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Old Sep 26, 2012, 09:30 PM
Banzai Institute
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United States, NY, West Seneca
Joined Oct 2005
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Yea I hear ya Herb. It looks like a 7oz penalty for the Lander housing. Like I said I am not settled on the fan yet. I do want to keep the 8s option though. It seems the plane needs nose weight to balance out and I always look for volts over Amps. Thanks for your thoughts.

Manyman what fan are you using? Is that the $17 outrunner eating 3000W? maybe it wasn't up to it.
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Old Sep 26, 2012, 09:34 PM
edf flyer
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United States, CA, Marina
Joined Feb 2009
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Originally Posted by Herb View Post
Hi, sounds like you completely demagnetized that poor 180g $17 motor What are you thinking of as a fan replacement? that fan is an inefficient amp hog.
I'm thinking about putting my het fan and motor. 700-68-1400kv.
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Old Sep 26, 2012, 09:36 PM
edf flyer
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United States, CA, Marina
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Originally Posted by buckaroo View Post
Yea I hear ya Herb. It looks like a 7oz penalty for the Lander housing. Like I said I am not settled on the fan yet. I do want to keep the 8s option though. It seems the plane needs nose weight to balance out and I always look for volts over Amps. Thanks for your thoughts.

Manyman what fan are you using? Is that the $17 outrunner eating 3000W? maybe it wasn't up to it.
Cs12b. And I added 4oz of weight in the nose
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Old Sep 26, 2012, 09:38 PM
edf flyer
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United States, CA, Marina
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Originally Posted by Herb View Post
Hi, sounds like you completely demagnetized that poor 180g $17 motor What are you thinking of as a fan replacement? that fan is an inefficient amp hog.
How can u tell if a motor is demagnetized
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Old Sep 26, 2012, 09:50 PM
Banzai Institute
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United States, NY, West Seneca
Joined Oct 2005
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Mannyman535, Glad to hear you got her down safe. I have 2 of the CS12b bought for testing in a Citation but am afraid to use them. +1 on the HET motors. I had planned to use one with an 8mm shaft for the CS12b but they seem to frequently blow up even under 2800W which was my target for the Citation

Ravi I am liking your 10s setup. Sounds like a good option. Looks like I should look into the ole trusted Wemo.

Cheers guy's
Dean
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Old Sep 27, 2012, 04:54 AM
RAVI KOTHARI
Joined Nov 2005
259 Posts
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Originally Posted by buckaroo View Post
Mannyman535, Glad to hear you got her down safe. I have 2 of the CS12b bought for testing in a Citation but am afraid to use them. +1 on the HET motors. I had planned to use one with an 8mm shaft for the CS12b but they seem to frequently blow up even under 2800W which was my target for the Citation

Ravi I am liking your 10s setup. Sounds like a good option. Looks like I should look into the ole trusted Wemo.

Cheers guy's
Dean
The wemo is a great fan. and the het 650 is a beast.
higher cell count will be slightly more efficient.
just ordered a new midi from efflux rc. shipped in 12 hours.
will post on combination, hope all goes well.
although 600 gms in the nose may not be enough weight.
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Old Sep 27, 2012, 11:49 AM
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Originally Posted by Mannyman535 View Post
How can u tell if a motor is demagnetized
When it starts pulling a lot more amps than expected it's a sign that the magnets are done.

Also, usually the esc is the first to go right after the motor demagnetizes.

A very rough rule of thumbs is about 8 Watts per motor gram.

So for reliable operation at 3000W you need a 350g motor or so (although some motors are better than others ). Esp. in the summer ... Dont' expect a 180g $17 motor to last more than one flight at 3000W ...

There are many quality motors out there, Neu, Het, Leopard, HKY, some Turnigy SK3 edf inrunners, the JePe chinese edf inrunners, and a few more open endbells chinese inrunners like Tenshock, and a few others. Plus of course high end stuff like Plettenberg and Schuebeler.

