Sigma

They stay up by magic!
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Sundancer
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Re: Sigma

Post by Sundancer »

Your power pod looks like a good solution Carl
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Carl
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Re: Sigma

Post by Carl »

Just a couple of pictures showing progress:

WP_20181120_20_43_41_Pro.jpg
WP_20181120_20_44_04_Pro.jpg

I just need to make a new centre cover piece to replace the one shown in the pictures, and sort the electronics...
Carl

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Wayne_H
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Re: Sigma

Post by Wayne_H »

Carl,

Your embarrassing me :oops: ;)

I shall have to go to the quack for the surgery to have my digit extracted (digital surgery?? :shock: ), so I can finish off my Sigma :lol:
Cheers,

Wayne
Once a Retrobate, always a Retrobate............ ;)
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Carl
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Re: Sigma

Post by Carl »

Wagga_Wayne wrote: 21 Nov 2018, 12:03 Your embarrassing me :oops: ;)
Sorry Wayne :cry: Just to make you feel better I'm sorting the electronics now :lol: (I did have the slight advantage of starting with a ready built Sigma) ...

WP_20181122_14_01_34_Pro.jpg
ESC at base of pylon - the battery pack will go beneath wing in the weight box

WP_20181122_14_02_03_Pro.jpg
Motor timer behind base of pylon for easy setting changes between flights
Carl

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STILL LEARNING
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Carl
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Re: Sigma

Post by Carl »

I have a running setup with my timer. On the video the timer is set for 10 secs at 30% power:



So just need to make a few changes to the code and install a push button that is activated on full up elevator.
Carl

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Wayne_H
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Re: Sigma

Post by Wayne_H »

OMG, I've actually done some more work on the Sigma :shock:

The tailplane is finished & covered; "3-ply" layed up from thin veneer & laminating resin (since I'd run out of thin ply & the nearest shop is 200km away) to make doublers & formers; fuse sides made & joined; fin & rudder cut & assembled; one piece wing cut in half and plug-in dihedral joiners retro-fited; storage/transport box parts cut & primed.

At this rate, I may actually get it finished this year!?!?
Cheers,

Wayne
Once a Retrobate, always a Retrobate............ ;)
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Wayne_H
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Re: Sigma

Post by Wayne_H »

The transport/storage box is finished. Unlike the box design in the original article, this one is made from aluminium angle & coreflute recycled from an old real estate sign. Colour is more trim tape from HK (I've got heaps of the stuff!?! :shock: :oops: ). The wing halves fit in the lid while the fuse, tailplane, 1+1 Tx, motor batteries & a 2 cell charger fit in the bottom portion.
No, the fuse is not quite finished
No, the fuse is not quite finished
Sigma box.jpg
The wing halves and tailplane are finished with HK trim tape (what else?!? :P ). The rudder just needs to be hinged and a fairing made over the wing, a final coat of paint then the fuse is finished :D .

Hook up the radio, fit the folding prop, then balance & it's test flight time :D :lol: :D
Cheers,

Wayne
Once a Retrobate, always a Retrobate............ ;)
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Carl
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Re: Sigma

Post by Carl »

Looking great Wayne 8-) Even a case to match :D Keep the momentum going at it'll be flying in no time.
Carl

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Carl
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Re: Sigma

Post by Carl »

I managed to crack the tail fin on my Sigma after a stall close to the ground. The plan was to refurbish it after some flights with it, so now's as good a time as any. I'm really happy with the way it flies and is worth doing.

I'm in the process of stripping the very badly applied covering. Once I've done any necessary remedial work it will be recovered with yellow film again on the flying surfaces. The fuselage is covered with nylon and spray painted, so I'll prep that and respray with some fresh blue.

I want to run the elevator control through the fin and will probably sandwich balsa with thin ply either side - the current setup was a bit wobbly, so want to take the opportunity to stiffen it a little.
Carl

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STILL LEARNING
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Wayne_H
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Re: Sigma

Post by Wayne_H »

Carl wrote: 02 Jun 2019, 12:39 I managed to crack the tail fin on my Sigma after a stall close to the ground......
Carl,

2 aviation proverbs/truisms come immediately to mind:
  • he who stalleth falleth, &
  • beware the ground, lest it jump up & smite thee :shock:
I've actually test flown my Sigma, albeit a short flight of only a few minutes. It was over powered & didn't have enough down or right thrust, so I had to constantly try & turn out of the zooming climb. Fortunately the glide is fabulous & rudder response is excellent 8-).

I've replaced the motor with a softer wind (1400kV) & increased the down & right thrust. The weather has been un-cooperative since :x , but is forecast to be on the improve, so watch this space!
Cheers,

Wayne
Once a Retrobate, always a Retrobate............ ;)
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