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View Poll Results: Are you interested in a Multiplex Sonic Liner clone?
I'd strongly consider buying one 76 54.68%
I would possibly consider buying one 31 22.30%
no interest 29 20.86%
other thoughts- explain in your post 3 2.16%
Voters: 139. You may not vote on this poll

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Old Nov 29, 2012, 10:19 PM
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One more question for Jurgen

somethng I have been wondering in the back of my mind for while, is that on brushed motors the SL cant have had much more than 180 to 200 watts of power going thru it, but it flies pretty well like that, I have a hard time imagining a brushless plane this large flying on so little power, but I have noticed that all the old brushed twins are strong fliers on very little power, what makes twin brushed motors in the multiplex line perform so strongly compared to singe brushless setups of similar wattage?
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Old Nov 30, 2012, 04:14 AM
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53859 Niederkassel, Germany
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Quote:
Originally Posted by cgoffa View Post
somethng I have been wondering in the back of my mind for while, is that on brushed motors the SL cant have had much more than 180 to 200 watts of power going thru it, but it flies pretty well like that, I have a hard time imagining a brushless plane this large flying on so little power, but I have noticed that all the old brushed twins are strong fliers on very little power, what makes twin brushed motors in the multiplex line perform so strongly compared to singe brushless setups of similar wattage?
Those Speed/Permax 400 models will fly with even less power when equipped with brushless motors. Keep in mind however, that the brushed motors run at only approx. 50% efficiency @ 10A, so ideally should be throttled back to approx. 5A (or less) in order to fly efficiently.

Jürgen
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Old Nov 30, 2012, 10:33 AM
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In other words, your 57oz model better get by on 84W (each motor drawing 5A from 8.4v) or less or your efficiency hits the floor. Yes, we have it good in the era of the brushless motor.
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Old Nov 30, 2012, 10:41 AM
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http://www.rcgroups.com/forums/showthread.php?t=1780049 this guy has one for sell in the classifieds for $300. i tried to talk him down, but he's not budging. $300 is very pricey
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Old Nov 30, 2012, 11:23 AM
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Originally Posted by gchrisgo34 View Post
http://www.rcgroups.com/forums/showthread.php?t=1780049 this guy has one for sell in the classifieds for $300. i tried to talk him down, but he's not budging. $300 is very pricey
Cool...I sent him a PM. Thanks.
Even if I do obtain an original, I'd love a clone that I wouldn't have to be so careful with.

EDIT: LPU only...so anyone who is near this guy may want to take a look. The price includes brushless motors and ESCs...so not too bad assuming he picked good motors.
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Old Dec 01, 2012, 02:27 AM
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Originally Posted by MRGTX View Post
In other words, your 57oz model better get by on 84W (each motor drawing 5A from 8.4v) or less or your efficiency hits the floor. ...
Well, at a mere load of 2 x 5A = 10A, the voltage should be at least 10V on 8 cells and 100W is plenty of power for cruising.

For comparison: http://www.rcgroups.com/forums/showp...postcount=8270

Jürgen
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Old Dec 01, 2012, 05:11 AM
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Did the 400 motors really "provide" (consume) 90-100w each? I use Turnigy SK3 2822mm 1740KV motors with 6x4.5 props, each sucking up 115W max static on 3S.

If I dared, I'd most likely get vertical out the set-up. I just tried it inside without vertical stabs, canards and wing ends, but it had no problems whatsoever hovering vertically. Adding another 140grs wouldn't have mattered, and I cannot believe that this would have been possible with the stock set-up....

Off course the higher efficiency provides more thrust per watt, but still?

BTW: It cruises nicely at half throttle

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...Even if I do obtain an original, I'd love a clone that I wouldn't have to be so careful with.
...
I know exactly what you mean!
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Old Dec 02, 2012, 12:19 PM
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Nothing to see here, move on.
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Old Dec 02, 2012, 07:05 PM
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long can 400's

The motors i use came from hobby lobby they used to make a long can speed 400 that takes 10v really well. Using the gunther props until they broke i had really good performance from them. Jurgen's explanation of power draw makes sense as i was flying nicely under 100mah per minute at cruise


QUOTE=mike_o;23410352]Did the 400 motors really "provide" (consume) 90-100w each? I use Turnigy SK3 2822mm 1740KV motors with 6x4.5 props, each sucking up 115W max static on 3S.

If I dared, I'd most likely get vertical out the set-up. I just tried it inside without vertical stabs, canards and wing ends, but it had no problems whatsoever hovering vertically. Adding another 140grs wouldn't have mattered, and I cannot believe that this would have been possible with the stock set-up....

Off course the higher efficiency provides more thrust per watt, but still?

BTW: It cruises nicely at half throttle



I know exactly what you mean![/QUOTE]
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Old Dec 03, 2012, 10:39 AM
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3d model is ready.


Amazing work, sir!!

That is a beautiful shape, isn't it?!
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Old Dec 03, 2012, 07:09 PM
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Nothing to see here, move on.
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Old Dec 04, 2012, 08:33 AM
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http://www.rcgroups.com/forums/showthread.php?t=1456055

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Old Dec 05, 2012, 12:56 AM
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i think this plane was ahead of its time! thats why it didnt sell so well. and the technology was'nt there, for what this plane really needed.
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Old Dec 05, 2012, 07:56 AM
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Originally Posted by gchrisgo34 View Post
i think this plane was ahead of its time! thats why it didnt sell so well. and the technology was'nt there, for what this plane really needed.
The model flew pretty well with the technology available back then. It just wasn't attractive enough for the average modeler to make a profit with.

Jürgen
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Old Dec 05, 2012, 11:18 AM
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Originally Posted by Darsh View Post
Indeed
Now pick your poison: would you feed the data to a cnc mill machine, or cut foam boards and assemble? If board it is, which thickness?
Wow... I don't have personal access to a CNC machine but a guy in my club claims to. If you wouldn't mind sharing the file, that would be awesome. Thanks again for putting this together and sharing your talents!!

I'm pouring over that build thread right now... incredible work.

Quote:
Originally Posted by gchrisgo34 View Post
i think this plane was ahead of its time! thats why it didnt sell so well. and the technology was'nt there, for what this plane really needed.
gchrisgo, I suspect you're right.
Besides, tastes and climates in the hobby change. For example, there is a much bigger appetite for big pusher models these days thanks to the FPV trend...and with modern computer radios and gyros, there is a lot more fun to be had with playing with thrust differential and canards.

So I agree. improved tech is one big reason why this model is looking damn good these days.
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