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Taft Hobby EPO Viperjet, 90mm EDF/micro turbine *Video*

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Taft Hobby EPO Viperjet, 90mm EDF/micro turbine *Video*

Old 10-07-2013, 05:11 AM
  #51  
marc s
 
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Think its why Gasper is taking his time to make sure all is good. Some of the small airframes you would be please to not have to find a place for values!

marcs
Old 10-08-2013, 04:48 AM
  #52  
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Originally Posted by Henke Torphammar
I'm just converting my Viperjet with tamjets struts and the electro breaks (with turbine I need them to ever stop)

I use the Super Sniper struts which are disassembled to be shortend by about 1/2". One of the main wheels became the new nose wheel and the larger ready2fly breaked wheels will be the new mains.





the axle of tamjets strut where is inserted the wheel measure? 3-4-5mm?
Old 10-08-2013, 04:59 AM
  #53  
Henke Torphammar
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It depends on what you orderd from Tamjets, check his site for info. If I remember correctly the struts I got were for 4mm wheel axle and 4mm pin, but imperial screws.
Old 10-08-2013, 05:08 AM
  #54  
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in the tamjets website there are 2 kind of strut, if you check, 1 is for super sniper, 1 is for viper, check, this is the 2 link, what is correctly to useon viperjet?

http://www.tamjets.com/original/prod...31ccd3df75f2e0

http://www.tamjets.com/original/prod...31ccd3df75f2e0
Old 10-08-2013, 07:24 AM
  #55  
Henke Torphammar
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Originally Posted by sim76
in the tamjets website there are 2 kind of strut, if you check, 1 is for super sniper, 1 is for viper, check, this is the 2 link, what is correctly to useon viperjet?

http://www.tamjets.com/original/prod...31ccd3df75f2e0

http://www.tamjets.com/original/prod...31ccd3df75f2e0

The links won't work here. I use struts that are not for the viperjet as I wanted the real trailing link. If I remember right it was for the Sniper.
Old 10-09-2013, 12:06 PM
  #56  
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I have a Viper on order from Hobby People, what Battery do you guys recommend..?? Is a 6S, 40--45C okay as I have a new one, or do I need to shoot for a 60-65C..?? The Viper will be stock with no mods anticipated at this time.

Any other concerns such as servos, EDF, or any other issues? This one is a PnP version just needing a radio...
Old 10-09-2013, 12:09 PM
  #57  
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I'm using a 35 and a 45C battery, both 6S

Mine is completely stock

Last edited by bcovish; 10-09-2013 at 01:23 PM.
Old 10-09-2013, 01:16 PM
  #58  
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Dreamworks has them on there website for $469.
Old 10-09-2013, 01:40 PM
  #59  
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Prop wash. I have flown mine on gens ace 50c 6s 5300mah. Gives about 4 min of mixed flying with 20-25% left in the pack. I have tried nanotech 60-130c with similar results. ( although I will say I killed one of my nanotech packs. could be coincidence as I use these in my trex 700dfc and 800 trekker also) Higher C normally gives better internal resistance numbers over the cycles. Nanotechs seem to puff more than pulse or gensace as well. Moral to story, don't skimp on batteries. Get the best you can afford.
Old 10-09-2013, 01:46 PM
  #60  
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Originally Posted by bcovish
Dreamworks has them on there website for $469.
Thanks for posting, just ordered it
Old 10-09-2013, 04:03 PM
  #61  
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Originally Posted by bcovish
Dreamworks has them on there website for $469.
I saw them on their site but the S&H was $80.00 or so... so I went with Hobby People $519.00 shipped...

Castle version didn't have the motor for the EDF...
Old 10-09-2013, 04:06 PM
  #62  
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Are the stock Servos, ESC, EDF and distribution board okay..?? Anyone getting over 100 flights out of the stock hardware..??
Old 10-09-2013, 09:25 PM
  #63  
Henke Torphammar
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If you get 4min flight times and your battery supplier are telling the truth you would do perfect with cells rated 15C, with 30C peak(!) But I know, the real word is diffrent. If higher C cells would only cost more $$ things would have been fine, but they cost in weight and life span too. Heavier with much shorter life.

10 years ago we set up our planes to fly for 15-20min as the batteries only allowed that. This made the setup easier on motor and batteries. You also needed to think twice before buying a setup as you needed parts that work well togeather. Now days we lost all sense of what's working and you press buy on the hobbyking site adding higher C cells to compensate. hm... back then you did't even need to balance the cells.

Most tend to like the stock servos, but have problems with the board. I always buy the kit and install HS65MG servos in my foamies, I feel safer that way.


my TP yellow label over 9 years old and never charged.

Old 10-10-2013, 03:38 AM
  #64  
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Originally Posted by Prop_Washer2
I saw them on their site but the S&H was $80.00 or so... so I went with Hobby People $519.00 shipped...

Castle version didn't have the motor for the EDF...
Shipping to NY from Dreamworks was $30.22, making my total $500.21 Shipped.
I went with the E-flite 5000 6S, although I've never used an e-flite pack before, they seem to put out good stuff.
Henke, did you need to mix any aiel/elev to get her to knife straight?
Jay

Last edited by BlueBus320; 10-10-2013 at 03:44 AM.
Old 10-10-2013, 04:20 AM
  #65  
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Higher c battery has a much higher voltage under load which allows you to get the same power at lower throttle and fly longer. It's like using a bigger turbine and throttling back. With a higher c battery you are not at full throttle as long so the flight times are longer. A 50-65c is totally different than a 15c, especially in an edf that requires a lot of power.

