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Old Apr 28, 2011, 05:33 PM
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HK and their kits have really improved my hobby and engineering skills recently...LOL Thx for all the info guys. I need to get some clear 3M packing tape. Already have my hot glue gun from my wife. I really like the convience of swapping the motor in and out with the bullet connectors. Reason for the international purchase was because everyone seems to agree the stock electronics are crap and I needed some other items from them as well not carried in the USA warehouse.
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Old Apr 29, 2011, 10:36 AM
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Hello all, I have just completed a complete covering of fibre glass on a bare kit for a new super powerful Skyfun

I used very thin Glassfibre cloth 48g ( http://www.ecfibreglasssupplies.co.u...27mm-wide.aspx ), and did 3 complete coats

It now weighs in at 560grams but it tough as old boots
Just looking for advice on what setups I could use to power this monster, I have a normal skyfun with 60amp esc, Turnigy2836 brushless Outrunner 2350kv, 6x4 prop and 4 cell nano tech 2200 bat, and that flys very nice.

I want to at least double the thrust of the normal one, maybe even push to 3 times 8)

So I recon a 120amp esc, ext ubec and 2 x 3cell 2200 so far

Anyone know what type of motor and prop combo I could use for this power?
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Old Apr 29, 2011, 11:48 AM
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Quote:
Originally Posted by AndyInKent View Post
Hello all, I have just completed a complete covering of fibre glass on a bare kit for a new super powerful Skyfun

I used very thin Glassfibre cloth 48g ( http://www.ecfibreglasssupplies.co.u...27mm-wide.aspx ), and did 3 complete coats

It now weighs in at 560grams but it tough as old boots
Just looking for advice on what setups I could use to power this monster, I have a normal skyfun with 60amp esc, Turnigy2836 brushless Outrunner 2350kv, 6x4 prop and 4 cell nano tech 2200 bat, and that flys very nice.

I want to at least double the thrust of the normal one, maybe even push to 3 times 8)

So I recon a 120amp esc, ext ubec and 2 x 3cell 2200 so far

Anyone know what type of motor and prop combo I could use for this power?
I think, first, you are going to have to figure out a larger motor mount.
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Old Apr 29, 2011, 12:22 PM
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Joined Mar 2011
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That shouldnt be an issue as I have friends at a local car and bike mechanics who can mig weld any shapes I give em
I will sort that out as soon as I work out after all the power requirments and motor etc...

I will grab a couple of shots of it in a while and post so you can see her in her new coat

EDIT: Put the pics on this thred http://www.rcgroups.com/forums/showp...82&postcount=3
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Old Apr 29, 2011, 02:44 PM
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Looks like it will be a very tough bird!

Hopefully your fiberglass job will be strong enough at the tail on either side of the motormount hump. This is where the fuselage tapers to its thinnest but will also receive a lot of stress from such a powerful motor setup.

You should probably add to your motor mount design an aerodynamic cone in front of the motor, as well as a larger base that will interface with both the top and bottom of the fuse.

Will you glass the elevons or replace them entirely with something more exotic than the originals? Stronger hinges, metal gear servos, metal clevis connectors and control horns might also be needed.

Did you put any reinforcing rods inside the tails or will glassing be enough? I don't have any experience with fiberglass.

You'll have to fly it on a humid day, so you can get a picture of the foggy shockwave cone forming around it!!
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Old Apr 29, 2011, 03:47 PM
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Originally Posted by soundguy63 View Post
Looks like it will be a very tough bird!

Hopefully your fiberglass job will be strong enough at the tail on either side of the motormount hump. This is where the fuselage tapers to its thinnest but will also receive a lot of stress from such a powerful motor setup.

You should probably add to your motor mount design an aerodynamic cone in front of the motor, as well as a larger base that will interface with both the top and bottom of the fuse.

Will you glass the elevons or replace them entirely with something more exotic than the originals? Stronger hinges, metal gear servos, metal clevis connectors and control horns might also be needed.

Did you put any reinforcing rods inside the tails or will glassing be enough? I don't have any experience with fiberglass.

You'll have to fly it on a humid day, so you can get a picture of the foggy shockwave cone forming around it!!
Hi there,

Yeah it is very strong! Its turned out a lot stronger than I imagined lol
The motor mount area has a couple extra layers for strength as I have had that area go on my normal skyfun.
The motor mount will be welded ali, I will also be forming a nice aerodynamic cone like you say althought it will be more of an outlet for air from inside the plane as airflow will need to be good for all the power.
The elevons I will make from wood and cover in glass, still looking for the ideal stuff I use 450 class heli blades on my normal one, they are very good as flaps :P
Still looking at hinges etc as they will all need to be strong, i have plastic ones but they have broken on my on the normal bird. Idealy need to find thicker ones.

Hahahaha @ shockwave, I wish :P
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Old Apr 29, 2011, 03:50 PM
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You can see the 450 heli blades in action in this vid :P

http://www.youtube.com/watch?v=fnjNkvJh80A
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Old Apr 29, 2011, 07:18 PM
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Melbourne, Australia
Joined Mar 2009
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Quote:
Originally Posted by AndyInKent View Post
Hello all, I have just completed a complete covering of fibre glass on a bare kit for a new super powerful Skyfun

I used very thin Glassfibre cloth 48g ( http://www.ecfibreglasssupplies.co.u...27mm-wide.aspx ), and did 3 complete coats

It now weighs in at 560grams but it tough as old boots
Just looking for advice on what setups I could use to power this monster, I have a normal skyfun with 60amp esc, Turnigy2836 brushless Outrunner 2350kv, 6x4 prop and 4 cell nano tech 2200 bat, and that flys very nice.

