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Well that's 50% heavier than mine! My latest (I've built 3 over the years going right back to the original single channel in the 60's) comes in at 300grams (10.5oz) with an Axi 2208/34 & 450mah 3s battery. It's double covered in mylar film then tissue & dope so I don't know how yours came out so heavy.

Edited By John Lee on 30/09/2019 21:40:38

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Sharkface was revisited, and the plan reissued, in Radio Modeller, February 1989.
Gordon Counsell, the builder/reviewer didn't have the ultra-light gear that we have today. His version weighed 14.5 oz and flew very well, powered by a Frog 100 diesel.

The 1989 reissued plan is clearly marked, "Recommended flying weight 15oz.", although I think that should probably be taken as "recommended maximum".
Anyway, Sharkfaces weighing 14/15 oz. are not rare, so you'll be OK! It's a fast flyer at any weight!

The ultra light examples mentioned are probably all electric (not for me). I have one half-built that will be powered by a PAW 80 or 100 (same dimensions and weight).

Edited By brokenenglish on 01/10/2019 09:04:41

Edited By brokenenglish on 01/10/2019 09:09:59

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Posted by brokenenglish on 01/10/2019 09:02:18:

Sharkface was revisited, and the plan reissued, in Radio Modeller, February 1989.
Gordon Counsell, the builder/reviewer didn't have the ultra-light gear that we have today. His version weighed 14.5 oz and flew very well, powered by a Frog 100 diesel.

The 1989 reissued plan is clearly marked, "Recommended flying weight 15oz.", although I think that should probably be taken as "recommended maximum".
Anyway, Sharkfaces weighing 14/15 oz. are not rare, so you'll be OK! It's a fast flyer at any weight!

The ultra light examples mentioned are probably all electric (not for me). I have one half-built that will be powered by a PAW 80 or 100 (same dimensions and weight).

Edited By brokenenglish on 01/10/2019 09:04:41

Edited By brokenenglish on 01/10/2019 09:09:59

Thanks that's interesting to know I might try it when the weather perks up, I have a 6x4.5 on it but might try more pitch if it needs a little more if not I'll hang it in the garage and build something else.

Dave

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Posted by David Still 1 on 30/09/2019 21:23:15:

I have just completed a sharkface electric powered 1200kv motor on 3s lipo my AUW is 15.4oz which seems very heavy any thoughts?

 

Dave

Mine weighs about the same after several repairs, with three servos and a 1000 mah 3 cell lipo and it  flys fine

Edited By FlyinBrian on 01/10/2019 13:26:58

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Posted by FlyinBrian on 01/10/2019 13:25:13:
Posted by David Still 1 on 30/09/2019 21:23:15:

I have just completed a sharkface electric powered 1200kv motor on 3s lipo my AUW is 15.4oz which seems very heavy any thoughts?

Cheers that's good to know I could save an oz if I put a smaller battery in but I'll try with what I have first. What size prop are you using?

Dave

Dave

Mine weighs about the same after several repairs, with three servos and a 1000 mah 3 cell lipo and it flys fine

Edited By FlyinBrian on 01/10/2019 13:26:58

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I have a leccy powered one now with two alternative wings, one for rudder/elevator and the other with a slightly flattened out wing with ailerons. Don`t know the weight but they go like stink. I built the original when it was published. It used a Cox TD049 and a UK valve/transistor Rx minus its case and modified to be relayless thus allowing me to use a tiny 22.5V HT battery plus 1x and 2x AAAs so it must have been quite heavy by today`s standards! Sheer fun.

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Ok I managed to get to the flying field today and did a couple of test throws and got a glide so tried some power but all that downthrust just pulled her to the ground so a second attempt full power throw and the same result but a broken prop curtailed any further attempts any ideas what I'm doing wrong here?

Prop 6x4 1200kv 160w motor on 3s.

Dave

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David, they need to be launched with the thrust line level!!!
i.e. about 10° nose up if you've built as per plan!

Think about it. At the instant the plane leaves your hand, there are no aerodynamic forces except for thrust and weight (no lift). If you don't launch nose up, the downthrust will pull the plane down to the ground before you have enough airspeed to generate lift... A firm throw with the thrust line horizontal should cure your problem.

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Have you got elevators on it? If not, and its sinking after the launch, a quick wiggle on the rudder will lift the nose!

I used to fly mine with an Elmic Compact (compound) escapement and a Babe Bee .049. Just giving a quick-blip on the button after the launch was enough to lift the nose on a calm day. On a windy day - which they were designed for - this isn't necessary!

I really ought to build another......

--

Pete

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  • 2 months later...

HI , I have built a Sharkface with Electric Outrunner motor and rudder /elevator/throttle control.

The model weighs 14 .5 ounces ready to fly.

The question I have is what it the recommended power in Watts and prop size for an average flying Sharkface?

The motor I have is a Cheetah A2212-15, 930RPM/V, max current 12A Max Amps, 133W for 60 seconds

The motor weight is 47g/1.65oz.

The recommended prop size is APC8*4E 72Watts or 9*4.5E 108Watts. These values are with a 3S battery.

I would appreciate advice from anyone with experience with an electric powered Sharkface

Barry

 

 

 

 

 

Edited By Barry W on 08/12/2019 15:29:32

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Thanks GeeW, that's just the information I was looking for..

They don't have many Sharkfaces over here in "The Land of the brave and home of the free".

The folks in the local RC club think I am a crazy Brit as they seem to mostly fly "out of the box" foam planes.

I know Eric Cluton is also in the US but is quite a drive up to Georgia from central Florida..

Also he is a die=hard diesel man so probably has no experience with electric.

Barry

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I'm building one. It will be powered by an electric motor pulled from a P38 Lightening foamie. I don't have much experience with electric motors either!

Having said that I have been given a Cox 049 with five litres of high octane glow fuel so I may build a second one for that.

I am going to have a go at covering the wing in tissue over doculam.

Picture of the Sharkface fuselage alongside a somewhat bigger project.

now warp ya bugger.jpg

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For flying in various conditions Barry, I use a variety of lipos with an 8 x 4 sports prop.

Due to belly landings, I use a tough black prop unknown make

The 12v motor gives the option of 2S or 3S packs, from 500 - 800mAh

In light breeze conditions, the 2S is fine for flight and in windier conditions I have a heavy 800ma 3S

Edited By Denis Watkins on 09/12/2019 06:52:37

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My Sharkie uses a 2S 800 LiPo which yields a flight time of about 10 minutes if I'm gentle and 8 minutes if I'm not. I also have a small bit of lead in the nose so a smaller battery would not be an advantage.

Props are held on with an 'O' ring which improves prop life significantly.

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Without digging mine out of the loft I cannot remember the electric set up I use but at a guess 3s 800.

I built the original when it was first published and fitted a Cox TD 049. Thinking that 1/8th" rudder travel must have been a misprint I used 1/4" Yikes! And no throttle!

I also have another wing for it with 1/2 the dihedral and ailerons. Obviously more rudder travel was needed on this but made the mistake of trying to fly the rud/elev one on the wrong Tx memory. Good job they are tough.

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