Originally Posted by Henke Torphammar
If you get 4min flight times and your battery supplier are telling the truth you would do perfect with cells rated 15C, with 30C peak(!) But I know, the real word is diffrent. If higher C cells would only cost more $$ things would have been fine, but they cost in weight and life span too. Heavier with much shorter life.
-
10 years ago we set up our planes to fly for 15-20min as the batteries only allowed that. This made the setup easier on motor and batteries. You also needed to think twice before buying a setup as you needed parts that work well togeather. Now days we lost all sense of what's working and you press buy on the hobbyking site adding higher C cells to compensate. hm... back then you did't even need to balance the cells.

Most tend to like the stock servos, but have problems with the board. I always buy the kit and install HS65MG servos in my foamies, I feel safer that way.


my TP yellow label over 9 years old and never charged.

Old 10-10-2013, 04:55 AM
  #66  
Henke Torphammar
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Originally Posted by TUMBLER
A 50-65c is totally different than a 15c, especially in an edf that requires a lot of power.
The problem is that the hyped 65C battery infact is a true 15C
Old 10-10-2013, 04:56 AM
  #67  
Henke Torphammar
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Originally Posted by BlueBus320
Henke, did you need to mix any aiel/elev to get her to knife straight?
Jay
It needed very little mixing. If I remember right it was a 7% down mix on rudder. Just fly and try it
Old 10-10-2013, 05:30 AM
  #68  
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I have serial # 0003 PNP all stock parts have been working great it even takes off from short wet grass. Radius the intakes which are sharp edges helps the vertical. My batteries and speed control are puppy warm after full throttle

flights. Lands best with half flaps. Flaps (1/2) are a must for grass takoffs.
Old 10-10-2013, 08:04 AM
  #69  
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So gentlemen I see we have a turbine powered jet many want to ban for structural reasons and now we have a foam constructed jet with a turbine installed. I was under the impression that heat and foam are not good bed fellows. This combination in my opinion is a disaster waiting to happen.
Old 10-10-2013, 08:10 AM
  #70  
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Goodbye flycatch. Go troll another thread
Old 10-10-2013, 09:28 AM
  #71  
Henke Torphammar
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Originally Posted by flycatch
So gentlemen I see we have a turbine powered jet many want to ban for structural reasons and now we have a foam constructed jet with a turbine installed. I was under the impression that heat and foam are not good bed fellows. This combination in my opinion is a disaster waiting to happen.
Someone not knowing better always guesses a tubine is hot, which it really isn't. You always get the question "How high can you fly?" "how far away can you fly?" "how fast can you go?" But you never ever get a question "is the turbine hot?" as everybody know it is hot... or atleast they think so. In fact about 90% of the air used by the turbine is for cooling(!) and they are pretty cool. Now how do I know this? Because I have tested it. Testing is knowing

A Kolibri running at full power looks like this


Idle


Either you back mount or center monut the turbine, while ruinning you get a venturi effect keeping things well below the critical temp of the structure. I really think heat would be a greater problem in the fiber glass models then the foamies.
Old 10-10-2013, 09:49 AM
  #72  
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Thank you, for addressing my post however a jet turbine does have a combustion chamber which is evident in your pictures. This chamber does generate heat in a closed environment and the flash point for EPO foam is very low. How long would it take for the area subjected to this heat loose its structural integrity. Can it be measured that I can't say however the possibility does exist.
Old 10-10-2013, 09:50 AM
  #73  
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So I'm a troll because I raise a question based upon reality.
Old 10-10-2013, 10:09 AM
  #74  
Henke Torphammar
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Originally Posted by flycatch
Thank you, for addressing my post however a jet turbine does have a combustion chamber which is evident in your pictures. This chamber does generate heat in a closed environment and the flash point for EPO foam is very low. How long would it take for the area subjected to this heat loose its structural integrity. Can it be measured that I can't say however the possibility does exist.
I'm not with you there. The hot exhausts are not in contact with the foam. Either you let them out behind the plane via a thurst tube or directly if the turbine are back mounted. Heat simply is not an issue. However a turbine makes ALOT of more power then the EDF setup. There fore not every foam plane are suited for turbine use. This Viperjet does fine though
Old 10-10-2013, 10:53 AM
  #75  
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The key here is... you draw in "Cooling air" to protect the parts. If Henke set up is pipe properly... And I'm sure he did.... the venturi effect will draw cool air around the engine, and in turn... the foam never "Sees" the hot engine, or exhaust temps.

I have a little crappy T-45 that was meant for an EDF system... but I stuffed in a MW44, and I use a simple single wall pipe. Every event I go it... guys ask.... "Doesn't that get hot?" my answer is always "No, it doesn't." I still get a few guys who don't really believe me, so I start it up, and after 2 or 3 min of idling... the top of the fuse is still cool.

Last edited by Dr Honda; 10-10-2013 at 10:56 AM.

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