Conference vmszoo::rc

Hi Dave. There were several Fun Ones built by CMRCM/DECRCM people a few years
back. I think there was a deal on them a few WRAMs shows ago. I think Dan Snow
and Charlie Watt both built them and I think at least Charlie put a .32 into
his. I have three of those .32s and they are the nicest engine to use. The dual
needle carb is a pleasure to use and the power to weight is incredible. I think
it would be a great combo. As for the flaperon issue, if you split them, put in
4 servos and fully mix them. Seeing Eric's Goblin in crow mode (flaps down
ailerons both up) stop in mid-air was impressive. You can also still get full
span ailerons this way with mixing (at least with the 347 I can) I thought
there was a fun-one topic but it must have been in the DECRCM file since that
was back in the days where there was a rift between groups.

    
    	Hi Dave,
    
    	I'd also go with the OS32F, this is a dream of an engine.
    	No problems with mine, and others that I know of. 
    	It's well worth the extra money.
    
    	Also go with a tail-dragger, you'll have more fun and
    	they look nicer!
    
    	Brian
    

Another thing I thought of after I entered my note is that this engine is also
the basis for one of the best helicopter engines. This speaks very well on it's
reliable idle and good performance.

    Rift? We don't need no steenking rifts!

    I had searched for "fun" and "one" and didn't pick up a Fun One
    thread (kinda surprised me a bit) hence a new thread was born.
    Perhaps it's lurking in a different note?

    Looks like the engine issue is pretty clear then. I'll have to see if
    RC Buyers can come close to matching Towers price @ $135 (ouchie!)...

    I'll have to dig into the 8UA manual to see how to mix a 4-servo
    TE. I know it can do "crow" mix in the glider profile, but I didn't
    take much notice on how to do it with the "acro" mode...

    Assuming it can be done, is there such a thing as a light/fast/cheap
    Futaba servo? (or is this one of those "pick any two" deals? ;^) I
    don't think I want to encrust the wing with 4 S148's and take the weight
    hit if I can avoid it without taking out a mortgage to pay for this
    bird...

    As for the trike vs taildragger, I'm still torn on that. While 
    I've setup the US60 and the EZSport as taildraggers, I'm still
    wondering if a trike would make more sense for a fun fly machine.
    Yes, I know it'll look nicer as a taildragger, but for the intended
    use, which setup makes more sense?
    
    Thanks for the feedback so far!
    
    /dave

    /dave

    

You may have to roll your own on the acro mixing. If it will do full camber
changing and crow controlled by a switch, it might be easier to convince the
"spoiler" stick to be a throttle 8^) Don't let a manufacturer's
classification make you avoid using a different mode if it's a closer match.

I used Futaba 9601 servos. Don't know what the latest model number is.
They're coreless and fast and weigh 1.1oz each so they're a nice compromise
over the 1.6oz 148s. Cheap?? well, 2 out of three ain't bad 8^)

I think for touch and go manuevers and such a taildragger works well. I think
the nose gear can be more of a bother since you're not typically "greasing" a
fun-fly touch and go. Loop and gos are more like a pancake and a taildragger
is in the right attitude there. This is really more of a personal preference

I looked in the vmszoo::decrcm conference that's set no-write and didn't find
the notes I was thinking of. It's probably buried in another topic.

I built a Fun One two years ago and flew it *hard* until I accideltly 
snap-rolled it into a tree ...

Here's my take on your questions:

Engine: I used my trusty OS 46 SF and it had terrific vertical.  Don't use a 
wimpy engine on this plane or you will limit the "fun" potential.  Go for at 
least 1.2 HP rated engines.

Trike vs. Tail dragger:  The stock landing gear used in tail dragger mode 
made for a *very* bouncy landing plane.  I disliked this very much, cause no 
matter how slow I tried to land, it always bounced and was sloppy in rollout. 
Other club menbers who had tail draggers had the same experience, whereas 
those who built trikes had much better landing performance.  Use trike.

