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Jul 04, 2012, 02:26 PM
Registered User
Quote:
Originally Posted by NitroCharged
Is a 2W20 on 4S too much for this thing?
Yes, 4S is too much for this fan with 2w-20.
3S draws around 55 amps depends on the packs.
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Jul 04, 2012, 02:37 PM
Registered User
Tamjets's Avatar
Quote:
Originally Posted by Knife Liddle
Looks like the 4 stator was a little lighter load, but the 7 stator was a little quieter and had a little more power. It will be intresting to see how the graphs compare.
I just take a look between 2 video.

The 7 stators shroud @ 1600 watts put out the same power as 4 stators shroud at 1700 watts.
That show there is effecient gain.

The data effecient gain is very close to my TJ100 5 stators VS. TJ100HP 7 stators.
Jul 04, 2012, 05:00 PM
Team30 Micro EDF
NitroCharged's Avatar
3rd-dem - thanks for the input.
Jul 04, 2012, 05:17 PM
Diverted by planks
tracknoob's Avatar
After the sales pitch, Mark said: (snips)

Quote:
The instructions I was talking about earlier…are now done, cover the assembly and balancing methods needed with the fan

I have sold maybe one bare fan unit for every 20 assembled units, so it has not been a priority.

Alloy housings have no give, they do not absorb vibration and they will show any small imbalance that might be quite acceptable with a plastic housing.

the rotors are not perfect moldings, I often run a file on the edge of the spinner seat so as to loosen up the fit and allow the spinner to be rotated with a little force.

yes the spinners often need balancing, if you are running a 2W30 on 6s its getting close to the rotors limits in RPM and it will vibrate badly unless balanced.

bolt issue has been addressed, the Taiwanese adapters that are modified and machined were not tapped out deep enough

… unfortunately yours were not done having been sent out last week before I discovered it.

Its a mute[sic] point now anyway as I have been discarding 50% of them in every batch…

the "grip" hole(s)… are not put into the Taiwanese adapters because you are supposed to use pliers to grip the smooth machined end of the adapter, its done this way on purpose, the hole can be misleading and cause people to overtighten…

if it were my choice it would not be there in the custom adapters, unfortunately they come pre drilled so I cannot eliminate it.

…the thicker the motor shaft the easier it is to balance up any fan,… 3.17mm shafts are the hardest to balance out when used with alloy housings.

You know Jim, this makes me think better not to sell bare fan units… Alloy housings are not easy to work with, they forgive nothing, and its not worth having the inexperienced run into problems with them for the sake of a sale.

It requires more than just a balanced rotor when assembling these as I have just outlined.

The spinners you got were the old style that fitted to machined down rotors, and they all require balancing, its not hard

Fit the same parts into a flexible plastic housing and likely you will get it good enough not to need that final tuning.

I build fans every day, its easy for me, its all subconcious tasks, makes it hard to explain to others how to do it.

Stick it all into a composite housing, plastic etc, and less precision is needed. Go from 3.17mm shaft to 4mm or even 5mm, and much less fine tuning is needed

I can assemble an HET motor with 4mm shaft and it takes far less time to finish the fan compared to the 3.17mm.

I can put the same balanced rotor onto a 4mm shaft and not need to rotate it at all to harmonically align all the parts, that cannot be said for a 3.17mm shaft.

I never said I balance with 0.2 grams of tape, I said you COULD end up with 0.2 grams of tape inside your spinner and that it is not a lot of weight.

Working with 5mm shafts is easy, dead easy compared to 3.17mm shafts.
Jul 04, 2012, 06:32 PM
Registered User
Quote:
Originally Posted by Tamjets
I just take a look between 2 video.

The 7 stators shroud @ 1600 watts put out the same power as 4 stators shroud at 1700 watts.
That show there is effecient gain.

The data effecient gain is very close to my TJ100 5 stators VS. TJ100HP 7 stators.
Tan, I know this is off topic, but have you given any thought to a precision 5mm shaft adapter for the Change Sun 12 blade 90mm like you have for the 70mm?
Jul 06, 2012, 04:06 PM
Plane crazy
Tartago's Avatar
Quote:
Originally Posted by anlucas
Tartago, I run 4000mah packs as a minimum with the 3300kv. It pulls 80-90amps. I get max 4 mins.
Lucas, What about the sound? On mine the motor was much louder to appreciate the EDF's.
Jul 06, 2012, 04:49 PM
Registered User
anlucas's Avatar
Quote:
Originally Posted by Tartago
Lucas, What about the sound? On mine the motor was much louder to appreciate the EDF's.
Tartago,

maybe you need to balance the fan some more.

This is how mine sounds. A bit noiser than the Turnigy L2855 motors but still pretty good.

HK Mig-15 70mm CS 10 Blade CS480-3300KV (1 min 47 sec)
Jul 06, 2012, 04:53 PM
Hawk Fanatic
SkylineFlyer's Avatar
Quote:
Originally Posted by anlucas
Tartago,

maybe you need to balance the fan some more.

