Today was not a good day to fly...

Today was not a good day to maiden a 12 oz 3D foamie. The good news: foam floats. The bad news: water is wet. Lipos hate being wet. Sitting here looking out over the treetops, the winds aloft are 10 to 15, gusting to 20 and more. Almost dead calm at street level. Third observation: foam doesn't fly. It just holds the motor to the control surfaces.

Bummer. New motor; and I liked it, too. It turned a 12x6 at 5500 rpm on the bench last night. Time to quit sulking and find that WD40...

Reply to
Boat
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I put my little AXI outrunner in the lake the other day (it flies a Piper Cub on floats). Didn't come to any harm... neither did the 2 servos that got wet either.

-- Philip Rawson

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Reply to
Philip Rawson

Any special post-flight procedures, or just "hang it out to dry"???

Reply to
Don Parker

I just worked up the nerve to put a meter across the battery pack. It defies logic, but I'm not complaining. It still has a full charge after being submerged for 20 minutes. I'll let the esc and rx dry a bit more before probing them for life. Hope springs anew. The servos will just have to fend for themselves. Unless someone knows a painless way to free them of their tape.

I'm now of the opinion that 3d foamies torque roll so well because they leave off all nonessentials. Such as wings. Modeling a flat plate lightweight in G2, stalls are harsh with no preamble whatsoever. I didn't manage to land safely even once in an hour of trying, even in dead calm. Should've would've could've tried this before springing for the impulse buy. People really fly these things?

Reply to
Boat

Yep, a 30mph gust slapped me out of the sky yesterday, and into a tree the night before. Always good for a laugh, but I better get taping 'cuz I've run out of things that are flyable.

Reply to
Steve Banks

I hung the airframe up to dry in a not too warm place. Of course I had already run up the motor which would of got most of the wetness out...

-- Philip Rawson

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Reply to
Philip Rawson

Fresh water doesn't have the low resistance that people think it has... some current will of flowed while your battery was submerged, but not enough to kill it.

Just leave the servos in a dry warm place... you can't get to the important bit anyway (the pot), even if you took them apart.

I bought a second hand TV. Someone had spilled something very sticky and slimy in the remote control, I took it to bits and scrubbed it in water and detergent. The only bit I was careful with was the rubber switch contacts. A few minutes on a radiator and it was working fine and a lot less sticky...

-- Philip Rawson

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Reply to
Philip Rawson

Not at all. Fresh watee is an insulator at the sorts of currents ad voltages we are discussing. The avionics will have been drawing far morte, and they can not flatten a LIPO pack in 24 hours.

Put all the electronics in a warm dry place - clothes cupboard for AT LEAST 24 hours.

Tset each comnenet seprarely. If e.g. the ESC BEC has broken, you could fry everything else, but hey, it survived soo far, so its looking good.

Dpusng in alcohol is not a bad way to get water out of things - it mixes with the water and runs off, and leaves just a bit of damp alcohol that evaporates quicker. It will also take oil out of anything so be sane.

Isopropyl is good (screen cleaner etc).

CG too far back. Makes em twitchy. Star furtheer forward and go back when you have the hang of it.

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Reply to
The Natural Philosopher

A lot of UK water is high in minerals which conduct a fair amount o current. Nothing compared to a motor though!

Reply to
Paul McIntosh

Since getting into RC flying, I've discovered the little known FACT that trees attract syrafoam. Get within fifty feet and the effect starts to be noticable!

Cheers'n Beers.. [_]) Don

Reply to
Don Parker

But u left out part of the equation: The strength of the attraction, which is directly proportional to one's age and the height of the center of attractive force of the tree :-(

Reply to
Dan Wenz

| Third observation: foam doesn't fly. It just holds the motor to the | control surfaces.

Foam flies fine. What you've described has happened since long before people started making planes out of foam. As the engine/motor gets bigger and bigger, the importance of the wing goes down. Eventually, the purpose of the control surfaces and wings becomes simply something to point the engine in the right direction. :)

There's lots of gliders out there made of foam with no motor at all that fly just fine ...

Somebody else commented about flat wings, and how he modeled it in RFG2. To be fair, I wouldn't trust RFG2's for a task like that -- it's flight models are a bit simplistic (which is ok for normal flying, but once you start looking at stalls and spins and such, it starts to fall apart.) X-Plane might be better.

| Bummer. New motor; and I liked it, too. It turned a 12x6 at 5500 rpm on the | bench last night. Time to quit sulking and find that WD40...

Your motor (and plane) are probably just fine ...

Reply to
Doug McLaren

To be fair, properly shaped airfoils fly fine almost without regard to material. Foam is a wonderful material for cutting or shaping airfoils. I had in mind flat foam wings. Little lift, no washout, full length ailerons, and high alpha. Sounds like a recipe for mishap, but I'm no ace pilot.

I learned in G2 belatedly that they can indeed be flown by keeping elevator inputs much softer and smaller than I'm used to. Simplistic it might be, it still reproduced yesterday's unintended water landing suitably well enough to determine the true cause: Pilot failure. Gentle elevator would have brought it home.

They are, much to my surprise and joy. The only part that failed was an amplified y-cable. The sneaky guy at the hobbyshop put in my shopping basket on my behalf; $17 and 1 oz of unnecessary failure point. I replaced it easily with a few grams of solder and shrink tube.

The treetops are showing 5 to 10 kts... at ground level, occasional puffs to less than 5 kts. They don't get much prettier. I'm going flying...

Reply to
Boat

Recap: It flies. In fact, it flies very nicely with very mild manners, and transitioned easily into a hover and stable torque roll with no drama at all. What a difference a day makes.

E-Flite Tribute, 3s1p 700 mAh, E-Flite Park 370 4100 Kv, 6.6:1, 12x6. The motor wasn't even warm after 5 minutes of slow flight and high alpha. The pack (the one I gave up on as having been drowned) still shows an almost full charge with 11.3 V.

I ended the flight early because the fuselage spar torqued itself lose from the surrounding foam at the nose. The motor and gearbox mount to the end of the 1/8" round carbon tube. All that resists the motor torque is the CA that holds it to the foam. The CA held, but the foam didn't. A small scrap of

1/16 ply for reinforcement will fix that.

I can't tell you adequately the skepticism I held as I glued up the flimsy foam. Yesterday proved the rightness of my trepidation. Today dispels it permanently.

Reply to
Boat

did you mean kites or kits? crowded airspace?

Reply to
The Natural Philosopher

The word "kite" came to mind in yesterday's stronger wind. Even tethered, it would have been a problem. No airspace problems here. The little league diamond outside my back gate is empty from September until early May. Even the geese will leave us soon, and then I'll have it all to myself. Pretty much. Just the one or two neighbors who use it to practice chip shots.

Reply to
Boat

kts = knots. Light winds. Good flying conditions for unaerodynamic lightweights.

Reply to
Boat

Ah. Never seen knots abreviated before.

Reply to
The Natural Philosopher

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