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Old Oct 13, 2014, 07:25 PM
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United States, NM, Clovis
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Those numbers sound good... What flight time are you getting naryan?
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Old Oct 13, 2014, 07:55 PM
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United States, VA, Leesburg
Joined Dec 2008
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Originally Posted by DamonH View Post
Those numbers sound good... What flight time are you getting naryan?
On a really hot flight with a lot of full throttle passes and climbs I've been flying 3.5min and the packs are at 3.78-3.8v per cell. I've flown a few other flights with more conservative use of the throttle, and stayed up 4.5min and the cells were still ~3.85v.

Next time I make it out I'll try to get a video of two different flights for comparison sake.
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Old Oct 13, 2014, 08:10 PM
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On 8s I am getting 31/2mins &10s ....4mins...on 4000mah ...coming down with 3.8V per cell...probably 1/2min more each if coming down with 3.65 per cell...Beauty about 10s is 1/2 throttle still motors along very nicely....Love fast passes & then inverted vertical roll on 10s. On 8s it's no slouch either.... The Jetfan/Wemo Evo are very efficient depending on motor selection & throttle control ( what's that ??? ). On my Stinger 90 I have a Wemo Evo with a 1350kv motor solely for 10s...it draws a meagre 72 amps...get 41/2 mins...
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Old Oct 15, 2014, 08:15 AM
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Italy
Joined Oct 2004
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Hello my new Viper is arrived!! I have some questions since it is my first jet EDF:

1- What are the optimal surfaces throw?
2- what is the right deflection for flaps?
3- The doors of landing gears has some gaps when closed is it normal? there is a way to add some more throw to the servos? how does the sequencer work?


I read that the right cog is at 105mm is it right?
I will use stock electronics with 6s 5000mah lipos.

Let me know if some mods or tips are need.

Thanks
Adriano
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Old Oct 15, 2014, 09:45 AM
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United States, CA, Sunnyvale
Joined Jul 2008
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Quote:
Originally Posted by uragano47812 View Post
Hello my new Viper is arrived!! I have some questions since it is my first jet EDF:

1- What are the optimal surfaces throw?
2- what is the right deflection for flaps?
3- The doors of landing gears has some gaps when closed is it normal? there is a way to add some more throw to the servos? how does the sequencer work?


I read that the right cog is at 105mm is it right?
I will use stock electronics with 6s 5000mah lipos.

Let me know if some mods or tips are need.

Thanks
Adriano
1- 3/4" high rate, 1/2 mid rate, 3/8 low rate 25% expo all around
2- as much as you can go with out the servos buzzing like crazy---no elevator mix needed.Dont put down flap going over 1/2 throttle
3- you can turn the ball links inward on the rod to close them up more.
sequencer works as follows
gear up switch -- main doors open, gear in, doors all close
gear down - all doors open, gear out, main doors close

yours may not have the main doors close and open...mine did..I have seen some that dont
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Old Oct 15, 2014, 10:40 PM
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United States, TX, Houston
Joined Mar 2014
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Quote:
Originally Posted by uragano47812 View Post
Let me know if some mods or tips are need.

Thanks
Adriano
Locktite al screws and tape all hinges
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Old Oct 16, 2014, 09:27 AM
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United States, GA
Joined Sep 2013
109 Posts
Struts

Is anyone using the Tamjets struts on the viper and retaining all the gear doors? I would like to install the Tamjets struts on mine but I don't want to loose the doors. Which version of the Tamjets struts is everyone using? Thanks. Brian
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Old Oct 19, 2014, 07:05 PM
Watt me worry?
Madmax1965's Avatar
Florida
Joined Mar 2006
3,996 Posts
Brian I installed the Tams trailing links on mine but the doors didn't fit so I am flying without them. You must cut out some of the wheelwells when using the trailing type. Read back in the thread I think someone did figure a way to do a fix. I can't speak for the regular Tams struts...just the trailing type. I do like the trailing links as the plane settles nicely on landing.

By the way if anyone is flying a Stinger 90 there is a canopy/cockpit upgrade which was released just minutes ago.
http://parkflyerplastics.com/cart/in...roducts_id=711

Be aware there are up-grades for Stinger 64 and Stinger 90........don't order wrong one
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Last edited by Madmax1965; Oct 19, 2014 at 08:44 PM.
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Old Oct 19, 2014, 07:43 PM
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United States, CA, Milpitas
Joined Jul 2008
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Hey thanks for that I will definitely pick one of those up.
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Old Oct 19, 2014, 08:22 PM
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United States, UT, Saratoga Springs
Joined Mar 2010
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On a side note, I raced my stock 8s Viper Jet against a stock 6s Stinger 90 and we were pretty well dead even when flat & level. Did 2 flights and with both planes at full speed down the runway neither could get ahead of the other.

I was pleased because the Stinger "looks" faster when it is flying alone, due to the smaller size I suppose. The VJ is bigger and looks a bit slower when flying alone.

Anyway, the two were pretty well the same speed in a drag race.

Also, the Stinger had been previously clocked at 106mph. I'm good with that for my VJ. Flyers at lower altitude may do even better. We are at 4500 ft here.

Justin
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Old Oct 20, 2014, 08:49 AM
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United States, VA, Leesburg
Joined Dec 2008
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Quote:
Originally Posted by Madmax1965 View Post
Brian I installed the Tams trailing links on mine but the doors didn't fit so I am flying without them. You must cut out some of the wheelwells when using the trailing type.
You are using the HET Super Sniper struts correct?



The JT Viper Jet Struts from TamJets can be used with the doors if you are using the stock wheels. Just email Tam and he will make them a bit shorter for you so you can use them with the Taft ViperJet.

http://www.tamjets.com/original/prod...roducts_id=640

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Old Oct 20, 2014, 04:34 PM
Watt me worry?
Madmax1965's Avatar
Florida
Joined Mar 2006
3,996 Posts
I don't remember if they were the Sniper struts but they look the same as the ones I used.
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Old Oct 20, 2014, 10:06 PM
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United States, GA
Joined Sep 2013
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I love the struts and I know they work well but I sure do want to keep my doors intact. Lol. If I knew I could buy some that would retain the doors I would be all over it. May just have to contact Tam. Thanks
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Old Oct 21, 2014, 11:02 PM
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Joined Jan 2013
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Quote:
Originally Posted by techspy View Post
If you find it getting too warm, add a couple naca ducts like I did. I got them from parkflyerplastics.com. I found that even with the grate on top there was a lot of airflow still going into them.

I will be doing the same thing on my new one.
Page 119 for pics.

How is this working out? Is the bottom opening just for cooling or does the fan need the extra air? Does this change the sound? Better? Worse? Does this help takeoff with the jet being sucked up instead of down? Does it fly different? I am going to plug the hole where the front wires come through. A bit of grass tries to get in that way too. I am using the suggested screen on the bottom and that works great.
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Old Oct 22, 2014, 11:23 AM
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Joined Jan 2013
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Found this: http://www.rcuniverse.com/forum/rc-j...ine-video.html
Scroll down for Tam strut photos. Two styles.

And this: http://www.rcgroups.com/forums/showt...91131&page=227

Another: http://www.rcgroups.com/forums/showp...postcount=3272
Page 219
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Last edited by 9Mach; Oct 22, 2014 at 11:46 AM.
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