Durachko

My Feedback: (3)

I'm stoked to fly this critter!!!

EDIT 08/25/2005: Oh man . . . does this thing FLY!!! I think it's safe to say this is one of the best flying aircraft I have EVER flown. Sweet!!!

Will post some pics of the finished bird soon. SEE BELOW

Followed the plans as closely as possible.

This is a gorgeous kit and the quality is superb.[sm=thumbup.gif]

The manual could use some editing but is quite good as well. (Perhaps I am too finicky when it comes to such things.)

The decals that came with the kit are too scrunched together and there's some bizarre/annoying white background on the decal sheet as well. (Again, I'm nitpicking.)

Questions:

1) My CG requires I put the LiPo pack almost all the way to the nose - she's a bit tail heavy. If I machine a knurled brass prop nut (say 15 grams or 1/2 ounce) for the A20-20L will the extra mass cause any performance problems? I'm mainly concerned with loading the motor but my gut tells me I won't actually hurt the thing. (I'll post a total weight soon too. Don't have that info with me right now. I *should* be on target with all-up weight but won't be shocked if she's on the heavy side.)

2) I'm using a 5 channel Rx and a Futaba 8 channel Tx. I'm a little new to programming/mixing and am a tad confused [sm=confused.gif] with the mention of Flap>Elevator mixing in the instructions. The manual says the prototype was flown setup with "c. 100% Flap>Elevator mixing on Landing switch 1. (Down Flap/Up elevator.)" on a JR 8103 Tx. My Tx is a heli setup with a pot (dial/knob) for flaps. How is this mixing supposed to work? Were I flying the JR as described in the manual would I flip a switch and the flaps (flaperons) would go to a preset amount of down and the elevator to some empirically determined amount of up such that my control surfaces would be in some preset landing configuration? How does this compare to using an airbrake configuration (positive/upward flaperons)? How far (degrees or trailing edge linear measure) should the ailerons typically droop for landing?

I guess that's enough for now.

EDITS BELOW:

All-up weight as pictured below comes to just over 20 ounces (with the custom spinner nut weighing in at around 1.2 ounces all by itself). Motor seems to handle the spinner just fine although it's obvious the mass is causing some momentum issues which I don't think will really matter. The plans list the high end weight at under 18 ounces so I'm wondering how I got so heavy? Anyway, the bird seems to have more than sufficient power so I'm not worried much. Hope to take maiden flight this weekend or sooner. Still want to add a pilot to the cockpit and do some tailfeather painting but I'm a bit scared to add any more weight. The underside picture shows the LiPo pack about where it would have to be to balance the plane without the ~1.2 ounce custom spinner nut. I foam taped my tail control servos in place and secured them further with zip ties and a backer so the foam wouldn't get cut into by the ties. (The knurl job on the spinner looks ugly because it wasn't done properly.)

How much of one of those little spray cans of Testor's paint should I have used to paint the whole bird yellow? Took me a full can so maybe that added a significant amount of weight? I can't see how I could have gotten away with much less though???

08/25/2005: Duh . . . 20 ounces MINUS my 1.2 ounce spinner brings me in at 0.8 ounces over listed high end weight on plans. Still - why am I so tail heavy? How about posting your all-up weights for me to compare with? Anyone else come in tail heavy after the build?

If you'd like to see any of the below pics at their native resolution visit the link below.

http://www.personal.psu.edu/faculty/...Pics/Foamy.htm

JohnVH

My Feedback: (38)

Hi! You will love the plane, there is not another foam plane out there that flies like our supers!

Im trying to figure out why yours is tail heavy, I am running the same setup as you are and my battery is under the leading edge of the wing. I would not bother with the flapperons, they are just if you want something to play with, I do not have them on my SX and it does it all.

Enjoy!

emnm79

My Feedback: (5)

hmm... flap to elevator mix ehh, I've used that to get some REALLY tight loops in glow planes, but I don't know about using it for landing, if you want flaps for landing, just set them up to a switch, or set your dial up so full left=level flaps and full right=full flaps... I've never needed them on a foamy, so I wouldn't even worry about it for landing... If you want the mix for flap to elevator (sometimes called "snaperons"?), you'll need to program it in as a pmix in the radio as up elevator=down flaps and down elevator=up flaps...

rmenke

My Feedback: (13)

Sorry to disgree with your statement. Just completed the RCX planes Illusion. It is just unreal. Have had yaks all the shocks, Northern balsa Stella, Funtanna and a host of others that were disappointing. Unless you find a reasonable way to stiffen the tailfeathers without coppying the Illusion's design, you will be in second place. The old tribute was a good flyer except for the floppy tail and wings in some conditions. The Illusion design stiffens the rear almost equal to a balsa buildup, without much added weight. My first flight was with 15 mph winds, plane flew great even under these nasty conditions. I really abused the plane Sunday and found it flying abnormal, or should I say typical of all foamy past experiences. In checking it out, I found the lower braces running the full lingth of the fuse had broken at the trailing edge, both sides. A little epoxie and 6"of packing tape, and as good or better than new. I am going to modify the rest of my foamys with the same design of bracing and expect big differences, which may keep them out of the trash can. Have a lot of stick time, but little 3-D. After two days flying the Illusion, am doing great torque rolls, rolling circles, elevators to soft landings, the waterfall today. All at once, everying is easy! Oh, by the way, I am 70 years old and have been around the block! You just gotta have one of these things. See www.rcxplanes.com. I will try yours in the near future.

XpastywhiteboyX

My Feedback: (5)

I really wish you would look at the design before you say things like this... The 3D Foamy SX is a laminated design and is the first of its kind. It is 3mm with embeded carcon fiber flat stock. Then laminated with 2mm sheeting. I have flow then line of RCX planes and know the owner bud, he is a nice guy, but the claims you make about the tail being stiffer than the 3D Foamy Super Extra is way off base and untrue. I believe you can see the CAD drawing on their website. also look at the Super extra promo video and the mini sukhoi promo video, I think you will change your mind

RCXPLANES

My Feedback: (1)

rmenke,

I'm Glad you believe in your Illusion. The 3D Foamy SX looks very cool. I have been using the 3 and 5 layer laminate designs for about 18 mo. now and I can tell you that it really stiffens the sheet foam by a bunch. 2 layer does nothing but beyond that it does wonders. It looks like 3D Foamy has done a great job on the SX. I'm sure it flies great. I personally still believe in the triangulated fuse though. Keep in mind also that without adhesives, 2 sheets of 3mm Depron is heavier than 1 sheet of the same size of 6mm Depron. This is according to Depron's spec sheet so you have to choose your places to laminate. I have seen the 3D Foamy Pro Wing and it is quite stiff.

Bud