To make a long story short, if you are aiming at 3000W or so, your motor should be > 300g at least.
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Old Sep 27, 2012, 11:56 AM
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Originally Posted by ravikoth View Post
The wemo is a great fan. and the het 650 is a beast.
... although 600 gms in the nose may not be enough weight.
On my L-39 I have zero grams of lead in the nose.

If you plan your layout correctly, and use the CG I posted five months ago on the first page of this thread, you will be fine
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Old Sep 28, 2012, 06:40 AM
edf flyer
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United States, CA, Marina
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Originally Posted by Herb View Post
When it starts pulling a lot more amps than expected it's a sign that the magnets are done.

Also, usually the esc is the first to go right after the motor demagnetizes.

A very rough rule of thumbs is about 8 Watts per motor gram.

So for reliable operation at 3000W you need a 350g motor or so (although some motors are better than others ). Esp. in the summer ... Dont' expect a 180g $17 motor to last more than one flight at 3000W ...

There are many quality motors out there, Neu, Het, Leopard, HKY, some Turnigy SK3 edf inrunners, the JePe chinese edf inrunners, and a few more open endbells chinese inrunners like Tenshock, and a few others. Plus of course high end stuff like Plettenberg and Schuebeler.

To make a long story short, if you are aiming at 3000W or so, your motor should be > 300g at least.
Thanks
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Old Sep 28, 2012, 07:53 AM
RAVI KOTHARI
Joined Nov 2005
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Originally Posted by Herb View Post
On my L-39 I have zero grams of lead in the nose.

If you plan your layout correctly, and use the CG I posted five months ago on the first page of this thread, you will be fine

could you recommend a placement for this model? using a wemotec Midi ,

what battery weight & esc location.
Also to keep weight low in the tail i plan to use the HXT 900's on the 2 elevator Halves. do you think those servos are ok for this application.

Thanks.
Ravi
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Old Sep 28, 2012, 10:41 AM
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Australia, SA, Ingle Farm
Joined Feb 2010
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Originally Posted by ravikoth View Post
could you recommend a placement for this model? using a wemotec Midi ,

what battery weight & esc location.
Also to keep weight low in the tail i plan to use the HXT 900's on the 2 elevator Halves. do you think those servos are ok for this application.

Thanks.
Ravi
I wouldn't use anything other then digital metal gear servos, I have used turnigy 929mg servos in my het f20 without problems. But it's a 70mm edf airframe.

I've just ordered one of the l59's from hk.. they look remarkable ! My dad has.a viperjet and I really liked the look of that, despite the broken tail in shipping.

I would like to know more about power setups... 6,8 or 10s the way to go. I'm leaning towards 8s, no real reason however. Something around a 3300mah to 4000mah packs? I'm sure flight.time would be no more then 4 mins

Thanks
Adam
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Last edited by AdMan; Sep 28, 2012 at 10:52 AM.
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Old Sep 28, 2012, 11:23 AM
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with 4400mah and 100+ amps I'm getting less than 4 mins.. depends on how you build it though
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Old Sep 28, 2012, 11:39 AM
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Irvine, Calif USA
Joined Feb 1999
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Originally Posted by ravikoth View Post
could you recommend a placement for this model? using a wemotec Midi ,

what battery weight & esc location.
Also to keep weight low in the tail i plan to use the HXT 900's on the 2 elevator Halves. do you think those servos are ok for this application.

Thanks.
Ravi
Hi Ravi, I believe many of your questions are answered earlier in this thread ?

Good quality twin 9g plastic gear servos are fine for the elevators, as long as they fit and have zero slop and good centering.

You can see detailed pictures of my elevator installation at the beginning of this thread.
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Old Sep 28, 2012, 08:34 PM
RAVI KOTHARI
Joined Nov 2005
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Originally Posted by Herb View Post
Hi Ravi, I believe many of your questions are answered earlier in this thread ?

Good quality twin 9g plastic gear servos are fine for the elevators, as long as they fit and have zero slop and good centering.

You can see detailed pictures of my elevator installation at the beginning of this thread.

thanks herb.
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Old Oct 02, 2012, 11:43 AM
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