E20 with capacitors

[bentodd]

I first saw this in Free Flight Quarterly, an E20 size plane using a capacitor as the power source.  I wanted something easy so I made mine with Depron.  I loosely scaled a E202 super Pearl down to 20 inch wingspan.  Ordered some 10 F capacitors and small drone motors with props from Amazon.  Added some camber to the wing with a hair drier as much for lift as to add some stiffness.

Flew it for the first time today. I charge the capacitor with a single cell lipo for about 15 seconds.   It was easy to trim since the capacitor has 2 or 3 seconds of full power and then slowly drains down over another 20 seconds.  There is no dramatic transition needed.  Mine flew left-left.  I used a binder clip to hold the pylon on so I could adjust it.

Once I got it trimmed, a launch at 70 deg with authority would give me 30 or 40 feet of altitude and total time of +30 seconds.  Nice for a small park.  Definitely fun.

Next will be a stick and tissue model.

[OZPAF]

Scaling down a existing FF model was a good idea. I have built a 16"WS model in depron with a 720 coreless motor, 65 dia prop and 15F SC. I used a cheap buck voltage circuit from Banggood to charge it to 3.5V which provided 45-60 secs flight time.

I would suggest you upgrade to a 15F and charge to 3.5V. I  think you will be surprised at the extra performance.

John

[cvasecuk]

Here is my "Diddie Dixie". It is 20" span and weighs 25g. I charge the 10F capacitor to 4v and set the viscous timer to about 60s. If I didn't have that I would have lost it several times! It is a super 'fun' model. Charge it, chuck it and chase it!
Ron

[Invader3]

That's really neat, Ron !
I've been thinking of a capacitor powered fun flyer and this looks a great way to go. Any recommendations for motor/prop and where to source?

many thanks,
John

[cvasecuk]

The motor is a Racerstar 8520  53500RPM Coreless Motor, the prop is standard 65mm, and the capacitor is a SUPER CAPACITOR 10F 2.7V RADIAL.
Just use e-bay for the best price, I think the motors and props came from China. 4 motors were £12, 4 capacitors were £10 and 20 props (10 CW 10CCW) were £6. That was 2 years ago.
I used a small switch between the capacitor and motor.
Ron

[glidermaster]

That looks great Ron, I love it, one of the nicest little models so far. Please consider uploading a plan!

Just a thought though, might 'Pixielander' be a better name?

John

[cvasecuk]

To get the plan just take a full size Dixielander and print it at 40%.
That is what I did!
Ron

[OZPAF]

I have built a 16"WS model in depron with a 720 coreless motor, 65 dia prop and 15F SC

Whoops! I used a 10F in this model which weighed 20g and flew very well, even though it's not as light as I would have hoped.

I think Ron's approach is spot on for SC models.

John

[Invader3]

Many thanks for the info, Ron - and I've already downloaded the plan ready to reduce!

John

[Yak 52]

Here is my "Diddie Dixie"...

I like it! 

Undercambered section?

[cvasecuk]

Jon, The model is a 40% version of the Dixielander, obviously wood sizes are 50%, and if the wing section was good enough for George it is good enough for me! Here is my rib template!
Ron

[airplay]

Hi, the 8520/10F combo? How many seconds i dead air?
Jens

[fred]

A Geared 8020 motor on a 10F cap gives longer useable duration than as a direct drive setup. 
Care in overvolting  caps as that is the traditional technique to explode them.

[cvasecuk]

My flights are usually at least 45s and are often more than 60s but who knows what "dead air" times are!
Ron

[Styx]

What motors are you all using in your E20 models?