[paulj]

Steve, you may have seen in my F14 thread that I'm thinking
of converting it from a pusher prop to twin ducted fans.
I would be limited in what I can put in there to at best 55mm fans.
Think this is what you had in your A10 isn't it?
How did you find them? Did they have enough power for the A10?
Looking at GWS 55 Ducted Fans and KB20-40-12 Brushless Inrunners (4800Kv)
from Hobby King do you have any knowledge of them?
Any comments from anyone else would be greatly appreciated also as I don't
know much about EDF's.
Also Steve, what size batteries did you use with the A10 and did you use 2 batteries per flight?

Paul

[samste]

Gday Paul

I had 55mm edfs in A10 link below of motor and edf55, though when i got mine they only had 64mm edfs and i had to swap out and fit to 55mm edf's
link to 55mm 5250kv
http://www.fmhobbies.com/servlet/the-28 ... 5mm/Detail

link to 55mm 4100kv
http://www.fmhobbies.com/servlet/the-28 ... 5mm/Detail

Though i think you may be better off with the 55mm edf 4100kv if you are going to use two as my A10 had way too much grunt.
(Less amps too with lower Kv)

Specs A-10 approx where -
3000ma 3s lio 35c
5250kv 55mm edfs each with its own 50 amp esc
730 grams thrust approx on each edf giving it a total of 1.4 kg plus thrust
The A-10 only weighed 980 grams with battery giving it a lot of power.(about 500gms of thrust over the weight)
approx 4 min flight time.

My Jetiger screams at only about 140gms of thrust over the weight and today i gave it full throttle and it was doing speed verticals.
approx 4min flight time with 1800ma 14.8v lipo 40c

Hobbyking has something made up already but not confirmed specs an suggests 14.8v but you would only be using one only if possible,
http://www.hobbyking.com/hobbyking/stor ... oduct=5483
Amps is not your Friend when it comes to EDF's As i Have learned With My Projects sonic saber, A-10 and Jetiger.
The way i did my calc's where as long as i had more thrust than the weight of complete plane including battery it was going to fly,
the more thrust above the weight the more grunt i had in hand


Caution though when testing stanalone edf's (not mounted in plane) by holding with hands above scales, some edfs are flimsy and you could squeese to hard and blades will hit side of edf and break.

Steve

[paulj]

Great info as always Steve thanks.
Will do a bit more research on this but in the meantime I
can continue on with my build.
Lucky that the modifications required for edf will also work
for the pusher prop so it won't hold me up too much.
Interested that you thought that the A10 had too much power
as I always thought that you could not have such a thing.
What made you think that? Was it making the A10 difficult
to fly?

Paul

[paulj]

Somemore advice required please.

Looking at the specs of the GWS 55mm Fans it shows the Inlet end of the fan
as 68.4 mm.
Just a bit too big to fit inside the F14 Engine Inlets.
Question, Can the front of the fan be easily removed?
Thinking of using some scrap Depron to make a mount to hold the fan cylinders inside
the Inlets.
Looking at the drawings on the web the front is fitted on to the outside of the 55mm
cylinder which houses the fan and motor.
If I can't fit these in that way I will have to look at using Wemotec Micro Fans which are not
available from HK and will considerably add to the cost of the edf setup.

Paul

[~KevJ~]

hey steve have you currently got any 55mm fans at home not mounted to anything :?: dad it would be good if steve could bring one down to the field to have a look at and get some real world measurements to confirm if they will fit.. :idea: :ugeek:

[samste]

I do have a few Edf's i can bring down on Saturday for Paul to Try Fits' etc, unless your down on Thursday arvo Paul for a fly.
Though i had my great Fix Today far far away and loved it so much,
viewtopic.php?f=1&t=22&p=1813#p1813

[paulj]

Thanks Steve that would be great.
Don't think I can make it on Thursday or Saturday.
Are you planing on going down Sunday too?
Really mixed up about what I'm going to do with the F14, I'll
explain on the F14 thread.

Paul