Hi there Guys Im new on this page and I want to show you my first model kit builded by me,, its a Great Planes .40 Piper Cub J3, Im using a .65 golden night saito engine on it, never tried a 4stroke before and Im not sure which prop size to use yet, some people told me that I dont need much on this plane because it floats on the air, what do you guys think? Thanks for looking.

Looking good! Plenty 0f engine for this plane, I'm thinking a 12x6 for the prop, flying it around at half throttleor lower for scale flight. I have one of these with a .52 in it and plenty of power. It goes to the field anytime I go, one of my favorite planes, hope you enjoy yours as muuch as I do mine.

Niice', I was looking for a .52 engine but  found the .65 for the same price, I will try 12x6 prop and see how it goes now im waiting for a few part to get the plane done and visit the field', Thanks for the reply

G'day

I have had a few Saito 65s and I still have some Saito 62s in my collection of 14 or so Saitos. I would put a 13 x 6 on the 65 as a starting point or better a 13 x 5 if you can find one. The 5 pitch prop will give you plenty of pull while allowing the Cub to slow down for landing.

One of the down sides of having a slightly large engine is that you need a slightly large prop and it will still be producing quite a deal of thrust even with the engine near idle. This can cause floaty planes like the Cub to not want to land. A lower pitch prop gets round this problem.

The other "interesting" thing about Cubs is their tendency to suffer from "adverse yaw". You try to turn the plane to the right with the ailerons and it either goes straight on or it turns wide with its tail hanging down. The cure is to use rudder as well in the turn. If you have a computer radio, you can use a mix to add some aileron to rudder mixing which will help with this. It is best to make it switchable so you can turn it off. Otherwise, if you try to roll the plane, you will get a very nasty and untidy roll at best.

Have fun with your Cub and the Saito.

Mike in Oz

[X(] WOW..!!

Gorgeous job..! I'm jealous of both your plane and your engine...[8D]!

Great info'   it makes sense and  appreciate your help guys, I saw the 13x5 prop on web and thinking of buying one and try all the sizes that you gave me guys and see what happend' also im using a fasst transmitter so I can try the mixing setting with the aileron with the rudder, Dont be jealous my friend haha ha just gota little luck when I was looking for a new plane and engine but I think this is the first and the last kit i gonna build, the next one will prefer an ARF kit cuz the regular kit takes too much time''''  Thanks Again Guys!!!!

Another thing excuse my english im not good with it yet'

I built the clipped version with a magnum 70 4 stroke.. a 14x6 is what I used and it worked great but the 70 is a bit bigger but not much.

I would not mix the aileron and rudder... you will need control of the rudder by itself on takeoff.. as the cub is very squriely. As far as flying.. learn to use the rudder independently...your pilot skills will be much better for it. For example cross wind landings, etc. This cub will groove better with a bit of rudder during a turn.

I routed my exhaust out the bottom with a diverter as well.. left virtually a clean plane end of day.

Cool Thanks'

Hi!
A 13x6 (APC, RAM or Graupner Sonic) is what you should use if you fly at sea level!
12x6 is to small for that engine!
But I hope that isn't the plane you are gooing to learn on?! Get a high winged trainer first!!!!

No is not my first plane, this is my first model kit builded I have been flying around 8 years but once or twice a month