"DDDC175" - Double Dekker Dead Calmer at 175 grams.
#1

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After the great success with couple of GIANT double dekkers and latest, lightest mono wing creations to add in my fleet, I got a new idea to build the lightest doublewinger after learning few tricks from my last build and the failure of two earlier models, being too heavy for their size, no where near for my intended "slow-low-close" fun flying, but rather a stressful dogs to fly to check my reflexes. LOL.

Giant with the micro doggy.

After each creation learning something new.

Something like this as 'Doubledekker".
At this embryonic stage, my guess is 175AUW, it would be nice if I can beat it lower to reduce the wing load at some 3 grams per decimeter. My last mono winger build flies at 4g/dm, pretty nice for outdoor dead calm but I like to slow it down further to have even more fun during magic twilight hours.

Giant with the micro doggy.

After each creation learning something new.

Something like this as 'Doubledekker".
At this embryonic stage, my guess is 175AUW, it would be nice if I can beat it lower to reduce the wing load at some 3 grams per decimeter. My last mono winger build flies at 4g/dm, pretty nice for outdoor dead calm but I like to slow it down further to have even more fun during magic twilight hours.
Last edited by Joseph Frost; 07-19-2022 at 11:42 PM.
#3

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Lot bigger job than expected, this one will take good 120 hours judging by my last 75 h mono project to fully complete. Extremely delicate, it will take some carbon fiber to make it air-worthy for out door action.
More progress well on its way.

Delicate sanding of all cut outs take lot more time than cutting it out!

Handle like eggs job!
More progress well on its way.

Delicate sanding of all cut outs take lot more time than cutting it out!

Handle like eggs job!
#4

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Outer wing supports test fit, and start on the main fuselage frame.

No strength whatsoever at this stage of build.

Slight positive lower deck.

Careful cutouts of center fuse X.

No strength whatsoever at this stage of build.

Slight positive lower deck.

Careful cutouts of center fuse X.
#8

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Double dekker is now bonded together for overnight cure and further carbonizing to stiffen it up.

Elev. and Rudder servo hook up.

Frame joined together.

Adjustable Aileron joiners in place.

Depron landing gear cuts outs.

Keeping the weight to minimum.

Elev. and Rudder servo hook up.

Frame joined together.

Adjustable Aileron joiners in place.

Depron landing gear cuts outs.

Keeping the weight to minimum.
Last edited by Joseph Frost; 07-26-2022 at 01:53 AM.
#9

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Bit of a nightmare today! After hooking up and adjusting my Ailerons, the 9 gram servo seem to strip the gear at extreme end travel on left side. Quite a job and total waste of time to remove and replace it, as my intentions was to install the MG one but changed my mind to save the weight!.
Well, double the weight but MG one is in and more reliable to control the large four control tabs, more CF had to be fitted to the whole frame to make it flyable, unfortunately adding more weight as I go, so my planed AUW target is just another wishful thinking.

Now fitted with metal gear servo at 19g. AUW!

It needs more carbon!

Adding on weight!
Well, double the weight but MG one is in and more reliable to control the large four control tabs, more CF had to be fitted to the whole frame to make it flyable, unfortunately adding more weight as I go, so my planed AUW target is just another wishful thinking.

Now fitted with metal gear servo at 19g. AUW!

It needs more carbon!

Adding on weight!
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MAIDEN DISASTER!
It lasted less than 10 seconds, after rotating to some 3 meters I didn't know if I was "Arthur or Marther"! It was just about totaly out of control, rolled on me twice, so I was in such a panic state can't even remember which way it rolled as it happened so quick.
It was only a miracle I managed to slam it down on its landing gear, which suffered a minor brake but I can't believe there is no structural damage to the frame after close inspection, because after this short horrific experience I was sure it's the end of this one.
It took only few more grams of added weight to fix it shortly after but more soul searchin will be needed to find out what's wrong.
Sadly, while being in a hurry to test it in semi darkness, twilight eve dead calm I didn't bring my cap cam to record the drama which would be very handy to analyze the problem. LOL- just a part of RC modeller life.
It lasted less than 10 seconds, after rotating to some 3 meters I didn't know if I was "Arthur or Marther"! It was just about totaly out of control, rolled on me twice, so I was in such a panic state can't even remember which way it rolled as it happened so quick.
It was only a miracle I managed to slam it down on its landing gear, which suffered a minor brake but I can't believe there is no structural damage to the frame after close inspection, because after this short horrific experience I was sure it's the end of this one.
It took only few more grams of added weight to fix it shortly after but more soul searchin will be needed to find out what's wrong.
Sadly, while being in a hurry to test it in semi darkness, twilight eve dead calm I didn't bring my cap cam to record the drama which would be very handy to analyze the problem. LOL- just a part of RC modeller life.
#12

