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Another Skymaster Viper

Old 02-10-2010, 03:17 PM
  #876  
DENTO
 
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Default RE: Another Skymaster Viper


ORIGINAL: Jascat100

Hi Bronte. This is a new mod. Skymaster will be constantly improving the Viper based on the experiences of us who fly them. I am sure the gear doors will also soon have modified cylinders. Enjoy your Viper,It is a winner.

Regards
Jim
Gear door cylinders my VJ has the crappy little cylinders maybe have to replace
REGARDS
JOHN
PS TO ALL THATS
Can some of you give me a final weight on your VJ mine has come out at 23 KG dry with a 160sx SHOT OF OUR FIELD FROM THE AIR We are having a jet meet there in july
REGARDS AGAIN
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Old 02-10-2010, 03:21 PM
  #877  
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Default RE: Another Skymaster Viper

23kg dry?! WOW!

I believe mine is 18.5kg dry, maybe 19kg with 160.

What do you have in yours to make up the extra 4 - 4.5kg!?!? [X(]
Old 02-10-2010, 03:40 PM
  #878  
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Default RE: Another Skymaster Viper

Check your weight, must be giving a false reading [X(]
Mine is 20,2 Kg dry and 23,5 including fuel, with a P200SX (800 gr more than the 160SX engine!)
Old 02-10-2010, 04:41 PM
  #879  
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Default RE: Another Skymaster Viper

Mystery solved... who needs threads anyway? [:-]

The hole is 4.3mm in diameter so that would suggest it was drilled for a 5mm bolt, just missing out on the tapping bit.



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Old 02-10-2010, 04:59 PM
  #880  
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Default RE: Another Skymaster Viper

Wow, looks like the machine shop was equipped with chain saws instead of milling machines!
Old 02-10-2010, 06:32 PM
  #881  
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Default RE: Another Skymaster Viper

lol, it looks a lot worse in the hard lightning and at that magnification.

I wonder if I can use this bolt I found at my mates.


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Old 02-10-2010, 07:28 PM
  #882  
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Default RE: Another Skymaster Viper


ORIGINAL: schroedm

23kg dry?! WOW!

I believe mine is 18.5kg dry, maybe 19kg with 160.

What do you have in yours to make up the extra 4 - 4.5kg!?!? [X(]
HI guys
I realy dont think I have any more in mine than what I see in whats being built, The scales were a set of commercials that my boys use in there business for postage so they
should be ok.but shall check again.Thanks for the replys.
REGARDS
JOHN
Old 02-11-2010, 03:17 AM
  #883  
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Default RE: Another Skymaster Viper

For the rudder clamp, I just used a bolt that would go through the hole & fitted a spring & plain washer & a locknut. Another bolt is is screwed into the front carbon rod. The vertical fin is easily removed. A hole in both sides of the rear fuz allows a socket & allan key in to slacken the clamp bolt & nut. Not normally done, as I transport with the fin in place. My Viper weighs around 18kg dry, with Wren 160.
Old 02-11-2010, 03:27 AM
  #884  
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Default RE: Another Skymaster Viper

John / Carsten,

did you build in servo's with gears made of lead.
That is realy haevy.
The weight till now of my viper is : 17,6 kg(dry)
Only thing what needs to be done is build in 3 lipo's (turbine+landinglights) in the nose, to get the CG right.
Maybe when it's ready total weight dry between 17,9 and 18,2 kg


Fin 672 gram
Elevator 908 gram
Right wing 2600gram
Left wing 2600 gram
tanks+hopper 450 gram
scale cockpit 415 gram
canopy 232 gram
thrustpipe 390 gram
duct 157 gram
Alu.tube for wing 288 gram

fuselage complete with powerbox, 2 powerbox Lipo's, powerbox display and switch, 3 valves(airpower/jettronics), airbottles (2 big and 3 small ), digital suquenser,switch for landinglights
7000 gram (+/- 100 gram)

Turbine complete 1896 gram (jetsmunt Merlin 160)

