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Apr 06, 2020, 01:22 PM
Dont confuse me with the facts
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This is for par, he is going to print the inlet adapter for the modded Dynamax Fan.

Scott
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Apr 06, 2020, 07:39 PM
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What do you think? 22g
Apr 06, 2020, 07:51 PM
Dont confuse me with the facts
Thread OP
I will take two. One like that, And another one that has 25mm added to the part after the Dynamax diam and before the lip.

Scott
Apr 06, 2020, 09:57 PM
BFMA #13, aka Rogue 13
mongo's Avatar
while everyone is talking esc...

https://www.rcgroups.com/forums/show...-YGE-320hv-esc

kinda surprised it has not sold.



this was suposed to have been posted in the e-dynamax thread.
sorry folks.
Last edited by mongo; Apr 07, 2020 at 12:18 PM.
Apr 09, 2020, 07:44 AM
Registered User
Scott,

Can you verify the dimensions one last time for me?
Apr 09, 2020, 11:31 AM
Dont confuse me with the facts
Thread OP
Yes, I will go with both of those. If the shorter one causes separation than I will use the longer one. If not, than the two will allow for batt and CG placement. I will also take a bell mouthed or 1/2 circled intake lip of your design if your up for it. It would simply be used in testing the separation of the other two.

Thanks,
Scott
Apr 09, 2020, 06:56 PM
Dont confuse me with the facts
Thread OP
Pictures of the EDFs going in the extended wing UV.

The Jetfan v2 700-75-1250 on 12S 5400 Watts with CC 12S ESC fits well with the existing turbine inlets.
It weighs 736.8 not counting batts making 14 Lb thrust. But can it go off of grass?

The BVM EVF 4410 on 10S 4500 Watts will give more thrust and I will have to change the inlets, it can also do 12S.
It weighs 1106.7 grams. 16-18Lb thrust using 10S-12S.

I am not sur wich I am going with, so I am showing both.

Scott
Last edited by Scottfpv; Apr 09, 2020 at 07:37 PM.
Apr 09, 2020, 07:17 PM
Dont confuse me with the facts
Thread OP
EDFs going into the faster of the two UVs with stock wingspan.

BVM modded EVF~3~16S 7 blade (it still says 14S) for 25Lb thrust 8800 Watts. Modded to have higher kv and lighter than stock.
Weighs 1054.6 grams. This goes in UV with stock wings (yellow).

Second EDF is a Parfan 22S(it will be running on 23S 4.34V) for 35+Lb thrust 15,000 Watts.
Weighs 1895.3 grams plus ESC is about 2095 grams. This goes in the kit UV with internal linkages. We will have to build her light to compensate for the weight of the motor. We are testing another motor now to shave weight, but we are not going to compromise on power.

Scott
Apr 09, 2020, 08:05 PM
Registered User
The fan looks good, but the "back-cone" looks much less "air flow friendly" with all the cooling intakes and bigger than the BVM design. Is it just an illusion ?
Apr 09, 2020, 10:11 PM
Dont confuse me with the facts
Thread OP
Quote:
Originally Posted by vasek
The fan looks good, but the "back-cone" looks much less "air flow friendly" with all the cooling intakes and bigger than the BVM design. Is it just an illusion ?
Well, the answer to your question depends on your point of view. It is true that the Parfan fairing grabs more air from behind the fan. So it is designed to let more air flow back through the motor. Behind he motor, air flows in reverse of the stream. Par used it to cool the motor to get more reliable power. Bob tried to prevent that and get air in to cool the inboard ESC for an all in one unit.

Different priorities. Par wanted to show people how to build the most powerful reliable EDF in this size period. Going hard core on the motor cooling. This thing can run 15000 Watts for 2min strate. Bob wanted a patented all in one reliable solution for customers. I respect both ideologies, but they can be seen in the design. IMHO!

As far as an optical illusion is concerned, perhaps these pictures will help you answer that yourself.

Scott
Last edited by Scottfpv; Apr 09, 2020 at 10:41 PM.
Apr 09, 2020, 11:56 PM
Registered User
Scott, I see your point. And actually, in the side-by-side pics the size dif. is not that bad. It looked worst in the previous pics.
Don't forget to post a vid in flight. I like power !
Apr 10, 2020, 02:54 PM
Dont confuse me with the facts
Thread OP
Vasek, do you have any pictures of your UV that you would like to share? Any details on your pictures, build, decision making process, and final product would be appreciated.

Scott
Apr 10, 2020, 06:50 PM
Registered User
Scott, I will look for some pics. I am in Canada and the UV is in Europe. I checked my laptop, so far
no luck. But I posted some of my build on various UV threads (RCU and RCG) the last 10 years!
Yes I've been working on it on and off that long. I bought it about 15 years ago on RCU from a fella here in Canada. I drove 1/2 way 500 Km to pic it up. The chap I bought it from was not 100% honest and the transaction took place in a parking lot half way... so there were some major issues with the 1/2 build UV. It started as a DF with BVM .91 engine and now I have the BVM EVF V2. I had to redo the "wavy trailing edges with epoxy, put Carbon rods in the fin to straighten it and so on. It's almost done now, I'm in the painting phase . Here's what I've learned over the years:
It's been designed to go fast on a limited .91 power in a straight line (most of the time). The Electra was build from the UV design to adopt a better flying envelope using more powerful EVF thus the wings are "longer" and have flaps. Some people added flaps to the original UV wing, which I would not recommend unless the wing is "extended". With the original UV wing, the flaperons work, but it's not ideal setup. There was an early "option" with a "speed brake" under the belly (see attached). That works very well slowing the jet for landing, and the flaperons could thus have less deflection and eliminate the "mushy" aileron feel on landing configuration.
Also on the original UV wing, I'd recommend droops to help with slow flight if heavier. That works well. I have BVM brakes and wheels, but the wheels don't fit, you have to "lathe sand" the tires down a bit. And they're quite heavy. JP Hobby 55mm wheels and brakes is the way to go on this (see pic). If you fly off grass, no brakes needed . Also see the Rx setup I have. If you have questions...
Apr 10, 2020, 07:56 PM
Registered User

Paint scheme


I found my pant scheme layout
Apr 10, 2020, 08:56 PM
Registered User
found some more files:

bottom view my pait scheme; speed-brake better view (not mine); BVM droops install on a Maverick (same principal as on UV)


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