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Old Jun 21, 2012, 05:45 PM
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Maple Valley, WA
Joined Apr 2006
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Thanks guys...My setup is Don's Wicked System (6404 fans, Wicked 4000 Plus motors, 60A ESCs for 1,600 watts combined). I didn't do anything to them but they have been in some crashes with that one being a gnarly nose-in impact (got it on camera). I wonder if something was thrown out of whack with that violent impact? I wouldn't even know where to begin to dynamically balance or figure out how well matched they all are in relation to each other.

You're talking about someone who JUST got a wattmeter (as a gift from a fellow member no-less) for the first time in seven years in the hobby. DOH!

The setup is coming in under 60 amps so I personally think the main problem is those junky Nanotechs I've been using. They seem fine for my prop planes but not a dual-ESC EDF.

Oh, for the record, I have yet to put my thrust tubes in and what a difference! It looked and felt about 10-15 mph slower at WOT at least. Also, I couldn't really tell much difference with the washout (or is that wash-in?) mod but the fact that she flew and landed in one piece has to be some points in its favor.
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Old Jun 21, 2012, 05:56 PM
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United States, FL, Sebring
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Quote:
Originally Posted by Aros View Post
Thanks guys...My setup is Don's Wicked System (6404 fans, Wicked 4000 Plus motors, 60A ESCs for 1,600 watts combined). I didn't do anything to them but they have been in some crashes with that one being a gnarly nose-in impact (got it on camera). I wonder if something was thrown out of whack with that violent impact? I wouldn't even know where to begin to dynamically balance or figure out how well matched they all are in relation to each other.

You're talking about someone who JUST got a wattmeter (as a gift from a fellow member no-less) for the first time in seven years in the hobby. DOH!

The setup is coming in under 60 amps so I personally think the main problem is those junky Nanotechs I've been using. They seem fine for my prop planes but not a dual-ESC EDF.

Oh, for the record, I have yet to put my thrust tubes in and what a difference! It looked and felt about 10-15 mph slower at WOT at least. Also, I couldn't really tell much difference with the washout (or is that wash-in?) mod but the fact that she flew and landed in one piece has to be some points in its favor.
The setup being just under 60 amps....... something is not quite right. Each ONE of those on 4s should be close to 60A in a 6404 fan.

This is from Don's website:
Wicked EDF motor test data (only the Wicked 4000 Plus EDF motor is recommended for this fan due to the high rotor load):
Wicked 4000 Plus Motor:
4S 2200mah 40C Skylipo: 830 watts, 60.9 amps, 13.63 volts

Evidently your lipo wasn't up to the task.
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Old Jun 21, 2012, 06:16 PM
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Yikes, what will a 3300 30C Turnigy act like then? So Don, I think I need you to chime in here...Am I missing something with the setup?
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Old Jun 21, 2012, 06:20 PM
Wonderfully Wicked
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Willoughby, Ohio
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Each setup is ~800 watts for 1600 total which is ~120 amps for the pair. You wanted the max power I had so you got it

As far as puffing, I owned 2 Nanotechs and both puffed right away, and my Blue Lipos also puffed after several flights. So right now I only use the Sky Lipos from Hobbypartz and they seem to be fine now for about a year, I use the 30C and 40C packs they sell. One thing on EDF lipos I have found is that if you ever fly them down below say 3.4 volts under no load they will puff on you within a few flights after that has happened. So that is why I fly by timer only, so my no load voltage is 3.6 or higher. Once you dip below that you run a risk and so far the Nanotech and Blue Lipo were the worst at this and I found the threshold to be about 3.4 volts at rest. I have gone down to 3.4 on Skylipos and they have not puffed on me but that happened only once or twice as I am so paranoid to fly a lipo too long now since I had to throw out so many puffed Blue Lipos that I flew a few seconds too long. The difference between 3.6 at rest and 3.4 at rest can be about 20 seconds with these high C lipos. So that is why I fly by timer and when the timer starts beeping about 15 seconds ahead of time for my warning, I immediately start my landing setup and throttle back.
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Old Jun 21, 2012, 06:30 PM
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Salt Lake City Utah
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Wow! That is over double what I ran mine at. I can see why the NanoNano tech. puffed. Maybe drop down to 3s?? Lighter, cheaper. Could use two 2200 paired together. You would still be prob. close to 1 Kw.

I've only had one Nanotech 3300 4s and it puffed at 50 amps on a warm day. No more NanoNano for me but some have liked them.

