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Old Jan 22, 2013, 03:17 AM
efx
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Thank you that's very helpful. The 8x4 is the rated one for this motor and the 7x4 is the other. I do have a wattmetter so I finally can use that.

QUOTE=theothercliff;23889728]Motor, ESC, battery, and prop are a 4 way balancing act.

Assuming first of all an ESC and battery that can handle more power, a bigger prop makes the motor draw more power. The wires in the motor are only rated for a certain amount of power and will burn out if you put too big a prop on it.

For a given motor size (power capacity) say 200 watts, a high KV motor rating translates into a small prop turning a high RPM that consumed 200 watts. A low KV translates into a large prop spinning slowly and also consuming 200 watts. You cannot just put a large prop on a high KV motor and hope that it turns slowly enough to not burn out.

With electrics, you can always safely use a smaller prop. The only down side is less power. You can safely run an electric motor without any prop. It is the bigger props that will make something burn out.

If you have a prop that works well on your motor and does not overheat, start from there. Measure the amp draw at full throttle with that prop and compare it to the motor spec. If you want and need and can have more amps without burning a motor out, you can increase the prop size a little. Even if you can't increase the prop size, you can get more thrust by increasing the diameter and decreasing the pitch at the same time. For more speed and less thrust you decrease diameter and increase pitch. Figure 1 inch of diameter equals about 2 of pitch so you could go from say a 9x6 to a 10x4.

On the internet there are online brushless motor calculators that can help you. Find one that has some defaults for the things you don't understand and experiment. Get an amp meter / watt meter and some reasonable props and experiment. Be careful to never over amp any of the components.

With an amp meter you can increase throttle till you see you are close to max amps. If you get to max amps before max throttle, cut a little diameter off, rebalance, and try again.

One test I use when close is to run it at full power for 10 whole seconds. Let the heat soak out for 10 seconds of power off. If it is too hot to hold firmly, the prop is too big and you shouldn't have done that in the first place. Start with small props and work your way up in small increments this way. Make sure you don't over amp your ESC or battery either and that really requires an amp meter or learned knowledge like the fact that I know that a 6x4 prop on a 3 cell 2000KV will pull about 20 amps.[/QUOTE]
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Old Jan 22, 2013, 08:28 AM
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That's pretty smooth video, how do you mount your camera or are you using the keychain type? I know those don't bounce much. I'm getting the shakes a bit on mine so I got some tuning to do.
It's a GoPro, I have it mounted to a 3mm plywood plate suspended under the frame, with the battery strapped to the underside of the plate. The weight of the battery helps absorb some of the vibrations. It's not perfect yet, but it is progressing.

Also, I had a 450 kit and I ran 9x4.7 props on it. It was a good combo with 3s battery and 930kv motors.
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Old Jan 22, 2013, 09:21 AM
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Well I got another question as I'm not familiar with props much if any until this build. I currently have 8x4 props on the 450 kit. What would be the resutl of say going to 7x4 I guess or 9x4.5 size. I was thinking of going up one size hoping it will help keep the humming down a bit.
Ditto efx's comments. Larger props running at lower rpm are quieter but it is a balancing game. If the props are too small the motors will not be able to generate their full power. If they are too large the motor and ESC might overheat. even to the point of catching fire.

Anyone experimenting with different prop/motor calculations should definitely own a watt meter as efx posted. You can buy a good one from Hobby King for around $25.

http://www.hobbyking.com/hobbyking/s..._Analyzer.html
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Old Jan 22, 2013, 11:02 AM
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New video here, taken yesterday so you can see how much snow we have had in the UK. Horrible jello effect on the 808 as it was mounted under the rear prop.

Tricopter HD Winter Wonderland with GoPro and 808 #16 camera (3 min 58 sec)
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Old Jan 22, 2013, 12:27 PM
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Hi Guys sorry for being lazy and not completely checking this monster thread but its been a long time that I checked on the kk2 thread so I want someone to guide me to the post which explains how to set up CPPM mode using the KK2...
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Old Jan 22, 2013, 01:32 PM
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Hi Guys sorry for being lazy and not completely checking this monster thread but its been a long time that I checked on the kk2 thread so I want someone to guide me to the post which explains how to set up CPPM mode using the KK2...
Just activate it on the KK and connect a single female to female servo lead into a receiver capable of combining the PPM signals.

