Projects First Foamie Build

[someguyinsandy]

This is only my second post, so please don't be too hard on me! (thanks)

I have been working on a foamie build over the weekend. It is nealy complete, and scheduled to maiden this Tuesday weather permitting. I did not use any plans for this one. I just kind of sketched it out as I went. I am looking for any feedback on this, especially predictions of how it will (or won't) fly.

The wing is a KFm3, but I slanted it slightly front and rear. Span is 33.5", root chord is 7" with 5" at the tips.
Motor: e-Flite 370
ESC: e-Flite 20 Amp
Battery: 1.3 Amp 3 cell Li-Po - maybe a 2.2 if I find that it will carry it.

Additional details in the video below! Please let me know what you think TIA.

 

[Tony]

That looks really good for your first foamie. Just for future reference, the Kfm3 goes to 50% and 75% chord. You have it at 25% and 50%. With that being said, I like it a lot. If you want to see the airfoil on my trainer (Kfm3), you can download the plans from the store if you have not already. My new plane will have the Kfm2 on it just to play around.

As for how it will fly, set your CoG at 33% chord or 1/3 the way back and about 30º of control surface throws and it will do fine. The control surfaces are not large enough for 3D, but they will do just fine for normal flight. I think it will fly well, make sure to get it on video!

 

[someguyinsandy]

Yikes! 75 and 50 percent... I thought it looked a bit wierd Well, it's too late to fix that now - I'll just try not to destroy the motor and try again. I'll definately video the maiden. Thanks!

Steve in Sandy

- - - Updated - - -

After giving the "Well, it's too late to fix that now" a bit more thought I think I can patch in some additional foam board on each wing to get the KF proportions correct and then recover with clear tape... I'll put a fresh blade in the handle and get after it - Thanks for the heads up!

 

[Tony]

I think it will fly fine the way it is now. I would put some spars in there though to help hold the wing straight if you don't have them already. The thing with the Kfm airfoils is you can change them around and play with them. Kfm is just a theory and not a proven fact. That is the main reason I'm playing around with them lol.

 

[someguyinsandy]

It is settled then. I'll bring along some precut sections that can be quickly fitted at the field to fill in the wing, but maiden it as is. Who knows, right!

Thanks again Tony.

 

[Tony]

That sounds like a plan to me. Can't wait to see it.

Oh, and the rule of thumb is you want twice as much down angle in the motor as right angle. It looked like yours was the exact opposite.

 

[someguyinsandy]

There you go helping again... I have looked all over for that info. There is a lot of mumbo-bajumbo out there regarding thrust angle, but you boiled it down perfectly! Yet another lesson I will not forget. I'll stop by the Ace and pick up a hanful of thin washers for shims.

Thanks again!

 

[Tony]

lmao, I can't help it, the last name in my forum is "Help"

 

[someguyinsandy]

Here is my progress so far. If the weather holds, and I get some time at the field (training day) it is going up.


Let me know what you think!

Thanks, Steve in Sandy

 

[Tony]

That's looking good. The reason for the blinking light is because either you left your Tx on and unplugged the plane and plugged it back in, or your Rx lost power somehow.

On the elevator, go into your travel adjustment and lower it to keep that from binding on up elevator. Can't wait to see the maiden flight.

 

[someguyinsandy]

Is it possible that making and breaking the bettery connection can cause that. I ask because I soldered a proper Deans connector on my battery, but all I had to put on the ESC was one of the "fake" Deans. They don't fit that well and it takes a bit of fiddling to get them together.

 

[Tony]

Yeah, if the Rx initializes a bind then loses it or power, it will cause that.

 

[someguyinsandy]

Enough said about the fake Deans huh...

 

[Tony]

Yeah, if you watch RcModelReviews on youtube, he did a quick video on them. The silver spring will flatten out and cause them to lose connection. I have some cheap ones, but there are good cheap, and crap cheap. But I'm pretty sure I will stick to the true deans from now on with all of the issues I have had with the fake knockoff crap lol.

 

[someguyinsandy]

Agreed. Regarding the travel adjustment... This is programming in the 6i transmitter I am assuming. (why does that noob keep bugging me?) I can hear it from here!

- - - Updated - - -

I got it - pretty cool. I guess I should read the manual a bit more closely Heh!

 

[Tony]

I would never say that lol. Yes, I can't remember if it's end point adjustment or travel adjustment, but it's one of those two. You will want the menu with everything saying 100% and you will want to lower the elevator.

 

[someguyinsandy]

Well, blustery rainey weather this evening precluded me from getting the Foamie in the breeze. Wednesday evening is supposed to be clear and in the mid 70's so I'm hoping to do it then.

Steve in Sandy

 

[Tony]

Send that stuff SE to us lol. It was clear, hardly any wind at all and 106º today lmao. I would welcome some rain down here.

 

[someguyinsandy]

I would trade you but that heat is a killer.

Do you notice a differance piloting a heli when it is hot vs. cooler? I mean a differance like flying at sea level vs. 5000 feet? I know airliners need a longer roll to take off when it is hot in Phoenix as opposed to up here. I just wonder if you feel that in your controls of small planes and helis.

 

[Tony]

I have never really paid attention to how they fly lol. May have to start doing so.