120 amps! You guys are bad boys for sure -- Stacker
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Old Jun 21, 2012, 06:51 PM
Wonderfully Wicked
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Willoughby, Ohio
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On 3S you should be about ~850 total watts which is like 75 ish amps so you could use a 3S 4000 30-40C and be OK. That will save you some weight.
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Old Jun 21, 2012, 07:04 PM
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I ran a fresh charge through the wattmeter and showed around 115 amps on average at WOT.

I'll check out those sky lips Don...Thanks...
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Old Jun 21, 2012, 07:11 PM
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I have a bunch of Sky lipos as well and have had great success with them.
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Old Jun 21, 2012, 07:15 PM
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Sky brand is what I'm using also right now.

I believe if you order from HobbyPartz they have free shipping over 50.

--Stacker
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Old Jun 21, 2012, 10:48 PM
Build'm,Fly'm,Crash'm
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Sacramento CA
Joined Oct 2009
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Here you go, stack...the build that KS has done on his B-58...you may have seen this already. Nobody has done a four-engine version from this 'kit' that I know of.

http://www.rcgroups.com/forums/showthread.php?t=906009

The math to figure wing loading is done by dividing the wing surface area by the weight...or more simple, the plane weighs, say, 50 ounces...two wings on the SR, so each wing has to carry 25 ounces. The wing area is small, so the load on the wing is high.

LX's recommended weight...this includes all the stuff you put in it, batts, AB's, radio, servos, etc., adds up to 32 ounces...MJ's rec. weight is 40 ounces for the same airframe. However, it doesn't matter what the rec. weight is...the one that's the lightest will fly best and have the least problems.

Joe
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Old Jun 21, 2012, 10:56 PM
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Quote:
Originally Posted by redlite View Post
The math to figure wing loading is done by dividing the wing surface area by the weight...or more simple, the plane weighs, say, 50 ounces...two wings on the SR, so each wing has to carry 25 ounces. The wing area is small, so the load on the wing is high.
Now you're speaking my language. Thanks for the simplified explanation.

Quote:
Originally Posted by redlite View Post
LX's recommended weight...this includes all the stuff you put in it, batts, AB's, radio, servos, etc., adds up to 32 ounces...MJ's rec. weight is 40 ounces for the same airframe. However, it doesn't matter what the rec. weight is...the one that's the lightest will fly best and have the least problems.
My God, and I hear mine sits at over 50 ounces!

No wonder it's been such a PITA to hand toss! It's a wonder it even flies at all.

Even with a 4S 3300 battery which shaves off about 10 ounces from the 4000, I'm still well over the recommended AUW. I can bump it down to a 3S but that defeats the whole purpose of why I got Don's top watt setup - SPEED.

I'm at a loss as to how I go about putting her on a diet while maintaining excellent top speed.
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Old Jun 21, 2012, 11:44 PM
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Joe,
Thanks for the link. I did not realize it was the Spark's B-58 which I've watched the builds of.

Aros,
Looks like your best bet is prob. 3s. At over 850 watts it should still fly pretty good and you can experiment latter after you get slower speed stick time.

Take care -- Stacker
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Old Jun 22, 2012, 02:12 AM
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Maple Valley, WA
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I can certainly give 3S a try but I hate to have unused wattage when it's available.

On one hand, the Blackbird just doesn't look right chugging along like she's running low on fuel, but on the other, I'd rather have a Blackbird flying around at 75-80 and landing safely versus one that flies at 95+ that has unstarts throughout and lands nose down.
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Old Jun 22, 2012, 12:34 PM
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United States, WA, Ravensdale
Joined Jan 2011
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Aros,

Congrats on a successful maiden!

I was flying a 3DHS bird the other day with a motor and ESC that had previously been in a crash. I started noticing a "wierd sound" coming from the motor... and thinking that I just had a bad battery in the plane, I landed and put in a fresh pack. Running the motor up on the ground was fine, but after flying for about a minute, the motor started surging again (much like the sounds that you alluded to in your video). So, I landed and took the plane home for a further investigation.

First, I swapped out the motor... then ran it for about a minute on my driveway... same thing started happening... So, I swapped out the ESC and the problem went away.

I can't say for certain that your issue was an ESC related problem -- but it might be something to look at before you fly again. If you had an ESC that was running hot, either due to lack of airflow or because of high internal resistance (possibly caused by a previous crash), that might also explain the extra puffy LiPo.

Not sure if that's much help or not... but I had to throw in my .02 cents.

-Sully
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Old Jun 22, 2012, 12:51 PM
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Thanks Sully, it's certainly worth bench testing. I have some spare E-flite 60's I can test...
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