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Old Oct 19, 2012, 11:46 AM
Montreal, Canada
Canada, QC, Montreal
Joined Mar 2010
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balancing problem

Hi there,
I got 2 x 70mm 10 blades from HK. Both shafts were out of true from inner dia to outer dia.
I ballanced the fan, bought 4 extra shafts from HK but they are all out of wack.
I would say the runnout on the shafts is at least .010''
I tried with a few HET and Mega motors that run super smooth with other fan setups.

Does anyone know where I could get shafts that are very acurate for this fan?

Thanks
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Old Oct 19, 2012, 11:56 AM
EDF rules... :)
AirX's Avatar
Joined Nov 1999
13,563 Posts
Quote:
Originally Posted by alex_blais View Post
Hi there,
I got 2 x 70mm 10 blades from HK. Both shafts were out of true from inner dia to outer dia.
I ballanced the fan, bought 4 extra shafts from HK but they are all out of wack.
I would say the runnout on the shafts is at least .010''
I tried with a few HET and Mega motors that run super smooth with other fan setups.

Does anyone know where I could get shafts that are very acurate for this fan?

Thanks
There are two companies that sell shaft adapters that are true, Tamjets and Extreme RC. Tam offers 4mm and 5mm shafts and Extreme RC offers 3.17mm,4mm, and 5mm shafts adapters.

Check them out.

Eric B.

BTW I am running Tams equipment but i know Mark at Extreme and he puts out good equipment so its up to your needs.
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Last edited by AirX; Oct 19, 2012 at 11:57 AM. Reason: Added BTW
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Old Oct 19, 2012, 12:13 PM
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Greece, Attica, Athens
Joined May 2011
3,269 Posts
Quote:
Originally Posted by alex_blais View Post
Hi there,
I got 2 x 70mm 10 blades from HK. Both shafts were out of true from inner dia to outer dia.
I ballanced the fan, bought 4 extra shafts from HK but they are all out of wack.
I would say the runnout on the shafts is at least .010''
I tried with a few HET and Mega motors that run super smooth with other fan setups.

Does anyone know where I could get shafts that are very acurate for this fan?

Thanks
I use these

http://www.extremerc.com.au/estore/i...th=146_266_319

Install and forget...
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Old Oct 19, 2012, 12:20 PM
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manuel v's Avatar
Mexico, BC, Mexicali
Joined Aug 2004
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Trying to get a better picture of this fan, gather the data that is in this forum and graph data from RPM, Thrust, Watts.
The result is somewhat bizarre that the data is not accurate and some comp RPM was calculated.
This graph can be improved with clearer information on the actual RPM.
But still gives us an idea.


Serie 1, Blue is RPM vs Watts in.
Serie 2, Magenta is RPM vs Thrust in grams.
Manuel V.
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Last edited by manuel v; Oct 19, 2012 at 06:47 PM.
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Old Oct 19, 2012, 04:45 PM
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United States, CA, SF
Joined Mar 2008
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manuel v,

Can you show us how you calculated some of the RPM?


Thanks,

Gryphon
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Old Oct 19, 2012, 07:02 PM
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Mexico, BC, Mexicali
Joined Aug 2004
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Im use this criterion.

Post 372.

http://www.rcgroups.com/forums/showt...v#post18901297

Example

When using Excel, combined with EDF Changesun graph, we can obtain the following information:

If we want to 28.000 RPM,
It requires:
An engine 90 to 150 grams,
With Kv:
A 4slipo = 2.328.
A 5s lipo = 1863.
A 6slipo = 1552.
Consume 850-900 watts,
And we give a thrust of 1400 grams.
All these data are approximate.


If we want to 32.500 RPM,
It requires:
A motor 110 to 180 grams,
With Kv:
A 4slipo = 2.660.
A 5s lipo = 2.129.
A 6slipo = 1.174.
1000-1100 watts consumed,
And we give a thrust of 1700 grams.
All these data are approximate


If we want 40,000 rpm,
It requires:
A motor 160 to 260 grams,
With Kv:
A 4slipo = 3.326.
A 5s lipo = 2.661.
A 6slipo = 2.217.
1550-1650 watts consumed,
And give us a boost of 2000-2200 grams.
All these data are approximate

Just consider that what we seek is 1800-1900 grams and that will push with 8slipo.
For this the Excel and the chart will tell us that we occupy:
As 37.500 rpm,
An engine of 1560 Kv.
With a weight of 140-230 grams.
And consume about 1400 watts.






Now if we have an motor of 3000 Kv and weighs 90 grams.
That would result in EDF Changesun 70mm 10 blades.