Regards
Ron
Old 02-11-2010, 03:28 AM
  #885  
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Default RE: Another Skymaster Viper


ORIGINAL: Selleri

Mystery solved... who needs threads anyway? [:-]

The hole is 4.3mm in diameter so that would suggest it was drilled for a 5mm bolt, just missing out on the tapping bit.



that alluminium is to soft to have thread.
i feel a new little project comming with 28ST grade allumium comming.
mm i wonder if i can re-use our festo clamp for this
whatis the EXACT size of that hole? digital calipers please..
i need the sizes as well for the alloy rod as the carbon rod


Old 02-11-2010, 03:30 AM
  #886  
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Default RE: Another Skymaster Viper


ORIGINAL: cgroen

Thanks Ron,
surgery will now begin
Carsten,
How did surgery go?

Old 02-11-2010, 03:45 AM
  #887  
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Default RE: Another Skymaster Viper


ORIGINAL: Ron v U


ORIGINAL: cgroen

Thanks Ron,
surgery will now begin
Carsten,
How did surgery go?

Wow, "now" is a relative term here
I'm fiddling with some software for a little project (ask Sandor ), but hopefully tonight the patient will get on the table, only ***** is that I have to remove the engine and the thrusttube to get to the screw that bolts the fin to the fuse
Old 02-11-2010, 04:48 AM
  #888  
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Default RE: Another Skymaster Viper


ORIGINAL: Ron v U

John / Carsten,

did you build in servo's with gears made of lead.
That is realy haevy.
The weight till now of my viper is : 17,6 kg(dry)
Only thing what needs to be done is build in 3 lipo's (turbine+landinglights) in the nose, to get the CG right.
Maybe when it's ready total weight dry between 17,9 and 18,2 kg


Fin 672 gram
Elevator 908 gram
Right wing 2600gram
Left wing 2600 gram
tanks+hopper 450 gram
scale cockpit 415 gram
canopy 232 gram
thrustpipe 390 gram
duct 157 gram
Alu.tube for wing 288 gram

fuselage complete with powerbox, 2 powerbox Lipo's, powerbox display and switch, 3 valves(airpower/jettronics), airbottles (2 big and 3 small ), digital suquenser,switch for landinglights
7000 gram (+/- 100 gram)

Turbine complete 1896 gram (jetsmunt Merlin 160)

Regards
Ron
BLINKY SCALES
Have a diferent set of scales, tanks full has come out the same 23kg so maybe 19 dry, Anyone,s guess, So go at that.
REGARDS
Old 02-11-2010, 04:57 AM
  #889  
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Default RE: Another Skymaster Viper

ORIGINAL: Ron v U

John / Carsten,

did you build in servo's with gears made of lead.
That is realy haevy.
The weight till now of my viper is : 17,6 kg(dry)
Only thing what needs to be done is build in 3 lipo's (turbine+landinglights) in the nose, to get the CG right.
Maybe when it's ready total weight dry between 17,9 and 18,2 kg


Fin 672 gram
Elevator 908 gram
Right wing 2600gram
Left wing 2600 gram
tanks+hopper 450 gram
scale cockpit 415 gram
canopy 232 gram
thrustpipe 390 gram
duct 157 gram
Alu.tube for wing 288 gram

fuselage complete with powerbox, 2 powerbox Lipo's, powerbox display and switch, 3 valves(airpower/jettronics), airbottles (2 big and 3 small ), digital suquenser,switch for landinglights
7000 gram (+/- 100 gram)

Turbine complete 1896 gram (jetsmunt Merlin 160)

Regards
Ron
Nope, but I mounted a REAL engine
Anyway, just found my measurements some pages back:


ORIGINAL: cgroen

I just had the parts on a weight:

Fuse: 13.3 Kg (incl UAT, 125 mL)
Hor stabilizer: 0.8 Kg
Right wing: 2.5 Kg
Left wing: 2.5 Kg
Wingtube: 0.3 Kg
2 x Pilot/''bathtub'': 0.8 Kg

