Only one more bend, but dont forget I always use a KFm4 so its a lot of layers to cut, chamfer and glue accurately...
The jig idea is great, that will help a lot..so its worth building first...

It might be worth trying a single layer build as well.. much lighter and even more slow flying...although the one in the video is very slow as it is..

Oh, forgot about the KF airfoil. When I get around to building mine, it will be a flattie.

It will be interesting to get your opinion of a single layer version, vs your Nutball,
I hope you will like it..
Make sure you keep the angles at 110 and 135 as it does make a difference if they are much altered....

NOTE the previous two videos had me flying at 30% COG... thats measured from the nose back to the rear of the fuse and hinge line for the rudder... this is a rearward COG, because when you go inverted the plane will go nose up, rather than dropping the nose as is more usuall..
Its quite happy there, and good for hovering , the COG is flyable well back and forward on this design.. when its spot on you will get the most axial roll and no climb or drop when inverted

these are my floats .. made to be removable..held onto two strips of velcro under the wing
Using velcro its easy to set the step on the float position in relation to the models COG... on snow I had it in front of the COG then the model would sit at a high angle of attack when still, but would rock forward to a lesser angle under power.. which worked out fine..

I have a couple Capricorns, full size and 65%. I like them but the 65% wants to fly faster than I like for indoor flying.
I like the heart shaped W by Dave and think it will fly slower.
I have 6 mm depron and I wanted to build a kfm2 version with a fuselage profile/canopy.
I combined Dave's Heart shaped design with the kfm airfoil top section only 50% back and the Capricorn plus my touches and call it a Scorpio.
Here are early pictures of it. It isn't done so I can't comment on how it flies yet.
Two panels are 12" X 24" with the center panels 6" X 24" like the heart shaped one. My rudder hinge line is 1 1/2" behind the center fuse. I have big elevons and big rudder. The rudder and profile fuse stick down thru the center section 1 1/2" and I have a full length flat brace under the center like the Capricorn.
I glued my pontoons on permanently.
My question/problem is where do I put the CG? Do I measure from prop to rudder hinge line and put it 30% back? 28 3/8" so Cg at 8.5" ?
Or do I simply put it 30% of the 24" center section which would be 7.2" ?

My receiver and ESC will be under the flat panel. The battery will be either velcro'd on the bottom or inside a hatch. It depends on CG of course.
My servos will just be top mounted like on my two Caps.

More to come...

Danford1

Looking real good... whats your center panel length?.....

Here is a quick pic on COG..work it at 27 -30 % on the center panel length

note 30% is with the back end slightly heavy but it still flies ok.... 27-28 seems most correct ... 25% is nose heavy

re: the floats... when the power is on and the model rocks forward on the floats, there needs to be a positive angle of attack on the wing.. about 5 degrees is working for mine...

The thrustline is set at zero to the wing, so you get the motor pulling up, reducing the friction against the grass snow, or whatever...this makes the model slide along easier, and it will take off on its own

My center panel length is 24". So with 27-28% the Cg will be 6.48" to 6.72".
No problem. Now that I know that I can mock up the servos, receiver, ESC, battery etc and set Cg and finish the build.
My float rear edge or step is 6" from the front edge so the Cg will be 1/2" to 3/4" behind the step. I wonder how it will handle on water like that.
My full size Capricorn has the Cg on the step. It flies great from water.
I haven't tried the 65% Cap off water yet. It flies fine off of fake grass at the indoor soccer field I go to. The Cg is at the step or perhaps 3/8" behind it.
Both of the Caps don't have a positive angle of attack while on step. They scoot along quick and lift when I give them up elevator. The 65% Cap does use up a lot of space before it lifts off though. It never didn't want to lift off, it always does.



Danford1

The Scorpio flies Great !
I flew it 4 times on Tuesday. The maiden flight was outdoors just to see if it would fly with a 2S battery. It did no problem so I went to the indoor place.
It flew great. Much slower than my mini Cap. It was very stable and turned fine with either the elevons or rudder. Even flying very slow.
I have a couple videos I took. 1 is from a #11 camera on my hat. It just shows me flying around inside, kind of boring, but it flew fine. It was the first real flight other than less than a minute outdoor trial. The other video is an onboard camera looking rearward as I flew around in circles indoor.
I have the Cg between 27-28%. It is 6.65" from the front edge.
I had to mount the servos all the way forward and also mount the battery all the way forward.
I thought for a while about cutting off some of the huge rudder and elevaons but i was able to balance it so I'll leave them alone. I could have also extended the motor more forward.
I haven't tried inverted flight or any stunts yet. I'll do that outside where I have room. Indoors is tight for experimenting. I'm not the best pilot and don't want to run into anyone or anything while trying things.
I have a 2308 1100kv motor, GWS 10X4.7 direct drive prop and 2S 1050 mah battery. It flew for about 8 minutes and still had time left in the battery.
Overall it is a complete success. I'm very happy with the design.
Now that I know it flies good I'm adding lights for night flights. I weighed my light package and all up weight is 1 ounce. I'm sure it can handle that no problem. The camera i had on it probably weighs more and it didn't effect it any.
I had the camera at the Cg...
My Scorpio weighs 17.2 ounces with 2S battery - ready to fly.

Danford1

Here are a couple more pictures, ready to fly.

what you call boring is what I call controlled..
and a well controllable model is what is wanted..anyone can chuck a model about, but being able to do precise flying is more important..
please post the videos .... Dave

I'm sorry, I thought I did post them.
I'll try again.

#1

Scorpio plane. First flight of home brew plane. Feb 12, 2012, indoors. (9 min 17 sec)

#2

Scorpio plane with onboard camera, indoors, 2-14-12. (3 min 20 sec)

I hope those links work.

Danford1

You guys ever think of just heat bending the W into the foam ... one continuous surface , smooth transitions... maybe even stronger , no glue joins ... KF too

This worked great on my Jerbear Corsair

A single sheet heat bent version will be a nice indoor option.. 3mm depron with a bit of CF bracing if needed..well light and it should go well slow..

good job on your maiden, its a nice and easy steady flier.. you will enjoy chucking it about outside as well, its maneuverability will surprise you..... and what a great indoor site... weve nothing like that over here, I am envious..

That indoor site is called the Ultimate soccer dome. It is in Pontiac Michigan. I have to drive a 1/2 hour to it but it is worth it.
The bad thing is it is only on Tuesdays from 11AM - 1PM. Just 2 hours once a week plus $6 each visit.
It is only open for flying in the winter... November to the end of March.

There usually is more people and planes flying then when I took the videos. It was Valentines day and I guess most people were busy with that. I brought my girlfriend there and we went out after flying for her portion of the Day... To her Valentines Day is one of the top 3 most important days of the year. The other 2 are her birthday, and Christmas.

I was supposed to go to an Ice Fly today (it is winter here) but the wind was 20-30 mph so I stayed home. I know from flying my Caps in even little wind blows them around. The outside angled up surfaces provide a lot of leverage for the wind... Rather than smash up and have to repair my planes, I just stayed home and worked on a flyguy.

Danford1

Subscribed keeps taking me way too long to find this post LOL