Just bought a TF Gold P40.The flaps are on the plane but don't work.Are they supposed to work with a servo each or one servo and bell cranks or one servo androds going to each flap?

Flaps are shown to have one servo per flap, page 50 of the manual...

http://manuals.hobbico.com/top/topa0120-manual-v2.pdf

Thank you very much. The manual was just what I needed to set this up. A picture is worth a thousand words. Thanks!

I bought a P-40 red box ... in fact the guy had two of them already built. The first one had quite a few issues. The glue was comiing apart evrywhere, ... especially in critical areas and strees points. I decided to pull the skin off the wings and remove the servos since the skin was just pulling off the ribs any way. They had one servo for the flapps and one for the ailerons. They used the bell-crank style design for flaps and ailerons. I changed that completely. Now each control surface has its own servo. I am just about ready to fly the plane. I'm glad I checked the pushrods and bell-crank stuff. The guy soldered the pushrods together because they were too short. He pieced them together and the solder joint didn't bond completely to the metal. They were sure to fail. Just vibrations alone would have caused them to break . I saw some slimline servos that are perfect for this type of conversion. They lay flat into the wing. I'll probably try them on the other plane when I get around to it. This plane I used the HS-81 (4) in the wing and one for rudder / one for elevator.

Originally Posted by screilly

I bought a P-40 red box ..... I saw some slimline servos that are perfect for this type of conversion. They lay flat into the wing. I'll probably try them on the other plane when I get around to it. This plane I used the HS-81 (4) in the wing and one for rudder / one for elevator.

This plane is a bit large for the HS-81 servos. You should use a standard size servo on the rudder/elevator. Probably will be okay on the wing surfaces, but .....

Hemikiller, .... I moved the servos all the way to the back / tail section when I did the servo modification. The rudder and elevator has only about 4" linkages instead of the long push rods to deal with. The torque specs seem to be within reason and I used the inner hole at the servo-horn and the outter hole at the surface control horn area ... so the geometry would give the best leverage combination. Do you think the HS81 is still under sized? Other people are saying that it is Ok? I don't want to take a big risk ... It aint worth the cost. I was trying to use stuff I already have.

HS-81s servo gears are fragile, I've broken them just by dropping a servo on my work bench.

I still think a standard size servo would be best. That plane weighs, what around 8 ~ 10 lbs? For planes like that, you would be better off with Futaba S3003, S3004, S3010, etc. I've used them for years and while they are not the ultimate servos, are very rugged and have enough power and size for a 60 size plane.

How about if they were metal gear? They are not but maybe that would be an alternate solution? I was thinkin that since they were moved all the way back to the rear of the plane, ... the standards would be too big and heavy. I also put them on each control surface. If the gears wont hold up then i need to either change them to metal gear or find something that will fit into the same space. Any ideas on the gear thing? can metal gears go into the same case as the plastic version or do I need to swith the whole unit? If I need to switch the whole thing out, ... what can I use in tha size?