I want to at least double the thrust of the normal one, maybe even push to 3 times 8)

So I recon a 120amp esc, ext ubec and 2 x 3cell 2200 so far

Anyone know what type of motor and prop combo I could use for this power?
This is my 6s skyfun, went over 140mph. Not pretty, hardly recognisable! No glass, just lots of carbon. Motor mount is 50x50x3mm aluminium angle screwed into a piece of 6mm ply sandwiching the carbon between. Go with balsa TE stock for elevons and big MG servos. Laminating film works well over balsa too.

I used a turnigy outrunner H3126 but you're way better off with a scorpion. Buying junk isnt good economy

A quality inrunner would be even better still.

Ian
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Old Apr 29, 2011, 07:25 PM
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Oh and prop was 6.5x6.0 for 26500rpm on 1300kv turnigy outrunner on 6s
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Old Apr 29, 2011, 08:59 PM
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Originally Posted by NinetySix View Post
Oh and prop was 6.5x6.0 for 26500rpm on 1300kv turnigy outrunner on 6s
My guess is it will take around 2000 watts to go 140? This is a guess based on my 3s going around 90 with 520 watts?



(522 watts*(140/90)^3) = 1965 watts.
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Old Apr 29, 2011, 09:17 PM
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Originally Posted by Rich in ILM View Post
My guess is it will take around 2000 watts to go 140? This is a guess based on my 3s going around 90 with 520 watts?



(522 watts*(140/90)^3) = 1965 watts.
Quote:
inflight it pulled 26500rpm, 21.9v, 60.1a, 1316w and did a best of 140mph upwind and 153mph downwind according to the rcspeedo doppler app on my HTC. did a few 125's while still getting her dialed in.
I guess its tricky to compare Watts/MPH without factoring in motor efficiency, prop efficiency and airframe drag. Very happy with the 36mm outrunner on 6s, but its a little heavy.
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Old Apr 30, 2011, 12:05 AM
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Originally Posted by NinetySix View Post
I guess its tricky to compare Watts/MPH without factoring in motor efficiency, prop efficiency and airframe drag. Very happy with the 36mm outrunner on 6s, but its a little heavy.
Your's is quite a bit more efficent than mine. It only needs around 480 watts to do 100 MPH.
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Old Apr 30, 2011, 10:02 PM
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My SkyFun finally had her maiden flight today with one of our best pilots flying and me launching. It flew very smoothly and had plenty of thrust and a lot of speed at 1/2 throttle. Absolutely no loss of altitude on the hand launch, but I did chuck it pretty hard.
Required almost full right trim, which may be the torque of the larger prop. Roll rate to the left was about 3x the roll rate to the right after trimming.
I have to adjust the clevis out a turn or two.

Was also faster than I expected at full throttle but was quiet and really stable through various maneuvers. Landing was very slick with a blip or two of the throttle to leave the prop level with the ground then gliding for the last 40 feet. Slid for about 20 more feet on the freshly mowed landing strip.

I need to add more cooling vents for the new ESC that is now under the end of the hatch.

Then practice, practice and more practice before I add a higher KV motor and a smaller prop to start advancing the top speed.
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Old May 03, 2011, 05:11 PM
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She flew again Sunday but this time with an 808 keyfob camera mounted flat on the right shoulder just inside the fin. This didn't effect trim much but I could tell she didn't hold enough energy when going vertical.
The video was less than a full success because the high thin bright overcast would blow out everything, even the canopy and fuselage would white-out, when the ground wasn't in view. This is the opposite of what should happen, the camera should underexpose the visible parts of the aircraft when pointed at the bright overcast but apparently it was just too much.
So the exposure when banking, diving, or inverted is great as the nice green scenary is perfectly lit. But the majority of the 5 minute flight is an almost entirely white screen in level flight with the camera pointing a couple of degrees up.
I've already ordered a much higher speed motor and larger ESC. Should be here in a few days.
I'm also deciding on a new camera but haven't ordered anything yet.
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Old May 05, 2011, 10:10 AM
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"Moderate" Skyfun

I have 3 Skyfuns which are just over 100+ to 90+ and a new '"moderate" Skyfun. I really wanted something that took advantage of Skyfun's great speed envelope, toughness, and no landing gear to break. I, also like it's ability to fly in high winds which the stock design didn't have enough power to do. Anyway I came up with this motor http://www.hobbypartz.com/86ma07-2215-1950kv.html
With a 6x4 prop and 3s battery. Like all Exceed motors I think it is more than the 1950Kv rating. My watt meeter says 28 amps and just over 300 watts.
That translates into a plane that is just over 200 watts per pound and will fly in the low 80 MPH bracket.
It flies great! I took it off this morning in 15+ winds and it did everything well. While it isn't psycho fast like the the other 2 it is still quite fast and will fly into the wind where the stock Skyfun would give up. It, also, flies well at low throttle settings and is very easy to land with just a touch of throttle. So if you want a great every day flier (Trainer?) that is quite a bit quieter but will still do 80+. This is not a bad deal for $16.00 (motor).
One final thing. This motor will only fit the Skyfun's vertical motor mount holes instead of the horizontal. This means the vertical holes have to be drilled a very small amount to accept the screws. After that everything fits fine and you can use the stock 25 amp ESC. This is how the plane should of come from the factory!
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