This work 4slipo engine in the range of 35 to 36.000 rpm and in the range of 1250 watts.
Therefore it would not be viable.

To 3sLipo work in the range of 27,000 RPM in the range of 700-750 watts.
Therefore it would be the only thing that could work.
Produce as 1400 grams of Thrust.

Manuel V.
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Last edited by manuel v; Oct 20, 2012 at 12:44 AM.
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Old Oct 21, 2012, 04:42 AM
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United States, CA, SF
Joined Mar 2008
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Hi Manuel V.,

I was looking for %KV. You have it in there.

Nice job.


Thank you,

Gryphon
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Old Oct 21, 2012, 06:32 AM
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United States, TX, Grand Prairie
Joined Nov 2005
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Quote:
Originally Posted by alex_blais View Post
Hi there,
I got 2 x 70mm 10 blades from HK. Both shafts were out of true from inner dia to outer dia.
I ballanced the fan, bought 4 extra shafts from HK but they are all out of wack.
I would say the runnout on the shafts is at least .010''
I tried with a few HET and Mega motors that run super smooth with other fan setups.

Does anyone know where I could get shafts that are very acurate for this fan?

Thanks
Try twisting the shaft adapter onto the shaft while pushing down to get the adapter to bottom out on the shaft....works like a charm for me every time...no run out on the shafts even the old ones.
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Old Oct 21, 2012, 06:34 AM
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United States, TX, Grand Prairie
Joined Nov 2005
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Quote:
Originally Posted by manuel v View Post
Trying to get a better picture of this fan, gather the data that is in this forum and graph data from RPM, Thrust, Watts.
The result is somewhat bizarre that the data is not accurate and some comp RPM was calculated.
This graph can be improved with clearer information on the actual RPM.
But still gives us an idea.


Serie 1, Blue is RPM vs Watts in.
Serie 2, Magenta is RPM vs Thrust in grams.
Manuel V.
I look at wemo data and subtract around 3%....I've been on the mark every time...watts\thrust

The wemo data shows volts\amps\thrust\efflux speeds etc....very thorough data
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Old Oct 21, 2012, 09:18 AM
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Long Island, NY
Joined May 2010
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Quote:
Originally Posted by erh7771 View Post
I look at wemo data and subtract around 3%....I've been on the mark every time...watts\thrust

The wemo data shows volts\amps\thrust\efflux speeds etc....very thorough data
Do you have a link for that data?
Thanks
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Old Oct 21, 2012, 10:22 AM
chuck
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Joined May 2009
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+1
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Old Oct 21, 2012, 10:28 AM
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United States, TX, Grand Prairie
Joined Nov 2005
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http://www.rcgroups.com/forums/showthread.php?t=1167099

Interesting....

It was the eflight housing, wemo rotor

Quote:
An altogether different set up I tried is...
E-flite housing, Medusa 2800kv motor, Wemo mini rotor on 6s. I have no idea if the motor will survive the high current.
6S Wemo rotor
25.09v-21.69v, 97.7A, 95.6ozT, 2151W, 59,350rpm 224mph efflux, 2714kv underload. Initial no load testing showed kv closer to 3200.
anyone try the CS rotor in the eflight housing?

Regards
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Last edited by erh7771; Oct 21, 2012 at 10:34 AM.
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Old Oct 21, 2012, 12:16 PM
Formerly "Heli Copter"
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United States, CA, Watsonville
Joined Apr 2009
416 Posts
Quote:
Originally Posted by erh7771 View Post
http://www.rcgroups.com/forums/showthread.php?t=1167099

Interesting....

It was the eflight housing, wemo rotor



anyone try the CS rotor in the eflight housing?

Regards
\

Here is the CS rotor in an E-flite V-15!

StokHabu 3300 Passes (1 min 35 sec)
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Old Oct 21, 2012, 12:19 PM
Formerly "Heli Copter"
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United States, CA, Watsonville
Joined Apr 2009
416 Posts
Quote:
Originally Posted by erh7771 View Post
http://www.rcgroups.com/forums/showthread.php?t=1167099

Interesting....

It was the eflight housing, wemo rotor



anyone try the CS rotor in the eflight housing?

Regards
Here is two CS rotors in two V-15 housings!

Nicks A10 (7 min 48 sec)
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Old Oct 21, 2012, 12:40 PM
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United States, TX, Grand Prairie
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Quote:
Originally Posted by Heli Copter View Post
Here is two CS rotors in two V-15 housings!

http://www.youtube.com/watch?v=a3L7D...e_gdata_player
lol...did that a 10 go vertical after 20 feet?

nice...

any watts\thrust numbers on the set up?

was it the 3300kv eflite motor?

regards
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