RCU Forums

RCU Forums (https://www.rcuniverse.com/forum/)
-   E-Flight Power Sources (https://www.rcuniverse.com/forum/e-flight-power-sources-126/)
-   -   NEED HELP FAST (https://www.rcuniverse.com/forum/e-flight-power-sources-126/1496414-need-help-fast.html)

airmcn_2 02-04-2004 12:49 PM

NEED HELP FAST
 
i HAVE A JETI MODEL JES 140COMPACT I NEED TO KNOW WHAT MOTOR AND WHAT POWER SORCE i CAN USE FOR A 18oz MODEL
thanks Chris

Dr Kiwi 02-04-2004 01:15 PM

RE: NEED HELP FAST
 
That ESC is designed to fit on a Speed 400 so that's a start. If it is a trainer type aircraft fit a 4:1 gearbox to a 7.2v Speed400, an 11x5.5 prop, 8-cell KAN 650's and get about 12-15oz thrust at about 7A draw. If its a hotliner, go direct drive with a 6x3 folder on a 6v Speed 400. [10-12oz thrust @ 12A].

Cheers, Phil

airmcn_2 02-04-2004 01:40 PM

RE: NEED HELP FAST
 
ok, thanks for the info what I have is a fome edge 540 that I scratch built it weighs about 18oz my goal is to fly in my back yard and still be able to do 3D So like I said I already have a JES140 compact speed cont. and a Mpi mx-6800 reciever and 3 micro servos, all I need is a brushed motor and power source, now what do you think I need
Thanks Chris

Dr Kiwi 02-04-2004 04:15 PM

RE: NEED HELP FAST
 
Hi Chris - I don't want to put you wrong here, but I think you could do well with a 7.2v Speed 400 geared 4.1:1 and run it on 3s Lipoly (or 8 KAN 650's if you don't want to deal with Lipoly) - just make sure you are not pushing any more than 8A through the system (maybe a 10x6 HD prop would be good).

Cheers, Phil

Dr Kiwi 02-04-2004 04:47 PM

RE: NEED HELP FAST
 
Hey, Chris - I think I have hit on a good combo, right off the bat! I didn't have a 7.2v 400 set up in a 4.09:1 box, but I did have a 6v 400 [ It hadn't been turned over in two years so it was pretty gummed up and its performance would surely have been better if I'd cleaned and greased the gearbox!]:

Tried it on 3s TP 2100 Lipolys with a GWS HD 10x6:

7.3A*, 10.8v, 82W, 5700 rpm, 410g (14.4oz) static thrust, 5.0g/W

Now surely THAT would work in an 18oz foam Edge 340 and that current draw is well within the motor's limits. I don't have any KAN's charged up, but I'll try some later.

Cheers, Phil

Dr Kiwi 02-04-2004 06:19 PM

RE: NEED HELP FAST
 
Hi Chris - last item of the day. I ran the 6v 400 4.09:1 with the 10x6 HD on 8-cell KAN 950's , freshly charged.

7.0A*, 10.1v, 71W, 5340 rpm, 350g (12.32oz) static thrust, 4.93g/W

That's pretty close to what you'd get with KAN 650's too.

From my old data sheets I found a run with an 11x7 HD:

9.6A*, 10.8v, 106W, 5010 rpm, 508g (17.9oz) static thrust, 4.8g/W

That is, I think, far too much to push through a 6v 400! Its life will be "nasty, short and brutish".

Whether you go for NiMh or Lipoly, the 6v Speed 400 with a 10x6 HD seems to be a good choice.

Cheers, Phil

Matt Kirsch 02-05-2004 09:48 AM

RE: NEED HELP FAST
 
If that 18oz is the plane only, you're not going to get 3D performance from a Speed 400. Slow-flyer is about the best you can expect.

For 3D, you need a thrust to weight ratio better than 1:1. Dr Kiwi has presented some excellent power combos, but none of them will come close to powering an 18oz+ plane straight up.

airmcn_2 02-05-2004 10:10 AM

RE: NEED HELP FAST
 
NO THE AIRPLANE RIGHT NOW WITH ELECTRONICS BUT NO BATT OR MOTOR WEIGHS 9oz IM THINKING THAT i WOULD LIKE TO GO WITH LIPO BATT. SO NOW WHAT DO YOU SUGGEST?

airmcn_2 02-05-2004 10:11 AM

RE: NEED HELP FAST
 
THANKS FOR ALL THE INFO EVERYBODY CHIRS


All times are GMT -8. The time now is 08:20 AM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.