I use the Frsky V8R7-SP...

http://www.frsky-rc.com/ShowProducts.asp?id=48

...and that is pretty much it.
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Old Jan 22, 2013, 01:37 PM
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Originally Posted by Akcopter View Post
Hi Guys sorry for being lazy and not completely checking this monster thread but its been a long time that I checked on the kk2 thread so I want someone to guide me to the post which explains how to set up CPPM mode using the KK2...
1.2 (I think) release notes, linked from Page one. A.
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Old Jan 22, 2013, 01:43 PM
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Hi Guys sorry for being lazy and not completely checking this monster thread but its been a long time that I checked on the kk2 thread so I want someone to guide me to the post which explains how to set up CPPM mode using the KK2...
Be careful which version ( double check the FAQ ) as the labels were wrong in at least one FW.
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Old Jan 22, 2013, 02:18 PM
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Originally Posted by Truglodite View Post
Another thing I'd like to see added to the firmware is gimbal tilt. Same as the current gimbal, but with an option to use AUX for controlling the tilt angle in flight.
You'll be wanting this then

http://www.rcgroups.com/forums/showt...1#post23894151
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Old Jan 22, 2013, 02:20 PM
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Originally Posted by Akcopter View Post
Hi Guys sorry for being lazy and not completely checking this monster thread but its been a long time that I checked on the kk2 thread so I want someone to guide me to the post which explains how to set up CPPM mode using the KK2...
The one lead plugs into the KK2 first (top) input channel.
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Old Jan 22, 2013, 03:30 PM
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Be careful which version ( double check the FAQ ) as the labels were wrong in at least one FW.
Yes, V1.2 has Yaw and Throttle transposed in the CPPM Setting Menu. This was fixed in V1.3
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Old Jan 22, 2013, 05:48 PM
efx
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Okay I just made myself a parallel battery adapter. Would just the one battery voltage plug work or would I need one for each? I know this seems basic, but since I have never actually flow with a set of batteries I don't know what others have experienced with something similar. I'm guessing just the one balance lead I have will be fine if I'm using the same size batteries unless I can get voltage on each individual battery from the controller, but my guess is this is not necessary. I still haven't tested this on the quad but adapter is all done and I just tested it individually on the one battery and all seems good to go. In any case, I just want to make sure I don't make any fires.

Darn, it looks like one of my wattmeter plugs is soldered wrong...ahhh
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Old Jan 22, 2013, 06:04 PM
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...cool

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Originally Posted by Senator315 View Post
For my new toy I wanted to build something different to the regular quads, tri's etc.

I used an X525V3 as the starting platform. From the kit I used the center plates, motor mounts and landing gear.
The new booms are 16mm round aluminium tube.
SIze:
Front to rear 500mm
Left to right 545mm
The battery mounts at the rear to get the right COG. The mount is 3mm x 40mm x 105mm, perfect size for a 3S 2200mAh LiPo which is attached with Velcro.

Other parts
FC2812 motors
HK F20A SimonK ESC's
KK2 1.5

It's also a cross between a quad and a tri. Flying in a Quad + config with a tail servo. All the yaw is controlled by the tail. To do this, you go into mixer editor and set the rudder on ch1, ch2, ch3 and ch4 to zero, then setup ch5 as servo. Set the rudder on ch5 to how much movement you need and the offset to level the tail.

Here's a vid of it, mind you it's very windy. On a nice day it flies as good as any quad of this size while looking so much cooler.
More pics at the end of the clip.

I call it The Jet Fighter
Enjoy and happy new year to everyone here at RCG, family and friends.

http://youtu.be/OYSZ5MqcGsY
That's a very cool and interesting project...it did handle that crazy wind very well.Thanks for sharing bro
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Old Jan 22, 2013, 06:08 PM
efx
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Here's what I had done. I can plug a battery from either side which works, but now I need a nother adapter to plug it to the quad side, the connectors don't match if I want to plug the wattmeter between them...that manual has two in and two out which these plugs don't have. They are one in and one out...I just used the batteries to make sure I could plug them in on either side. I guess this is what happens when there's no standard. I guess I can always redo the load side. I just found another battery plug I had cut that I can use to reverse this side. I'll just soldered the correct side on the other end...I'll have to reverse the load end. The one I found is too big 12awg which is more of a pain to solder.
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Old Jan 22, 2013, 07:37 PM
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Originally Posted by efx View Post
Here's what I had done. I can plug a battery from either side which works, but now I need a nother adapter to plug it to the quad side, the connectors don't match if I want to plug the wattmeter between them...that manual has two in and two out which these plugs don't have. They are one in and one out...I just used the batteries to make sure I could plug them in on either side. I guess this is what happens when there's no standard. I guess I can always redo the load side. I just found another battery plug I had cut that I can use to reverse this side. I'll just soldered the correct side on the other end...I'll have to reverse the load end. The one I found is too big 12awg which is more of a pain to solder.
From my experience there is a standard, a very strong one that all manufacturers adhere to:

"Whatever connector I am currently using will not be available on the product I am ordering. To do this effectively, every three months introduce a new one that has no clear advantage over the ones they have supplied in the past, just something new I have to buy or cut off and replace."

That has been my experience...
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