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Archive for May, 2015
Posted by PeterVRC | May 19, 2015 @ 07:13 PM | 10,379 Views
I have had this jet a LONG time now! It was my first 70mm EDF jet!
I actually have two of them....

Mine are Version 1's, but be sure to get the Version 2 if you buy one! They now come WITH retracts. I had to modify mine to have retracts - though I guess I got to do what I wanted and make it truly robust.

Hmmm, it looks like a HABU !! I guess it is a clone of that excellent flying jet, and thus why this one is excellent too!
It is totally fine to fly it as it comes in its 4S guise.
Or upgrade the ESC (only) to 90Amps so you can run the stock plane on 5S - which stresses the motor but MOST people have had theirs cope with that. Some go up in smoke....
Or change the whole fan combo to a higher Power setup. 1000W.... 1200W... 1300W... 4S, 5S, 6S.... CS10, 12, 14... Wemo EVO, Pro...

It is a very sleek jet, which means it can fly fast! Like a missile - though not so fast on the stock 4S setup. Still fast though!

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Posted by PeterVRC | May 07, 2015 @ 06:25 PM | 9,464 Views
After having bought all kinds of CHEAPER bits for EDFs and building up a bit of everything you can do that way, I decided to get an ExtremeRC ready to run combo.
I could still have done that the same myself, but it is not much more to have it all done and ready to use so I figured I would do that to check it out.....

The ERC Jetfan combo choices are here:
http://www.extremerc.com.au/estore/i...ath=146_11_375

I wanted something above 'average' in power, so I chose the 8S 3000W combo - you can always use lower Throttle! hehe

I actually already have two Jetfan Rotors and Wemo EVO Rotors, but have not assembled those because getting a suitable CHEAP motor is not easy/possible.
The HK Fandrive 3968-1500kv CHEAP BEAST ($74) is a really great motor... but it has an 8mm shaft which Jetfans and EVO's cannot fit! BAH.
A suitable HET motor costs $160

The ERC specs for this combo are:
29.58v / 101A / 2990w / 4.5+kg thrust (1.52 Thrust to Power)
And there is a video to show/prove that!!
Those are good numbers!! This shows the motor is coping with that load just fine.

When I set mine up and tested it I got:
28.1V 93.6A 2620W 4.00Kg - using 2x 4S 4400mAH 65C Turnigy Nanotech (also 1.52 Thrust to Power)
But you can see the VOLTS dropped a lot - the battery cannot do that load comfortably!
These numbers also show that the ERC numbers ARE in line with what you would get if you had a better battery.

Once in a jet, with reasonably decent ducting, you should get 1.3x to 1.4x the WATTS in Thrust. So mine at 2600W = 3.38Kg to 3.64Kg. Which should be the upper region of a jet's AUW for that anyway. WAY more Thrust than you truly need in most cases! But you do 'need' a lot if you want your scale jet to also be able to do a scale TOP speed!

Note this test below is using Revo batteries, but the HK Nanotechs (plain Nano) can drive the combo to another 200g higher Thrust. For almost 4 Amps more input.
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Jetfan-HET, HET650-1600kv 8S 4400mAH 60C Revo 90.6A 27.4V 2470W 3.87Kg (1 min 5 sec)