3Dfoamy.com F-18 setup question
 

I just built an F-18 from the 3DFoamy.com plans and got it in the air (barely) The plane flies, but it is all I can do to keep it in the
air. It seems very underpowered and it is very hard to make it climb. I have to fly it with full up elevator and wide open throttle and
still can not gain altitude.
Nose heavy ? Tail heavy ? or just to heavy everywhere ?

Here is my setup.
The plane is made from fan fold insulation. (from lowe's) It is a little on the heavy side at a little more than 18 oz, although
I have read other posts where people claim their's weights 20 oz.
Himaxx brushless 2015-4100
4.4:1 Gears
GWS slow flyer prop 9x7
EFlite 20 Amp brushless sensorless ESC
Hitec HS-55 servos x 3
Hitec 555 receiver
Kokam 3s1p li-po

Any suggestions ?

Thanks much.

RE: 3Dfoamy.com F-18 setup question
 

It's really hard to say trying to visualize, not seeing the plane in person. But yeah it's a high possibility that the plane could be tail or nose heavy, but usually that's obvious. But I'd first check the throws. And see if you're getting enough or recommended throws in your elevator. I had this problem with my Wattage Mad Max. It seemed nose heavy, but I barely had movement in the elevator because of play in the control horns and pushrods. You may also want to get rid of that slow flyer prop if you're using that Himax brushless engine. Try maybe an 8x4.5 composite prop, and be sure it is balanced correctly. At our local flying field that's a big problem for beginners, prop not being properly balanced. See that there is no vibration, or funny noises from the engine. Lastly if you are sure the engine is operating correctly at full rpm's, check the tail fin, stablizer, rudder and wing proportion and see that it is all aligned straight and not crooked.

Goodluck:)

RE: 3Dfoamy.com F-18 setup question
 

I should also note that since I am new to electrics, I used the recommended setup. The only thing I changed was to use
an EFlite 20 amp esc instead of the suggested Phoenix 25 esc. In fact, this combo is referred to as a "great combo" so I
can't help but think I have something wrong with weight/balance or construction. I am pretty sure I have enough throw in
all the surfaces but I am a little concerned that the elevators are "flexing" in flight. I may add some tape or a carbon rod
for strength, although it is already heavier than I want it to be.
I also noticed that after the flight, the battery was very HOT, too hot to hold in your hand for very long.

Is this normal ? This is my first time using li-po batteries.

RE: 3Dfoamy.com F-18 setup question
 

MJ you do have a great set-up. There is something else way wrong, can you post a photo of your plane? I have built a bunch of these from FFF and use the same set-up. I am unsure about your gearing I think you should be using the C gearing (5.3:1). 9X6 or 9X7 prop are fine if you get the right gears. I know it sounds obvious but are the motor and prop spinning the correct direction? Feel free to pm me with your questions. I am in the final stages of putting one togeather this week and can take all the photos you may want.;)

RE: 3Dfoamy.com F-18 setup question
 

Thanks vicman, I'll post some pictures of it tonight.
I assume everything is correct with the motor orientation or It would not be flying at all... ?

RE: 3Dfoamy.com F-18 setup question
 

Ok, flew it again today after moving the battery forward just a little bit. It flew better, but still hard to handle.
I am also having to hold a lot of right aileron to fly level.

Here are a few pictures.

RE: 3Dfoamy.com F-18 setup question
 

Nice plane jack. We still need to fly sometime. I am out at intergraph alot now. (ERRM when my plane isn't needing repairs[:@])

RE: 3Dfoamy.com F-18 setup question
 

I was just thinking about that today Chad, I was working at Intergraph all day !