This is how mine sounds. A bit noiser than the Turnigy L2855 motors but still pretty good.

http://www.youtube.com/watch?v=uMLDrwQoMlg
That sounds amazing. Mine is quiet. I don't hear anything.
Jul 06, 2012, 04:55 PM
Registered User
anlucas's Avatar
Quote:
Originally Posted by SkylineFlyer
That sounds amazing. Mine is quiet. I don't hear anything.
Which motor and airframe?

Composite airframes are mute with this fan and a silent motor.
Jul 06, 2012, 04:59 PM
Plane crazy
Tartago's Avatar
Quote:
Originally Posted by anlucas
Tartago,

maybe you need to balance the fan some more.

This is how mine sounds. A bit noiser than the Turnigy L2855 motors but still pretty good.

http://www.youtube.com/watch?v=uMLDrwQoMlg
The EDF balance is ok. Is the motor sound that is not the same than yours, even being the same Cyclone power 3300kv. Mistery.
Jul 06, 2012, 05:01 PM
Hawk Fanatic
SkylineFlyer's Avatar
Quote:
Originally Posted by anlucas
Which motor and airframe?

Composite airframes are mute with this fan and a silent motor.
Using the venom epo F-86 with stock motor.
Jul 07, 2012, 06:05 AM
Long-Time Member
James Frolik's Avatar
Quote:
Originally Posted by flylow2011
Quote:
Originally Posted by NitroCharged
Is a 2W20 on 4S too much for this thing?
Yes, 4S is too much for this fan with 2w-20.
3S draws around 55 amps depends on the packs.
I tested the CS70 fan with a HET 2W-20, 3s Zippy 2800, and Cyclone Power ESC-60A-SBEC controller on a vertical thrust stand. The stand's digital scale has zero-centering (to offset the stand's weight) and measures up to 3 kilograms in 1-gram increments.

I could only run the CS70 for about 15 seconds because the amps were too high — and the battery was not even fully charged. A full LiPo would be bad; this is not a good setup for the 2W-20 motor.

CS70
Note: This was not a freshly charged battery.
Load Voltage: 10.36 after 15 sec.
Watts: 774
Amps: 74
Thrust: 1148 grams

Watts and thrust on my test stand are nice, but the amperage is not.

Compare that to my 2W-20 test results (below) using a WeMoTec MiniFan with the same 3s Zippy 2800 LiPo, but now it's freshly charged. Here the input is over 1 volt more than with the CS70 (and a used battery). Thrust is only 20% less but the amps drop by nearly 50%. Interestingly, the watts drop by 46% without sacrificing too much thrust loss.

WeMoTec MiniFan
Note: Freshly charged battery.
Load Voltage: 11.78 after 30 sec.
Watts: 418
Amps: 37.9
Thrust: 917 grams
Jul 07, 2012, 09:33 AM
Registered User
That CS10 wattage at 774W is a bit off, compared to what you should be able to get.
I get 1.25Kg for 700W with 4S on a 2600KV.
4S on a 2800KV is 800W for 1.35Kg
1.1Kg thrust should only need 600W area or so.

3350KV should give about 1.1Kg on 3S, so that part seems fine enough. But I don't know why it is drawing that excessive current. It should be more like 63A area. I think if current is abnormally high it shows the motor is over-stressed a fair amount.

For the Wemo, 900g Vs 1150g is not 'the same' really. It is actually a fair way apart and the current needs rise faster than thrust output. So for 1150g in the Wemo - to match the CS10 - that Amps number would be more towards 45A area I would think. Still a lot more efficient than the CS10 combo gave.

I am guessing the 2W20 is not up to the task for the CS10, thus over-loaded, inefficient and eating Amps madly. It is only a 40mm motor too - but it is 60A rated so even 800w shouldn't be too much for it to at least live through fine. It does still seem a bit excessive wastage... but maybe it is totally normal to be happening. And maybe 3S voltage, pushing for those higher power limits, at very high current, just doesn't work well in that motor.
I am not sure... but it is not good.
Jul 07, 2012, 01:34 PM
Long-Time Member
James Frolik's Avatar
Quote:
Originally Posted by PeterVRC
That CS10 wattage at 774W is a bit off, compared to what you should be able to get... I am guessing the 2W20 is not up to the task for the CS10, thus over-loaded, inefficient and eating Amps madly.
Yes, I can accept that "watttage at 774W is a bit off."

I should note that on my test stand I use a HobbyKing POWatt Meter for my electrical measurements. It's not the most accurate gauge but gives a useful ballpark figure.
Jul 07, 2012, 05:40 PM
The best in EDF since 2005
Extreme_RC's Avatar
The CS rotor is a high load, doesnt matter what the motor is "rated" for, fact is this rotor needs a V8 with torque behind it, not a 1.4L TSI engine from volkswagen Think long can inrunners with a decent amount of mass.
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