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Old Nov 25, 2012, 04:36 PM
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ViperVJG73's Avatar
Germany, SH, Neumünster
Joined Dec 2011
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Hi guys, sorry for my stupid question.
Use you all these newer heavier 51 grams fans for your tests? Tell us please the weight of the fans you are testing.
It is very of concern.

Thanks.
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Old Nov 26, 2012, 01:34 AM
scunna
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United Kingdom, England, South Shields
Joined May 2007
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Quote:
Originally Posted by dlxpkg2000 View Post
I'm going "batty" with these figures....I want to run the C.S 12 blade/90mm,Emax 1650kv on a C.C. 100 Lite,(w/heatsink) on 8s. 2x4s 4000mah,30c in series, in a 7 lb. H.T.G L-39. I've heard this fan would have too much amp draw for this set-up...Anyone want to chime in? Thanx in advance
changesun 12 blade fan 90mm 700-68 1400kv 8s 4400 65-130c nanotech lipos (3 min 25 sec)
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Old Nov 26, 2012, 10:28 AM
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MagnusEl's Avatar
Sweden, Gävleborg County
Joined Jan 2004
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Quote:
Originally Posted by manuel v View Post
But with a Kv of 1709, everything is very different.
Yeah...Little too high Kv for 6 cells on the 90mm 12 blade I think.
I can confirm that the Kv rating from HobbyKing is wrong, I get Kv 1730 @ 11,35 volts...that is measured with a Kv meter. have not run it yet...
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Old Nov 26, 2012, 12:48 PM
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Mexico, BC, Mexicali
Joined Aug 2004
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Quote:
Originally Posted by MagnusEl View Post
Yeah...Little too high Kv for 6 cells on the 90mm 12 blade I think.
I can confirm that the Kv rating from HobbyKing is wrong, I get Kv 1730 @ 11,35 volts...that is measured with a Kv meter. have not run it yet...
Very consistency with my simple Kv read.
Motor 1.
Io=1.35A. No Load.
With little blade.
1.64A, 11.75V, 20,000 rpm, 1702 Kv.

Motor 2 with little blade.
1.8A, 12.05V, 20,600rpm, 1709 Kv.

For those motor real Kv is A little more high.
same your motor. 1730.


Manuel V.
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Last edited by manuel v; Nov 26, 2012 at 05:46 PM.
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Old Nov 26, 2012, 04:50 PM
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Chi-Town, Il. U.S.A.
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Scunna, What size ESC are you using in that set-up.?........
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Old Nov 26, 2012, 05:38 PM
scunna
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United Kingdom, England, South Shields
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Originally Posted by dlxpkg2000 View Post
Scunna, What size ESC are you using in that set-up.?........
120 amp turnigy hv from hk
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Old Nov 26, 2012, 05:56 PM
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Mexico, BC, Mexicali
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Quote:
Originally Posted by dlxpkg2000 View Post
I'm going "batty" with these figures....I want to run the C.S 12 blade/90mm,Emax 1650kv on a C.C. 100 Lite,(w/heatsink) on 8s. 2x4s 4000mah,30c in series, in a 7 lb. H.T.G L-39. I've heard this fan would have too much amp draw for this set-up...Anyone want to chime in? Thanx in advance
very mush for motor.
Around 38,000 rpm, 3400 watts , 117A.

