Projects New Foamie Build

Stambo

Well-Known Member
After crashing my wing a while back, long story short, wrong model selected on tx, I have been looking for a smallish high performance pusher to put the electronics on.
I was never happy with the tail waggle that seems inherent on most wings so I won't build another.
This will be for proximity FPV so has to have room for stuff inside.
I haven't been able to find plans that I am happy with so I decided to make my own.
I have started with a cardboard mock up to get things looking right and figure out what I need to do to get the CG right.
Wing span is 750mm, power from a 2700kv 2205 DYS quad motor with a 6045 prop.
Might even stick a Naze in there for some stabilization.
I have a choice between 3s 850, or maybe 2 parallel, or a 3s 1800, as that is what I already have.
Depends how the CG works out.
Gonna make the control surfaces a bit bigger and use a KFM airfoil for the wing but beyond that it should be pretty much as you see it.
Any other suggestions are welcome.

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Tony

Staff member
Looking good, and you are right about the tail wiggle on the wings.

Question, why go with KFM and not a standard airfoil? I know KFM is way easier to build, but you are just as strong and lighter with a standard air foil. The next RCH Trainer design is going to be a traditional airfoil. Just asking.
 

Stambo

Well-Known Member
Question, why go with KFM and not a standard airfoil? I know KFM is way easier to build, but you are just as strong and lighter with a standard air foil. The next RCH Trainer design is going to be a traditional airfoil. Just asking.
Exactly that, easy to build, especially with the wing shape, although I could still change my mind.
I was looking at the flight test style wing, I could straighten the front edge to make that easier to build, just don't think it would look as good.
I dare say this will get crashed a few times so if it flies well I will probably build another that I can quickly transfer the electrics to in the event of a bad one.
I would love access to the $1 foamboard you guys can get, ours costs NZ $15 . :)
Still a cheap plane as it should only need one sheet.
 

Tony

Staff member
If you have decent paper on your foamboard it is likely better stuff than that $1 a sheet stuff we can get. Although it would also be heavier. If this does good for you, and you don't mind, send me the drawings or whatever you made and I can turn them into some PDF plans for the site. I had a bi-plane but since that member left, I removed it. And I need to get some more planes on here for people to build and have fun with without breaking the bank. I need to work on the trainer as well though lol.
 

Stambo

Well-Known Member
At the moment there is no drawings, it is all in my head.
Once it is finished and I am happy with it I will take some measurements.
I might even have a play in sketchup or something similar.
 

Stambo

Well-Known Member
Ok the air frame is built, just gotta cut in the ailerons and a hatch for battery and stuff and it's ready for some electronics.
I sat them in place and I am a bit worried that it may be a bit tail heavy, even with the 3s 1800 up front.
A flight controller will compensate for that to a degree, make it controllable until I can figure out exactly where the CG should be.
Yes, I will be fitting a flight controller, just for stabilization so I can fly more comfortably in the winds we get around here.
The last thing I want is to be flying low through a gap and get hit by a gust that sends me into the ground or a tree.
In case anyone wants to know, the square pieces of wood are paulownia, almost as light as balsa but quite a bit stronger (I hope).
It is commonly used in light aircraft construction.
I'll post more pics when it's ready to fly.

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Tony

Staff member
Another thing you can do if you have the space to combat the tail heavy issue is put a 2200 up there. Slightly heavier. And on small planes, some kind of stability is nice to have. I would not think about flying my Habu without a gyro on it. I think it has the AS3X, it is a blade model afterall. But been crashed too many times now and doesn't like to fly that well anymore.
 

Stambo

Well-Known Member
I got this thing flying on the weekend, had to go down to a 5" prop as the motor and ESC got a bit hot and the ESC reduced power.
I will also have to put some air flow through the fuselage to cool things down a bit.
I was unsure if that motor would handle a 6" prop, now I know, with a 5040 it was just warm so I am going to try a 5045.
The flights went ok but it was to windy to try anything too radical.
As suspected it is a little tail heavy and the biggest battery I have that will fit is already in there.
Would love to try a bigger motor but that will just worsen the CG issues.
The flight controller made it flyable but it needs a bit of tuning, I will wait for a less windy day before I try pass through mode to see how it is without stabilisation.
Unfortunately the battery in my Mobius seems to have died and the other camera batteries were flat so no video.
Next flight I will have an FPV cam up front so I can record from my goggles. That might help a little with CG also.
I find it far easier to throw a plane around with the goggles on so I am looking forward to the first FPV flights.
 

D.O.G.

Goblin 380 Supporter
That's cool Stambo. I made one too from dollar general readie board. I haven't try to fly it yet because I dont have room here at the house but I'll make it to the park to try it out. I have no idea what will happen if it's tail heavy or off COG but I'll find out. 16956-f738c532615c32cfbf5d56fe7da3e81b.jpg
 

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Stambo

Well-Known Member
Hopefully after work today should be good for a flight or three according to our forecast.
The Mobius seems to be taking some charge now so I might be able to get that on there.
I will have to dig out and charge another camera so I can get some LOS video too.
 
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