Construction:  You're right, tank space is at a premium, so squeezing in a 6 
oz tank required a little playing around with the engine mounting 
arrangement, but it can be done.  Also, the firewall, as I recollect, was 
glued in such that it didn't look very strong, so I added triangle stock 
behind it, and used some thin dowels to secure it to the fuse sides.  
Fiberglass all around wouldn't be a bad idea as well.

Flaperons:  I built mine with one servo per aileron, and used programmable 
mixing to get flaps, spoiners and elevator/flap coupling.  Just about all 
this worked out well except that I found the elevator flap mixing caused a 
severe adverse yaw problem at low speed (almost lost it a few times on final) 
so ultimately I stopped using this except at high speed when doing tight 
loops.  

But I loved the way this plane performed snap rolls and tumbling maneuvers 
and how it was a ball to fly in high winds.  It's not for the faint of heart, 
but once you have a low wing trainer under your belt, this is a good third or 
fourth plane to wring out.  

-Joe

    Thanks Joe for the input.
    
    I've gotten the fuse nearly complete - just need to tack on the tail
    feathers. I didn't like the looks of a few wing pieces in the kit
    (the preformed/notched TE pair had cracks running completely through
    one of the pair, two of the spars were warped *and* twisted, and one of
    the ailerons had a major bow in the hard-to-fix direction (edge-wise),
    so I'm waiting on those before throwing the wing together. I got about
    two nights worth of things to do before I'll be idled waiting on the
    wing bits...
    
    I managed to shoehorn the 6oz tank in its little home, and still get
    enough latex padding around it to keep the foaming down. I also
    reinforced all nose joints with triangle stock - and put the entire nose
    together including the triangle stock in one shot with 30 min epoxy
    I figure this is the best way to make the whole works as solid as it'll
    get). I might drill in a pair of dowels on both sides as well if I get 
    the urge...
    
    I did go with the OS32F - RC Buyers matched Towers price. A sweet
    engine with the good carb. Puts out 1.02HP but only weighs  ~250 grams
    - for a major weight savings on the nose over most 40's and certainly
    over a 46. I'm trying to balance the power vs nose-weight to avoid 
    adding even more weight to counter that problem...
    
    I'll be using 3" lite tires which will save another good chunk of
    weight up front -  and perhaps will cut down on the bouncy
    landings/rollouts - over the  stock GP rubber. 
    
    I'm not wild about the aluminum gear either - but actually it ought to
    be less bouncy than piano wire - the aluminum is so wimpy it will deform
    way before wire would ;^) sorta like single-usage shock absorbers.
    We'll see - if it's really a problem reconfiguring to a trike isn't
    much of an effort...
    
    I've also sprung for the 3101 servos, but I'm going to go nuts and use
    four of them on the wings (hey - it's the last new-build of the season!
    why not? ;^) The set of four is still much lighter than a pair of
    S148s! Gives me a chance to play with separate ailerons/flaps and all
    the doo-dahs you can get out of those (just think - a multitude of
    "Crash Modes" to misuse!)
    
    So far I've taught my tx how to do crow/butterfly via a toggle, as well 
    as the straight flaps and elevator/flap coupling, etc. Next tricks are 
    to see if I can couple the ailerons to the flaps to increase the roll 
    rate, and/or to couple the crow mode to the throttle stick 
    (automagic dive brakes?) - with a toggle to disable it, of course. The 
    latter I'm almost certain I can do; the former might not be do-able 
    without an add-on mixer...
    
    This has actually been one of the more fun kits to build over the 5
    other birds I've put together this off-season. A lot more
    plotting/planning than the others - which other than a minor decision
    here or tweak there didn't stress the brain-pan much...
    
    Hopefully I won't use it to dig a post hole! ;^)
    
    /dave 

    I have flown two Fun Ones built by my students flyers.  Both has OS40
    motors are are over powered.  The OS 32 engine would be perfect.
    A tail dragger idea is truely better.  This plane flies like an
    angel and lands slowly.  You will love it.
    