And only if the motor and batteries support it.
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Old Nov 26, 2012, 06:01 PM
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United States, NM, Clovis
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I received my fan assembly from xflight and wanted to confirm that it weighed in at 52g.
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Old Nov 26, 2012, 09:50 PM
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Canada, ON, Burlington
Joined Jan 2009
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I was having a tough time dynamic balancing one of my fans over the last few days. It would come very close at less than 3/4 throttle but above that it would vibrate as though it was out quite a bit. Figured something was changing position. I glued the adapter to fit tight on the motor shaft and that helped considerably but I couldn't get it perfectly smooth. I also used some locktite on the motor shaft just where it contacts the inner race of each bearing as the shaft had some slight play in each bearing. This helped a little but the final tiny bit of vibration couldn't be fixed until I reduced the play between the adapter and fan hub. There was a little slop as the fan sat on the adapter so a thin layer of CA was added on the inner hub where it contacts the adapter. Naturally it was too tight at first but I reamed it to fit with another spare adapter. With this last bit of slop removed the fan is now balancing much easier and more consistent at every power setting.
The point is, all play must be reduced as much as possible if you want to dynamic balance the fan properly.
Cheers
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Old Nov 27, 2012, 02:48 AM
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Germany, SH, Neumünster
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Quote:
Originally Posted by DamonH View Post
I received my fan assembly from xflight and wanted to confirm that it weighed in at 52g.
THX for your info!
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Old Nov 27, 2012, 07:52 AM
Too many numbers
United States, OH, Troy
Joined Oct 2010
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Hi guys. I have a new airframe coming, and I've had this fan in a drawer for about six months with no motor. Originally I planned on 1200KV at 10S in another airplane, which put it around 45000 rpm, but then I got cold feet. I decided that since there were some issues with blades departing the hub, I'd use a different fan. Now for my new airframe, I want to keep my RPMs down to a reasonable level with this fan. I'm putting a 1500KV motor on it and plan to use 6S. So at this speed (around 33k rpm), will I need to epoxy the blades? If so, how exactly do you do it? Hysol, or epoxy? Thanks!
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Old Nov 27, 2012, 08:03 AM
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Canada, ON, Burlington
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Quote:
Originally Posted by c131frdave View Post
Hi guys. I have a new airframe coming, and I've had this fan in a drawer for about six months with no motor. Originally I planned on 1200KV at 10S in another airplane, which put it around 45000 rpm, but then I got cold feet. I decided that since there were some issues with blades departing the hub, I'd use a different fan. Now for my new airframe, I want to keep my RPMs down to a reasonable level with this fan. I'm putting a 1500KV motor on it and plan to use 6S. So at this speed (around 33k rpm), will I need to epoxy the blades? If so, how exactly do you do it? Hysol, or epoxy? Thanks!
have you read through this thread recently? How much does your fan weigh (without adapter or spinner)?
If it is one of the weaker plastic fans, gluing will not prevent failure of this fan. Failure will cause more damage than just the shroud, you can expect a bent motor shaft as well, and whatever damage to the model that results from an uncontained failure without warning.
Replacement fans are available and the cost of buying a stronger fan is cheap insurance.
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Old Nov 27, 2012, 08:10 AM
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United States, NM, Clovis
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Quote:
Originally Posted by 4stripes View Post
have you read through this thread recently? How much does your fan weigh (without adapter or spinner)?
If it is one of the weaker plastic fans, gluing will not prevent failure of this fan. Failure will cause more damage than just the shroud, you can expect a bent motor shaft as well, and whatever damage to the model that results from an uncontained failure without warning.
Replacement fans are available and the cost of buying a stronger fan is cheap insurance.
I can attest to the weaker (lighter) fan coming apart and destroying fan/shroud and motor. Luckily it hapened on my test sled before it was installed in a plane. If you have the 45g fan and not the 51ish g fan I would consider ordering the new fan. I just received my new unit from xflight and it is 52g.
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Old Nov 27, 2012, 08:23 AM
Too many numbers
United States, OH, Troy
Joined Oct 2010
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Are you weighing the entire fan unit (with the spinner), or just the blades? I'll look through the thread. I bought mine in June which was right when folks started talking about the problem. Is it 52 grams per blade? I actually have the program I used when I worked at General Electric for balancing compressor blades (uses weight of each blade and tells you where to put them) somewhere. Maybe I'll try and dig it up. lol Brings back memories- not all good...
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Old Nov 27, 2012, 09:21 AM
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United States, NM, Clovis
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Quote:
Originally Posted by c131frdave View Post
Are you weighing the entire fan unit (with the spinner), or just the blades? I'll look through the thread. I bought mine in June which was right when folks started talking about the problem. Is it 52 grams per blade? I actually have the program I used when I worked at General Electric for balancing compressor blades (uses weight of each blade and tells you where to put them) somewhere. Maybe I'll try and dig it up. lol Brings back memories- not all good...
It is 51-52g for the whole fan and the aluminum washer on the front and back. You do not weigh the motor adapter with it. That GE program sounds interesting.
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