Total dry weight: 20.2 Kg
add 4.2 ltr fuel, weight 3.4 Kg

Total AUW is 23,5 Kg (approx 52 lbs)
This gives me 1:1 in thrust/weight right from takeoff, nice!
I have 800 gr more in the engine than a P160, and some heavy pilots in the seats, I have around 900 gr in batteries in the front (in the pockets besides the front leg), so guess that explains it (but I still have thrust-to-weight at 1:1 right at takeoff

BUT, even the "heavy" 23,5 Kg is nothing for the plane, I'm very impressed with how slow it can fly, it is soooo super easy to land (even for me )
Old 02-11-2010, 05:34 AM
  #890  
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Default RE: Another Skymaster Viper


ORIGINAL: DENTO


ORIGINAL: Ron v U

John / Carsten,

did you build in servo's with gears made of lead.
That is realy haevy.
The weight till now of my viper is : 17,6 kg(dry)
Only thing what needs to be done is build in 3 lipo's (turbine+landinglights) in the nose, to get the CG right.
Maybe when it's ready total weight dry between 17,9 and 18,2 kg


Fin 672 gram
Elevator 908 gram
Right wing 2600gram
Left wing 2600 gram
tanks+hopper 450 gram
scale cockpit 415 gram
canopy 232 gram
thrustpipe 390 gram
duct 157 gram
Alu.tube for wing 288 gram

fuselage complete with powerbox, 2 powerbox Lipo's, powerbox display and switch, 3 valves(airpower/jettronics), airbottles (2 big and 3 small ), digital suquenser,switch for landinglights
7000 gram (+/- 100 gram)

Turbine complete 1896 gram (jetsmunt Merlin 160)

Regards
Ron
BLINKY SCALES
Have a diferent set of scales, tanks full has come out the same 23kg so maybe 19 dry, Anyone,s guess, So go at that.
REGARDS
19 kg dry, that sounds better
Old 02-11-2010, 06:59 AM
  #891  
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Default RE: Another Skymaster Viper


ORIGINAL: DENTO


ORIGINAL: schroedm

23kg dry?! WOW!

I believe mine is 18.5kg dry, maybe 19kg with 160.

What do you have in yours to make up the extra 4 - 4.5kg!?!? [X(]
HI guys
I realy dont think I have any more in mine than what I see in whats being built, The scales were a set of commercials that my boys use in there business for postage so they
should be ok.but shall check again.Thanks for the replys.
REGARDS
JOHN

Hi John
Mine is 18.9 kilo to be exat with the new 160SX if you want me to way the wings and tailplane seperatly tell me and I will do it for you

Cheers Bronte

Old 02-11-2010, 11:24 AM
  #892  
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Default RE: Another Skymaster Viper


ORIGINAL: kimba


ORIGINAL: DENTO


ORIGINAL: schroedm

23kg dry?! WOW!

I believe mine is 18.5kg dry, maybe 19kg with 160.

What do you have in yours to make up the extra 4 - 4.5kg!?!? [X(]
HI guys
I realy dont think I have any more in mine than what I see in whats being built, The scales were a set of commercials that my boys use in there business for postage so they
should be ok.but shall check again.Thanks for the replys.
REGARDS
JOHN

Hi John
Mine is 18.9 kilo to be exat with the new 160SX if you want me to way the wings and tailplane seperatly tell me and I will do it for you

Cheers Bronte

HEY BRONTE
I was going to give you a ring today anyway, Two different Sets of scales, digital bathroom came out at about 19 dry,And as you seen in the post the boys use a set for there
freight so you would think they would be ok,Shall go back around to the factory reweigh this morning and settle this.
REGARDS
JOHN
Old 02-11-2010, 11:49 AM
  #893  
Ali
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Default RE: Another Skymaster Viper

Damn!!! That sounds like the set of scales I would like to use if I ran a freight company as was working out the charges
Heaviest we ever got a viper to was 42 lbs and that was with smoke, lights, pilots and some fuel on board!
Old 02-12-2010, 04:55 AM
  #894  
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Default RE: Another Skymaster Viper

GUESS WHATWEIGHT DIDN,T MEAN A THING.But fuel did, Dead sticked 5 mins into maiden flight but turned out ok,Shall try again on sunday.
REGARDS
JOHN
Old 02-12-2010, 10:23 AM
  #895  
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Default RE: Another Skymaster Viper

Glad you got it down ok John, any idea why it flamed out?


