69mm or 70mm EDF

[sihinch]

Asking EDF experts - what's a good 70mm EDF fan unit and motor for 4S?  I'm looking for around 600 watts.

I was wondering about the E-Flite Delta V 15 and the 3200kv motor that's found in the Habu.  But I also thought that Jeff might have some ideas???

Thanks,
Simon

[flying saucer]

You can go with a 70mm eflite fan and 3200kv motor from a Habu, but this will give you more like 950watts and 60amps (and that annoying high pitched EDF drone

Or you can go with the Changesun fans me and Ronny run. For the kind of power you are looking for a Turnigy L2855 2300kv motor on 4S will do the trick, and still give you very decent thrust.

If you can wait awhile (4S version) your best bet might be one of these:

HobbyKing Daily - Turnigy Aluminium EDF Unit

I'm currently running the 6S version in the Panther. The only drawback is weight, these alloy fans are quite heavy...

[thehaze]

Those HK units look promising. The 4S version should be a top seller when it arrives.

[flying saucer]

Get 'em while their hot..

http://www.hobbyking.com/hobbyking/store/__28498__10_Blade_Alloy_DPS_70mm_EDF_unit_4s_3000kv_1200watt.html

[sihinch]

OK, so I got my set-up in. I'm running a 2900kV motor with a 50A esc and a plastic EDF unit.  I'm getting around 600 watts and 40-something amps WOT, but I have a throttle lag......

When I go to full throttle, it takes some time to get to full revs.  In the lower end of the throttle curve, the response seem instantaneous, but when I'm going from say 2/3 to full, the motor ramps-up noticeably.  You can hear the revs building, even after my throttle stick is at max.

Any ideas, anyone?

[sihinch]

OK, so I calibrated the throttle on the esc and that didn't help. So I bit the bullet and swapped the esc. I put in a 60A plush, which I know are good.

I started to run the moto up, it all sounded good, advanced to full throttle and BLAM! Fan blades exploded.

Now I'm back to waiting for a spare fan unit. 

[flying saucer]

Sorry to hear that. It definitely shouldn't explode at just 600watts unless something was loose or drastically out of balance (motor mount, shaft adapter etc)..as far as the throttle lag, sounds like it was caused by friction, the motor was struggling to put out the rpms.

PS. The changesun setup i mentioned only draws 40amps or so, but puts out 1.3kg of thrust...you can also put one of these together for ~$30 bucks

[Michael]

I'm a fan of the E-Flite/Habu system (60 amp ESC) for 4S.

If you don't mind the vacuum cleaner sound, it's a solid and reliable unit.

Other than my Habu, I have the system in a GWS A4, and I think Robert Pike has it in his Multiplex Twister.

[wollins]

OK, so I calibrated the throttle on the esc and that didn't help. So I bit the bullet and swapped the esc. I put in a 60A plush, which I know are good.

I started to run the moto up, it all sounded good, advanced to full throttle and BLAM! Fan blades exploded.

Now I'm back to waiting for a spare fan unit. 

Sorry to hear Simon ... but curious as to how these things happen. (since I/m new to EDF's) When fans "explode" where do the bits end up ... in the fuse or do they come out the exhaust area?  Experience with props tels me that the blades should go forward? (into the fuse) Just wanted to confirm.

Colin

Colin

[Ededge2002]

Sorry to hear of your troubles Simon.  The waiting game sucks especially when its such a great looking model!  That tiny wing looks FAST!

[sihinch]

Colin - on this model, the fan and thrust exit are sort of mid-fuse, so the pieces of fan stayed in the fuse and dropped out of the thrust exit when I picked the model up. So they kind of come out the back.

Ed - I don't think this one is fast (from what I've read) because it has a really inefficient thrust exit design.  I bought this one for the looks! 

Jeff - I went with a 4-blade changesun fan, with the 2900kV motor. So we'll see if that works.  If it doesn't, I may go HET6904 or Changesun 10  blade.

S

[Michael]

I bought this one for the looks! 

S

That's why my wife married me. 

[sihinch]

That's beautiful Michael. Deep man, deep! 

[Papa]

You lot are beginning to sound like the "Oprah Winfrey Show"

Jack.

[flying saucer]

Is it this one Simon? 

CS 10 blade rotor, EDFHobbies 2950kv motor, 6s, 3000watts 7lbs of thrust

Can't believe people are getting that kind of power out of a 70mm fan.

Just to put it in perspective a larger 80mm unit used in the Habu 32 only puts out 5.5 lbs of thrust..