RE: 3Dfoamy.com F-18 setup question
 

Man! If you ever are out there and see someone flying go out there. Most of the time it is me and my friend or me and my parents. Just good lazy flying

RE: 3Dfoamy.com F-18 setup question
 

I think your antena wire running from the wingtip to the vertical may have something to do with that one.
I see you are using the Himax gear train (good choice). Have you considered using the C gearing like I mentioned? I think this will give you the amount of power you are looking for. I locate my battery all the way against the nose with an extension wire going back to the sc and rx. The plane should balance out on the spar at the fuse sides. Can you take a photo from the side?
If I am looking at the first pic correctly I think you need to turn your prop around too. It should face forward just like if it were mounted on the nose and you will reverse the motor direction.;)

RE: 3Dfoamy.com F-18 setup question
 

vicman,
Should the prop be mounted on the motor as if the motor were installed forward, or mounted on the motor with the prop FACING
the front of the plane ? It is currently facing backwards, i.e. the curved face of the prop is facing away from the tail of the plane and the motor is running backwards.

Also my CG is forward from the spar, I will move it back some more today and try again, if it isn't too windy.

Thanks

RE: 3Dfoamy.com F-18 setup question
 

jack,
Are you gonna be in madison tommrow?

RE: 3Dfoamy.com F-18 setup question
 

Chad, yes I will be at Intergraph all day.

Vicman, how do you route your antenna, and what is the ratio for "C" gearing ?

RE: 3Dfoamy.com F-18 setup question
 

Jack,
We will be flying sometime during the day tommrow out there. I don't know if i will fly because i still have some repairs, but we will be flying and i will be out there. Come and say hey to us if you can. I will PM you.

RE: 3Dfoamy.com F-18 setup question
 

The front of the prop should face the front of the plane and then you will run the motor backwards. C gearing is 5.33:1 or the 64T gear set. I run my antenna out the front of the inlets and hot melt glue it to the side of the fuse. The CG is 2.38 back from the inlets or 3.87 from the front of the wing where it hits the fuse. Indeed a little forward of the spar.;)

RE: 3Dfoamy.com F-18 setup question
 

Thanks vicman,
too windy to fly here today
I've moved the CG a little but, remounted the antenna an dI will try again tomorrow hopefully.
I plan on trying the 5.3 gears also.

RE: 3Dfoamy.com F-18 setup question
 

It was hard to tell did you have the prop going the right direction? If so you should have TONS of thrust.

I was able to get all the radio and flight gear installed last night here is how it looks.

RE: 3Dfoamy.com F-18 setup question
 

No, I think my prop has been on backwards, the side of the prop (GWS slowflyer) with the prop size printed on it was
facing away from the motor, unlike the pictures you posted.

RE: 3Dfoamy.com F-18 setup question
 

I think you just solved all your problems.:D Your plane will want to jump out of your hand now.[sm=bananahead.gif] I have my stabilator throw set to 50% and 15% expo to make it easy to fly. I went ahead and left my ailerons at 100% cause I like scaring myself.[8D] Have you watched any video of how it flies? When you land make sure the throttle is off, the prop will continue to spin in the air but will stop when you land without breaking. Also you want to let go of the elevator stick so you go back to neutral just before you touch the ground otherwise you will break the tips of the stabilator when they dig into the ground.

;)Your gonna love this thing!

RE: 3Dfoamy.com F-18 setup question
 

Wow , talk about feeling like an idiot !

This thing is awesome now. Now I just have to run out and get more batteries !

Thanks for all the help vicman.

RE: 3Dfoamy.com F-18 setup question
 

Are you going to tell us how it flies or keep us in suspense? I know it wanted to rip itself out of your hand this time.:D

RE: 3Dfoamy.com F-18 setup question
 

Yep, you're right. This thing is awesome now, it will go vertical.
It is also much smoother now that I have moved the CG back a little more.
Now it flies like I had hoped it would.

Thanks for all the help.

RE: 3Dfoamy.com F-18 setup question
 

Now get some paint on that thing.

Warning don't have an open paint container near alcoholic beverages and an unpainted model! Your plane won't respect you in the morning. I am a self proclaimed professional alcoholic beverage handler and this happened to me.[sm=stupid.gif][sm=spinnyeyes.gif]

mental note: gotta keep the foam away from that stuff too[sm=stupid.gif]