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Feb 16, 2019, 05:48 PM
Old newb
Thread OP
Quote:
Originally Posted by Spaaro
Good precautions, r39o..."Live Long and Slope Prosperously"!

I finally touched my FX-706 for the first time today since Christmas!
I have been reading your build thread & a few others--to 'psyche' myself BACK up for the process.

I never imagined setting up pivot tube bearings would require as much forethought, but watching someone else do it reveals a lot.

I'm back in San Diego come Sunday and will be watching the skies if they're not wet.
Going to rain on Sunday, they say!

Was hoping to get out, but I doubt it now.....will be out of town next week....sigh....

I really want to try my DreamFlight Libelle I just rehabbed.
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Feb 16, 2019, 05:56 PM
Old newb
Thread OP
Assembling the center section.

My ongoing quest for cheap flying leads me to the 99 Cent Store for epoxy and waxed paper so things do not stick on the table!

Everybody should have a few of the epoxies handy, but, as I found out, like Super Glue, do NOT keep it more than a year or so.....

Ask me why I had to open a second package or epoxy......

The cut off tubes need a spacer which is just a scrap of wood (Starbucks stir stick?) epoxied too.

Keep it all nicely aligned on the flat surface. (it is drying as I type....)

I will cut with a razor saw (which I bought cheap somewhere but can be expensive (Hobby Lobby) for the exact same thing!)

Next will be the steel shaft, magnets and control horns (as soon as I find where I hid my stash!)
Feb 17, 2019, 04:33 PM
Registered User
A little more progress

Do i glue it all up or leave the ability to take apart again?
Feb 17, 2019, 09:37 PM
Old newb
Thread OP
I stuck my wing roots in today. No glue. BUT but but, I think a couple of dabs of hot melt, E6000 or something along the bottom of the root "may" be a good idea, maybe. Do not know, yet. The roots are a tight fit as they are.

I am getting my steel wing rod ready.

I am about to dig out my hardware junk box to get out some control horns.

I am thinking of control horns right on the spar.

Servos between the leading edge of the wing and behind the canopy. That way the servo wires go straight to the receiver. I can use bigger servos too. Just my current ideas.
Feb 17, 2019, 10:40 PM
Registered User
I used one drop of glue to hold the servos to the center section.
Their fit in the fuse is tight enough
Feb 18, 2019, 12:18 AM
Registered User
The root sections are friction fit but the joiner tube has to glued.
Used some balsa wedges to center it ,when dry will trim flush
Feb 18, 2019, 12:21 AM
Registered User
Test fit the wings to determine tube location.

Balance and set up radio and thats about it.
I did not note the cg position but will use online
Cg calc to get super close.
Feb 18, 2019, 10:23 AM
Old newb
Thread OP
Quote:
Originally Posted by steeg
Balance.......
I did not note the cg position but will use online
Cg calc to get super close.
See post #11 at the beginning of this thread for CG......
Feb 19, 2019, 02:06 PM
Registered User
All done
With just battery and rx balances at 2.5 inches
And weighs 200 grams. Toss test in the alley
Went well.
Will use tape to cover tube area a quick sand to remove pimples.
Cant wait to test on slope!
Feb 19, 2019, 02:35 PM
Registered User
When gluing the tubes into the wings take special care with the alignment. I ended up with a tiny bit of anhedral.
Feb 23, 2019, 11:14 AM
Registered User
Tossed it off a slope yeaterday in 5 or 6 mph and it was a very poor slope but this little plane stayed up.
Joiner tube got loosed so wings flopped arou d a little bit bit kept flying anyway.
What a fun plane!
Feb 23, 2019, 02:14 PM
Old newb
Thread OP
Quote:
Originally Posted by steeg
Tossed it off a slope yeaterday in 5 or 6 mph and it was a very poor slope but this little plane stayed up.
Joiner tube got loosed so wings flopped arou d a little bit bit kept flying anyway.
What a fun plane!
Pictures or it ain't real!
Feb 27, 2019, 04:58 PM
Registered User
Flew off a proper slope yesterday and am surprised at the speed range of this plane.
Everything was fine until i tried to roll.
Those magnets are not a strong enough
Retention system for these wings!
Feb 27, 2019, 05:13 PM
Old newb
Thread OP
Quote:
Originally Posted by steeg
Those magnets are not a strong enough
Hey it is an experiment!

Depends on your choice of magnets, position, and the metal rod.

BUT, I too think a different system may be needed.

Something with tension between the roots of the wings at the pivot.

Rubber band or a spring. Or some other elastomer like sewing elastic.

That gap under the pivot through the fuselage may be big enough.

I was also thinking of something more mechanical, but it is complicated, and I have not pictures to show it.

So maybe just a rubber band pulling the wings together under the pivot tube may do it....

I will look at yours when I am in OC in the next days.
Last edited by r39o; Mar 08, 2019 at 12:55 AM.
Feb 28, 2019, 12:19 AM
Registered User
I really enjoy my FX707 pitcheron in light wind and thermals. The cambered wing sections, aspect ratio, and fairly low weight (150g all up for me) make this plane a joy to fly in light air. With a bit of ballast she can handle some breeze too, but above 15mph I like the Lidl glider with stubbier wings better.

Some notes on my build:
- Pitcheron: I glued small 3x2mm carbon tubes to the leading edge to hold a push rod (1.2mm wire), and mounted small servos below the LE. At the horn, the pushrods are connected with a simple outward facing L-bend. The tubes only allow the pushrod to rotate in one plane, which turns the pushrods into springs that also retain the wing. The wings can be easily removed by bending the servo horn a bit outward & pulling the pushrod. The pushrod folds next to the wing, so nothing sticks out for transport.
- I stripped two servos (one plastic micro, one metal gear) until I added a bend in the pushrod to absorb shocks in crashes. In really hard crashes the pushrods now bend a little, but it is easy enough to bend it back. Can also be used for fine adjustment.
- On the FX707 I use a 4mm solid carbon rod (4x3mm tube and solid 3mm glued in with thin CA) for the wing joiner. I think this is pretty much the thinnest you can go, I did break quite a few 4mm tubes. The flex when pulling out of a hard dive is pretty extreme with this setup. If I were to do this again, I would use a solid 5mm rod as the connector, and a 7x5mm tube in the wing. Those dimensions work very well in my Lidl glider.


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