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Old Feb 19, 2012, 12:04 AM
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Hey guys!

Thanks and well i haven't get to weight it yet since the ESC and the batts havent arrive. the plane does look crappy and slightly heavier then the stock ones, actually i was just planning to fly it stock first before i go further and get use to flying it first but as you can see in one of the pic, the fan blade actually broke before take off, think it kinda vacuum in a small piece of stone or sand and broke the blades, damn! So i had to start ripping it apart.

So i am just wrapping this to make sure its really robust since this is gona be a training kit, i had already flew the f18 and get the hang of it, that plane is soo easy to fly tho, and it hand launches easily.

As for the blackbird, how do you guys accurately get the CG and how do you know wether the nose or the tail is heavy? Please do help me out here guys, as all i do now is have a tip of my finger on the CG spot and see which part drops below.

Thanks guys

P/S : Aros, how is lucky number 7?
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Old Feb 19, 2012, 12:12 AM
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Oh yeah guys one more question tho, how do you guys join the ESC throttle connection to the Rx? Since there is two, do you guys use a 'Y' connection for it? And i also heard before from some1 saying that you have to mod on one of the ESC, because previously i always had the problem of either one motor would stop while throttling or WOT.

Thanks guys!
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Old Feb 19, 2012, 12:29 AM
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Joined Apr 2003
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Y connection works - be sure to set your throttle range on the ESCs - this usually is done by having the TX throttle at 100% - connecting power - waiting for two beeps, then going to zero on the throttle.
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Old Feb 19, 2012, 12:43 AM
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Hi mate,

you mean just for the first time connection? or every single time when the battery is connected to the ESC? Anyways mine is OPTO so i would be using an external receiver pack. Another question is how do you program the ESC? and what is Dynamic braking? is it reverse thrust? below is the ESC that i bought.

http://www.hobbyking.com/hobbyking/s...idProduct=7341

Thanks guys!
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Old Feb 19, 2012, 12:49 AM
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Originally Posted by Kenzo77 View Post
P/S : Aros, how is lucky number 7?
Waiting on her all new Wicked power plant thanks for asking!
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Old Feb 19, 2012, 12:55 AM
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sounds good! just wish we were all neighbours in the same area lol, it would be awesome to hang out and fly those birds together.

Anyways does all the ESC comes with programming card? if not where can i get them? below is my ESC that i ordered, hopefully reaches here on monday.

http://www.hobbyking.com/hobbyking/s...idProduct=7341

Thanks guys!
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Old Feb 19, 2012, 01:45 AM
I always find software bugs!
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Joined Nov 2010
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Kenzo77,

Dynamic braking is used on R/C electric cars (and real life trains and electric cars). When the car is coasting the motor becomes a generator. This current (at least with the method I am familiar with) is sent to a variable resistance to create a load on the motor and as a result, causes a braking effect on the vehicle. I assume that R/C ESCs use this current to electronically apply force in a reverse direction, but the result it the same.

Long story short, you won't use it on your SR-71! Just turn it off.

Your ESC will not come with a programming card. You will need to buy one separately.

I hope you noticed that the ESC you purchased does not have a BEC, and you will need to provide your own way of powering your receiver and servos from the main battery. You will need a UBEC if you don't know this already.

J
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Old Feb 19, 2012, 01:58 AM
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Waiting on her all new Wicked power plant thanks for asking!
The mailman brought me a new box today... this one from Ohio... and contained two 4000kV Wicked Plus EDF motors (and a new fan housing -- thanks again Don!). On 4S, Don was guessing that these will pull about 700W each... so hopefully that's gonna be enough to keep this bird in the air this time.

