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CARF Ultra Flash Evo build thread +

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CARF Ultra Flash Evo build thread +

Old 07-27-2022, 07:20 AM
  #376  
jvaliensi
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Dave uses JetCat turbines and they have very low residual thrust, especially the P100-Rx. That helps.
I have a new UF Evo to fly too.
Old 07-28-2022, 10:48 AM
  #377  
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Originally Posted by Dave Wilshere View Post
Won’t stop it on an UF, the curved tips do that. It just changes the AOA and dumps lift.
I can land at walking pace with a std set up.
Thank you for your help
Rocco
Old 07-28-2022, 11:19 AM
  #378  
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Default Batteries

Originally Posted by jvaliensi View Post
Hullo,
It is clear the Ultra Flash needs significant weight in the nose. I would like to place the batteries in front of the nose gear, but that area is nearly in accessible. It would be a pain to remove the batteries for charging.
I could charge the batteries in the airplane, but this seems risky.
How are others installing batteries?

Thank you


This is where I put them.
Old 07-28-2022, 11:28 AM
  #379  
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I was worried about being tail heavy with my build, and ended up so nose heavy that I moved my batteries back near the turbine.
Old 07-28-2022, 11:32 AM
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Originally Posted by jvaliensi View Post
I was worried about being tail heavy with my build, and ended up so nose heavy that I moved my batteries back near the turbine.
i was nose heavy also but all my stuff was in place so I put 2oz of lead in the tail to get 230
Old 07-28-2022, 12:38 PM
  #381  
Dave Wilshere
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Not surprised you are nose heavy with your equipment choice, did you have some fuel in the main tank when you balanced it? If not you will need more tail weight.
Old 07-28-2022, 01:01 PM
  #382  
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Default CG

1” of fuel in the main tank
Old 07-28-2022, 08:50 PM
  #383  
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OK, it will be close. What I’m seeing with the Evo tank is the balance moves forward with a full tank because of the shape, so depending on the pilots requirements, it can go back a little more.

Dave
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Old 07-31-2022, 12:19 PM
  #384  
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Hi,
I am looking for a pilot exactly like the one Dave Wilshere used. I cannot find one, most options seem out of stock.
Please let me know if anyone has one or knows of where to get one.

Thank you!
Old 08-01-2022, 01:24 AM
  #385  
Dave Wilshere
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Mine.


Old 08-01-2022, 06:25 AM
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Originally Posted by Dave Wilshere View Post
OK, it will be close. What I’m seeing with the Evo tank is the balance moves forward with a full tank because of the shape, so depending on the pilots requirements, it can go back a little more.

Dave
These are my findings with a Xicoy CG meter on the Ultra Flash Evor:
Fuel in the tank does not change CG until it reaches the flat part of the tank which is when you start seeing the fuel. The CG will move forward a total of 5mm as you fill the tank to full. Also I noticed with CG at 230 and with only the UAT full and the jet resting on it’s tail it will barely stay there without the nose coming back down.
Hope this helps someone.

Rocco

Last edited by traxxis1; 08-01-2022 at 06:34 AM.
Old 08-01-2022, 09:25 PM
  #387  
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I was going to order the CMJets tanks but decided to give Jet-Tech a try since they are made here in the US. I got them the other day and wow are they nice! I got the main EVO tank and the wing tank to use for smoke.

I also got my Electron retracts… just about have all the parts but now getting ready to sell the house and move so it will be a little while before I can actually start on my UF.

Old 08-02-2022, 07:14 PM
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My batteries and ECU battery are right at the front of the nose section, that's strange you had to move them aft.
Old 08-02-2022, 09:15 PM
  #389  
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Metal case servos in tail? There can be lots of reasons
Old 09-12-2022, 02:35 PM
  #390  
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Anybody use this pilot before in the UF?

https://dreamworksrc.com/product/sd-...ot-4-17-scale/
Old 09-12-2022, 03:10 PM
  #391  
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camss69,

Yes, it's an appropriate size. I paired it with the top half of an old Skymaster Hawk ejection seat.

Paul
Old 09-12-2022, 07:18 PM
  #392  
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Originally Posted by JSF-TC View Post
camss69,

Yes, it's an appropriate size. I paired it with the top half of an old Skymaster Hawk ejection seat.

Paul
Awesome, thanks, I ordered him.

How about the quick disconnect for the wing tank? What is the most reliable thing to use?
Old 09-12-2022, 07:24 PM
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I used this self sealing quick disconnect for my wing smoke tank. Worked great.

https://thunderboltrc.com/index.php?...oducts_id=1299

Unfortunately they are marked as sold out, but should give you an idea.


Paul
Old 09-12-2022, 08:55 PM
  #394  
Dave Wilshere
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I use a Festo 6-6 Ball Valve as the joiner, so I can shut it off in storage
Old 09-13-2022, 04:58 AM
  #395  
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I and others have good success with Kent System connectors for fuel lines. Post #136 has the part numbers:

Foamie jet for X45/K45 ?



Old 09-13-2022, 07:37 AM
  #396  
Dansy
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I think the Festo ball is the best idea…..Kent fitting are not sealed, but they do have plug for them…..a simple festo fitting with a plug would also work fine.
Old 09-13-2022, 08:08 AM
  #397  
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I use the Kent fittings with a built-in ball valve. Gives me drip-free fueling. But I do plug them (both the model tank and fuel station).
I use Fesco too. But the Kent system is designed to be disconnect often and is much easier to do so. And they are very light weight. When they start to wear out, I'll replace with new, as they are much cheaper than Fesco's.
Old 09-15-2022, 04:48 AM
  #398  
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I finally received my Ultra Flash. I am a little surprised the manual has not been updated since 2010. It is pretty much useless but I've built enough that I can figure it out. Hopefully the CG is correct.
Old 09-15-2022, 10:51 AM
  #399  
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Yes ......the carf manuals leave a lot to be desired
Old 09-15-2022, 01:16 PM
  #400  
Dave Wilshere
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Balance it with a good amount of fuel. Set up is all std UF since that’s what it is.

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