SE-5a Scratch Build

[synjin]

So, I printed the plans and built the FT Mighty Mini SE-5a. When it was done I decided to paint it before flying it (we'd had a bunch of snow). Now I'm off to maiden crash...I mean maiden flight it. It may not look this good in an hour. I'm trying a 2206 1400Kv motor with an 8" slow fly prop. We'll see how it works.

 

[FastCrash45]

So, I printed the plans and built the FT Mighty Mini SE-5a. When it was done I decided to paint it before flying it (we'd had a bunch of snow). Now I'm off to maiden crash...I mean maiden flight it. It may not look this good in an hour. I'm trying a 2206 1400Kv motor with an 8" slowly prop. We'll see how it works. View attachment 125550

Excellent job of putting that together and NICE paint job. Your maiden will be good no worries, right?😎

 

[synjin]

Tail heavy. Fortunately, I only got about 5' off the ground, did a couple of cartwheels, etc. Had to re-glue the tail skid and one of the landing strut covers. I added 2 1/4 oz of weight to the front for better balance and will try again tomorrow.

 

[Gazoo]

Sure is a nice looking build.

 

[FDS]

Balance point is on the top wing, at the bit where the profile changes.
You could try a heavier battery instead, carrying ballast when you could carry extra “fuel” never seems logical to me. I run an 850mah 3s in mine. You can also move the power pod further forward to counter act the tail weight.
The SE5 can be a handful, I found mine flies much better at lower throttle, more scale speeds. It tends to end up hanging off the prop otherwise. The landing strut covers on mine were in 3 pieces within two flights. The wire gear flexes and they stay rigid, leading the foam core to shatter, then the paper rips.
Nice paint job!

 

[synjin]

Well, it flew...about 100 feet, did a wing over and landed nose first on an icy parking lot. “Curse you, Red Baron!” At the very least it will need new wings. I also need to figure out why it’s so tail heavy. I’d rather not scrap the fuselage, but to get it to balance I had to put 3.75 ounces of weight in the front as well as a 3S 850maH battery.

On the upside, the motor and prop combination put out a lot of power. If I had had a steadier hand I probably could’ve hung it from the prop. I think I’ll pull the power pod and use it in the Dornier Libelle that’s started on the work table. After that it’s either the DR-1 or the Mini Sportster before I get back to the SE-5.

Fortunately, this was all foam core. I would’ve been very demoralized if it had been a balsa plane. Ah, the things you can do with a couple of sheets of foam core.

 

[FDS]

What board were you using? The FT board has a very light foam core. Here in the UK there’s no equivalent type, so it’s FT board or alter the plans. The tail heavy problem is exactly what happens when the board used is too heavy, since FT designs usually have exaggerated tails.
With the minis light weight is everything, there isn’t much room for error. Any added weight and they become much harder to fly.
The solution is either to use FT board or go down a thickness of other, more dense board and adjust the plans as you cut, it’s only the fold areas that are different.
Sorry to hear your valiant SE5 was lost to ground fire on its first flight. Get the riggers to to work on repairs then try again. Mine was made from a speedbuild kit and it nearly slammed into the ground the first flight, I kept it up more by luck than judgement.

 

[synjin]

I used Pacon foam board, as I can't get Ready Board locally and the only other foam core available is Elmer's Foam Board which is very dense. The Pacon is very light compared to the Elmer's but I'll have to weigh some Pacon and FT foam board to see how close they are. I was thinking of redoing the SE-5 and adding about 1/2 inch to the front to give more room for balance. Not sure how much that would mess with the CG. I'll probably have to watch that with the Mini Sportster as well (have all the pieces cut out and ready to glue).

That motor though, wow! It's a Gartt 2206 1400Kv. With the 3S battery and 8 in. slowfly prop it put out a LOT of power!

Ah well, c'est la guerre.

 

[FDS]

Wing loading will be your problem with more mass. The CG will be fixed but you will still be heavy. FT board is the best for minis in my experience.
I run a 2206 2400 in all my minis, they work on 2 or 3s. I found mine flew best with that motor on less than half throttle, I tried a 5x3 with it, the sound was wonderful but it was less efficient. I might try a 6x3 with it. My son has the EU power pack F by Graupner on his DR1 and the motor is amazing, that thing is so efficient, you can get 15 mins out of an 850mah 3s.
You could hang the motor further out front too, that might help.

 

[synjin]

This was the aftermath.

 

[FDS]

I did a similar thing to mine trying to fly it inverted. Except the left half of the bottom wing was ripped off!
That’s easily repairable. Put cocktail sticks across the snapped struts, fix them with white gorilla glue. Cut out one new end strut, that one is dead! You can heat the glue to remove the old one from the wing, use a hairdryer.
If you put the motor so it’s rotor is clear of the fuselage that will give you a lot more forward weight distribution, especially if you hang the battery on the end too.