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Back in order after few more static checks and re-trims for another stressful re-maiden. This isn't the first time I had some control issues with scratch build BI's, some of them were and still are an absolute dogs to fly, so nothing will surprise me if this one ends up in trash, as it would be totaly un-repairable if damaged structualy, always ready to build another one, and LOL.

10 meters of Carbon helped to keep it structualy sound after the maiden crash, Tx to L/G absorbing the impact.

All damage fixed ready for another test flight.

10 meters of Carbon helped to keep it structualy sound after the maiden crash, Tx to L/G absorbing the impact.

All damage fixed ready for another test flight.
#13

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Four flights today on 4 various capacity batteries, 300-550mA, on lighter packs it might need slight more of prop down thrust. Also testing 3 different props after cutting out new alloy spacers for precision fit to different prop addaptor. Seems like 9x4.7 is the best so far but trying hard to get 9 or even 10 by 2.5 low pitch CF ones which would be a perfect match for this set up.

Cutting out alloy sleves for perfect prop fit.

The best so far, 9x4.7 orange one.

Cutting out alloy sleves for perfect prop fit.

The best so far, 9x4.7 orange one.
#14

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This hobby is going down the gurgle! Can't get anything I need anymore, not even such a basic thing as light prop variety! Back to cutting down, modifying from what I got on hand. Anyone with light slow flying 9 to 10 inch by 2.3 to 3 pitch send me a PM, TX.

Trying to make my own 10x2.5 from what I have on hand.

Trying to make my own 10x2.5 from what I have on hand.
#17

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TX Mate, I got thousands of videos on YT over the years with all sorts, these micro lights I don't bother to load on as I fly them mainly late evenings during dead calms in twilight darker hours so the footage doesn't come so well.
I fly them daily, just over the fence, this eve flew 3 models, incl. this BI winger, and after bit of hard 3/D manouver I could hear a little snap, thinking it might be just CF ripped out at some joint but after landing it was clear.
The weakest link, Elevator "L"shape broke off, still fully under control but with next builds I will make that corner bit stronger.
This model at 230grams is little too heavy for that weak point during hard manuevers. Easy fix by foam glue and

Bit of a weak link, the corners of the "L" shape Elev. moving tabs,now reinforced with strong tape.
ading some tape over the break but will have to take it little easier in the future on the stix.
I fly them daily, just over the fence, this eve flew 3 models, incl. this BI winger, and after bit of hard 3/D manouver I could hear a little snap, thinking it might be just CF ripped out at some joint but after landing it was clear.
The weakest link, Elevator "L"shape broke off, still fully under control but with next builds I will make that corner bit stronger.
This model at 230grams is little too heavy for that weak point during hard manuevers. Easy fix by foam glue and

Bit of a weak link, the corners of the "L" shape Elev. moving tabs,now reinforced with strong tape.
ading some tape over the break but will have to take it little easier in the future on the stix.
#20

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I got a hand on an old rarity, 10" indoor carbon fiber prop, very light at only 5 grams with nice and solid blades, no flex, to upgrade the cheap plastic 9x5 I have been using so far. After initial check run the prop was way out of balance and much too pitchy for the motor getting to cooking state in no time!
Minor mod by dramatic pitch reduction and re-balance to perfection did the trick.
Ready for more fun after this cold windy crap spell.


Dramatic pitch reduction.

Ready for action.
Minor mod by dramatic pitch reduction and re-balance to perfection did the trick.
Ready for more fun after this cold windy crap spell.


Dramatic pitch reduction.

Ready for action.