Dunc
Old 02-12-2010, 01:02 PM
  #896  
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ORIGINAL: Duncan

Glad you got it down ok John, any idea why it flamed out?


Dunc
G-DAY Duncan
Seam to think it may have been a leakey quick realease fitting I used on the kero fill, Top tank empty, bottom tank half empty, header tank empty,Seamed to think sucked air into the fill tube into the header tank while still getting fuel from the mains untill the header ran dry,Have replaced the valve with a festo and will do a runup and at the field and see what happens,For what time we had her in the air we were triming so didn,t get to get a full feel of her but the little bit was we did get was,
( WELL I STILL HAVE A FAT)
REGARDS
JOHN PS WILL LET YOU KNOW HOW WE GO.
Old 02-13-2010, 04:09 AM
  #897  
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Default RE: Another Skymaster Viper

Did the modification suggested by Ron and others to the vertical fin. I needed some way of detaching the fin without too much work (and without having to remove the thrustube )
My front pin on the vertical fin is made of carbon, the tube in the fuselage it slides into, is actually a brass tube, approx 1mm wall thickness, and with fiber/glue around it in the fuse.
As there is not much for the screw to "bite" in around the hole in the fuse, it is important to keep the screw relatively close to the edge of the fuse (more stabile), I drilled a 3 mm hole thru the fuse and carbon rod, and but a 4mm tap thru afterwards.
The screw sits very tight, and I don't think it will be possible for it to get out during flight.

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Old 02-13-2010, 05:41 AM
  #898  
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Default RE: Another Skymaster Viper


ORIGINAL: cgroen

Did the modification suggested by Ron and others to the vertical fin. I needed some way of detaching the fin without too much work (and without having to remove the thrustube )
My front pin on the vertical fin is made of carbon, the tube in the fuselage it slides into, is actually a brass tube, approx 1mm wall thickness, and with fiber/glue around it in the fuse.
As there is not much for the screw to ''bite'' in around the hole in the fuse, it is important to keep the screw relatively close to the edge of the fuse (more stabile), I drilled a 3 mm hole thru the fuse and carbon rod, and but a 4mm tap thru afterwards.
The screw sits very tight, and I don't think it will be possible for it to get out during flight.

Hi carsten,

Now you know you won't lose the vertical fin at all.
Is it not possible that the bolt will go complete into the fuselage.
I drilled that 5mm hole in the fuselage so the complete head of the bolt is also in the fuselage, but like i said, i have a lot of wood and glue overthere.

Regards Ron
Old 02-13-2010, 06:46 AM
  #899  
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Default RE: Another Skymaster Viper

Hi Ron,
yes, I would also like to have the head of the bolt go into a bigger hole in the fuse, but it is not possible on mine, as there is no "stuff" inside.
It's no big deal the head is on the outside of the fuselage, not much drag in it anyway, and I can always paint it green
Old 02-13-2010, 02:56 PM
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Default RE: Another Skymaster Viper

I did a similar mod. My fin had a 2mm gap at the front when it was in place

Do I did it the hard way - cut off the carbon rod , and drilled it out as good as possible. (very hard carbon that is!! Cost me a few drills)
Turned a new alu pin (with grooves for the glue to hold on) on the lathe, and glued in place. Now it fits like a glove, and I drilled a small hole in the same way you guys did - M3 thread in the alu, and the fin is now really tight. (Don't think I would have lost it without the screw, but this is extra security)


Hans

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