsa making it a hard surface like the CA hardens the holes for the screws?

The ARF is a VQ Warbird, the Me-108.

I thank you all for your thoughts and quick response, I like everyones answer so far, I just need to make the right decision.

Pete

Hi!
A good way is to use thin 1,5-2mm Epoxy plate for control horns that you glue in with thin Ca glue.

Sure, but I don't think pull-pull on (for instance) the elevator will add to the scale looks he's looking for.

I have been doing this kind of horn mounting for at least 15 yrs & have never had one break or come loose yet. Everything from fun fly, scale war birds & 1/4 scale pylon racers. I first cut a groove into the moving surfaces leading edge. Then cut or trim the horn to fit inside the pocket formed by the groove. At this point, the fit is kind of loose which is what you need. Next I ruff up the horn surface that will be inside the pocket, then fill the pocket with 15 minute epoxy & fit the horn inside & Adjust its fit with flat tooth picks shoved into the pocket to help keep everything aligned as it needs to be. Wipe off extra epoxy as needed & when dry, you have an almost indestructable mount. And it is invisible from the top surface. Bill

Hi!
Why not!
internal horns are the way to go if you want a scale look. And then wires are the best way of controlling all flying surfaces.

I stand corrected.

I guess I have to think of it this way... I have about $800-$1,000 bucks worth of equipment and time riding on one control horn. I've come to the conclusion that I shouldn't chance it.

I thank everyone of you for your thoughts and experience.


Pete

Hi!
???
Well ! Using epoxy plate (2-2,5mm )control horns , glued in place using thin Ca glue is the best way of doing it!
commercial, plastic control horns don't look nice on a scale plane.