Sorry I haven't posted any new pics in the past few days... but that silly "work" thingy kept getting in the way. I haven't stopped working on Habu #2, just slowed down a bit... this week, I've gotten the trust tubes and centering rings all made up and painted. I also spent a fair amount of time searching for a different set of main gear retracts... and think I found a pair of servo-less retracts. They're just slightly larger than the current retract mounting recess, but I think a quick tap of the Dremel and a thin piece of plywood will give me all of the clearance that I need. Tomorrow, I plan to get the new motors mounted/balanced and then installed with the trust tubes... will post new pics as soon as I get around to getting the work done.
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Old Feb 19, 2012, 02:15 AM
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hi Kennamer,

ah ok, are we able to modify it to reverse the rotation of the fan having the thrust to push against the direction of the plane causing to brake easily? As i realise it lands really2 fast and due to the weight it would just glide across the runaway and beyond.

and where can i get the programming card for that particular ESC that i bought?

Yup im using an external receiver pack only, or do i still need a UBEC?

Thanks mate!
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Old Feb 19, 2012, 02:55 AM
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Kenzo - Yeah I would love a sortie with a couple Habu's!

Cobra68 - Awesome! I should be getting my package here shortly I imagine. My main concern is getting the thrust tubes installed correctly. For whatever reason, I have had a whale of a time getting them installed and couldn't seem to understand how to do it correctly. Hopefully the third time's the charm.
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Old Feb 19, 2012, 03:09 AM
I always find software bugs!
United States, AZ
Joined Nov 2010
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Kenzo77,

I don't think the ESC you bought has 'reverse'. That is what you would need to slow the plane down with reverse thrust.

It isn't NECESSARY, but a UBEC is substantially lighter than a separate battery pack for the receiver and servos. It appears you may want all the help you can get in the weight department!

J

P.S. I looked around briefly, and couldn't find anything that specifically states what programming card to use. It appears that you can program that model using the beep method however.
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Last edited by Kennamer; Feb 19, 2012 at 03:31 AM.
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Old Feb 19, 2012, 03:15 AM
I always find software bugs!
United States, AZ
Joined Nov 2010
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Cobra68,

Are you really a test pilot and can you get me a ride in anything? I used to work A-shop on F-15's in the AF, but never got an 'incentive ride'. They only gave them to the @$$-kissers!

What do you fly (if you are at liberty to discuss)?

J
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Old Feb 19, 2012, 04:02 AM
Build'm,Fly'm,Crash'm
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Sacramento CA
Joined Oct 2009
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Originally Posted by Kenzo77 View Post
Hey guys!

Thanks and well i haven't get to weight it yet since the ESC and the batts havent arrive.
What about the one you say you hit the curb with...that's OK, don't need that info now...the reason I ask about the weight is, if your model goes over 48 ounces, which is 16 ounces over the stock spec, then it'll fly like a tank and will not tolerate many mistakes...even small ones. Wing loading is the issue.

I don't know what it is about this model, even trying very hard to stay light, we're 14 ounces over the limit, too. We can't fly any slower than about 50 mph, or it threatens stall...landings are hairball at this weight and high low-end speed.

BTW, am I right that this is your entry model into RC airplanes?

Joe
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Old Feb 19, 2012, 04:06 AM
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Kennamer,

yea mate i really do need help haha! I am looking for a weighing scale with those digital read outs but its just too pricey over here. I only have my GF weighting scale and those are the crappy ones that is use to weight herself lol

Anyways both my EDF units are parallel with the main landing gear unit, is the nose of the plane gonna be heavy? i am gona be using 2250mAh, 4S 65-130C turnigy nano-tech batts.

im trying to get 3.5kg of thrust, is it possible since the edf each unit are rated up to 1.7-1.8kg of thrust. Sufficient for taking off?
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Old Feb 19, 2012, 04:33 AM
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Redlite,

when it was stock, yea i did hit the curb lol, and after the front end repair i tried again but the fan broke in pieces so now i had it all rip out for surgical with new EDF, ESC and new batteries.

Yea its the first plane i got, the guy told me its a very easy plane to fly, till i realise after that it was hard as hell to get it up in the air. So i got the F18 which is super lightweight and really easy to fly and assemble took me 15 mins.

But dem the bird is such a beautiful plane! cant resist it, its soo easy to fly the f18 but havent tried the sr71 yet.
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