    Took my Fun-One down to the CMRCM field Sunday afternoon. Figured if I
    couldn't find someone qualified to give her a good going-over and a
    test-hop or two I'd practice taxiing around and take-off run-ups.
    The OS32F/abc was bench-broken and rarin' to go, but I didn't have the
    nerve to solo it...
    
    After putting in a bunch of flights with our trainer with about 20
    touch'n'go's, and watching the few other flyers getting some stick
    time, I fired up the Fun-One and commensed ground manuevers. After
    getting reasonably comfortable with the tail dragger, tooling around
    the field and just breaking contact on near-takeoff runs, I succumbed
    to the peanut gallery's badgering to get the plane in the air. 
    
    Wheeeee Doggies! Other than a pretty enough takeoff, it was all
    white-knuckle time until the I finally managed to get the elevator trim
    squared away. I learned at least one lesson: don't use high rates on
    the first flight! Actually, I learned a second lesson as well: don't
    take your eyes off the ship to look for the trim buttons! I did that
    twice, and nearly buried the ship at the end of the pits the first time,
    and was on a collision course with a tree the second time. Phew!
    
    OK - so I dialed in a bunch of up elevator, a couple of clicks of
    aileron, and got the sucker under control - just in time to run out of
    fuel *way* downwind (oops! forgot how long I had been taxiing around
    the field!). Thankfully I had plenty of altitude by that time, and was
    able to easily reach the field, smoothly touch down on the mains about
    mid-field - and then roll-out the rest of the field into the tall
    grass (did someone say "use more flare next time?")
    
    Not a mark on the plane. The insides of my knees are black and blue,
    however! ;^)
    
    Lesson number three: triple-check the CG before taking bird to field. I
    had set the CG before covering, and apparently when I reassembled
    everything I reversed the battery pack with the rx. Coupled with the
    chunk of tubing I added to the exhaust, the cg had moved forward about
    an inch in front of the recommended range...
    
    Ah well...I'll be ready for another go - with some knee pads ;^)
    
    As long as I'm here: Could someone turn down the wind machine for me?
    Flying in 20-30mph shifting crosswinds is getting to be annoying! I
    won't know what the heck to do if I ever get to the field and there's
    no stiff breeze blowing!
    
    /dave

    So, we decide to go fishing on Saturday, and flying on Sunday. Guess
    which day brought plenty of shifting wind?
    
    I straightened out the CG on the Fun-One, took it to the CMRCM field,
    and got Steve Smith to lay his magic hands on it. After an engine tune
    up to get the idle down a bit and remove mid-range hesitation, and then
    cranking down the aileron rate a bunch, Steve had it doing all kinds of
    tricks (it was fun to watch the master at play ;^) and I'm now able to
    fly it without knee-knock syndrome setting in (yay!)
    
    Even with the gusty wind it tracks pretty nicely in the air. I'm still
    having some "interesting" experiences with ground handling though
    (managed  to trim the far end of the pit row barrier grass on one
    takeoff - *that* woke everyone up! ;^) but I'm getting better. Got
    through a full afternoon of flying without using up anything but glow
    fuel, and had a good time doing it...
    
    Definitely gotta do something about the aluminum struts, as they came
    shipped with *major camber* and negative caster - I gotta believe that
    ain't helping the ground handling. I'm going to take the mains off an
    give them the benchvise treatment to get the wheels vertical and
    toed-in a tad, then see how she does. On the upside, the mains and the
    mounting treatment do seem to stand up to some solid landing thumpage
    without splaying or ripping loose...
    
    I tried playing with some of the bells 'n' whistles, like flaps and
    airbrakes, at moderate airspeed and with plenty of altitude for safety.
    I was surprised just how effective the flap surfaces are: a mere two
    clicks resulted in a fairly swift climb, and the airbrake sent it
    nearly vertical (gotta add more up aileron and mucho down elevator to get
    this to work right). Just getting the mixes to work as expected will
    probably take a couple of afternoons, but that's half the fun, right?
    
    /dave