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#1 Nathan Schmoekel Jul 10, 2012 03:43 PM

light weight project
 
7 Attachment(s)
Teaser pics first....

What's in the box?

#2 Flyextreme Jul 10, 2012 04:28 PM

So what is it, that's in the box?

#3 blunight Jul 10, 2012 04:30 PM

It may be "old school" but I'm old and I also like pink planes...what's it called and where did you get it?!

#4 Flyextreme Jul 10, 2012 04:42 PM

Quote:

Originally Posted by blunight (Post 22127640)
It may be "old school" but I'm old and I also like pink planes...what's it called and where did you get it?!

Zackly!

#5 Nathan Schmoekel Jul 10, 2012 05:04 PM

It's called the Fire Fly, it's not widely available yet:cool:
There are only three or four in existence right now. They are testbeds for working out a one-piece fuselage version of the design.....although time will tell if that's actually any lighter, mostly just a little easier to build for the end-user.

One has been built with a pair of 9gram servos and one 6g for the elevator, running on a single LiPo cell the all up weight was 7.6oz:eek:
BUT this is not a corner cutting, stupid light DLG... it's a revisit of older designs like the Super Gee, but rearranged, a bit and built with newer materials and methods. The wing, for instance, is a Zone-2 based foil with a mid-aspect forward swept planform.

Mine is actually just about built, I have all the photos taken, but need to organize them and get to typing. I have a two cell and BEC going in it right now, it's going to weigh 8.5oz for the first flights. When a certain package arrives I'll convert to a single cell and booster; that will drop her well below 8oz.:)

#6 c.raynes Jul 10, 2012 05:40 PM

Next purchase for sure.

#7 The_Builder Jul 10, 2012 07:00 PM

:cool:

#8 GaryO Jul 10, 2012 08:32 PM

What is the wing area?

#9 Flyextreme Jul 10, 2012 08:48 PM

Well, if they are not available, I gotta have one for sure.

#10 ShadowFalken Jul 11, 2012 01:32 AM

More dead butterflies?! :eek::rolleyes:

#11 Nathan Schmoekel Jul 11, 2012 07:45 AM

Quote:

Originally Posted by GaryO (Post 22129588)
What is the wing area?

315 ish square inches.

#12 Nathan Schmoekel Jul 11, 2012 08:45 AM

6 Attachment(s)
Ok, guess it's time for a bit more....
This project started with a question.... Why are one piece fuses lighter than two piece fuses?? Simple answer...Ideal distribution of mass and lack of redundant material. SO.... The elephant in the room is the boom-pod tenon overlap! Not only is it double thick and heavy, but it's AFT of CG....That's not where you want extra weight, and that's the primary place where one piece fuses are winning the weight distribution battle.

That lead to a simple stroke of genius....move the boom tenon under the wing. It made the most sense to use the double thick tenon area as a wing support...the strength is already there, plus the mass of the tenon overlap is moved forward!

Admittedly, these are not completely new ideas. All you need to do is go back a few years and look at the two piece high-pylon DLGs, like the Super Gee; but their weak point was the pylon. Because of the mass hanging so far below the wing, the wing mount had to withstand a huge twisting side load during launch....so how to mount the wing???

Hey, the B-3 mounts the wing right to the boom.....SO mix in a little red-neck B-3 style wing mount done with aluminum screw posts and VIOLA! Now we don't have to worry about breaking the a wing pylon! Which further means there are no worries about ballast weight twisting the fuse off the wing. The ballast is even contained within the tenon overlap area, so ballasting heavy is not an issue:cool:

Now, the only structural advantage a one piece fuse has is being able to shape the boom oval... which is cool, but perhaps a bit overrated:rolleyes: I suppose you could still argue that a wing saddle supports the wing better, but no issues with the screw posts so far.... even using nylon screws! If things were moving and twisting the screws would surely give out.

Well enough babble... MORE PICS :D:D

#13 JimZinVT Jul 11, 2012 05:17 PM

:popcorn:

Dumb question #1: Is that screw post custom-bent, or do they sell them with a curved head?

#14 DLGjunkyard Jul 11, 2012 06:16 PM

Quote:

Originally Posted by JimZinVT (Post 22137853)
:popcorn:

Dumb question #1: Is that screw post custom-bent, or do they sell them with a curved head?

http://www.rcgroups.com/forums/showthread.php?t=1666627

#15 Nathan Schmoekel Jul 11, 2012 08:30 PM

OOPS.... somebody made a connection:eek: will the haters come out now? :o:rolleyes:

But even without fancy jigs, it's not that tough to bend them either:p Just clamp the edge you need to bend in a vice and tap it with a hammer / screwdriver combo till you get a good angle...then flip it and repeat:) Perfection of the angle that meets the mounting area is not necessary, CA fills the gaps and inhibits movement...the wrap further distributes the stress. No movement, no wear, no issues:cool:


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