WattFlyer RC Electric Flight Forums - Discuss radio control eflight

WattFlyer RC Electric Flight Forums - Discuss radio control eflight (http://www.Wattflyer.com/forums/index.php)
-   Beginners (http://www.Wattflyer.com/forums/forumdisplay.php?f=7)
-   -   new to rc electric (http://www.Wattflyer.com/forums/showthread.php?t=72809)

staticdave 12-15-2013 06:31 PM

new to rc electric
 
Hi a ive been away from the hobby 10 years now. I use to fly ic back in the day. But now coming back to the hobby electric power seems to be the way foward. Am looking at getting the eflight dch beaver as my first plane.

My concern is about how togo about charging batteries on site were there is no mains..

Thanks dave

JetPlaneFlyer 12-15-2013 06:37 PM

Personally I get around that issue by buying enough batteries to keep me going for as long as I need. I just charge them at home before going flying.

You can charge off your car battery if only using small flight batteries, but do it with care if you want to avoid walking home. If charging larger batteries then you need a large deep cycle lead acid battery or even a generator for the really big stuff.

hayofstacks 12-15-2013 07:18 PM

in my opinion, the recommended power system will be marginal with that setup. I run a monster 32 on 3 cells with a 12" prop on my ultra stick that weighs up to 2.5lbs less then that beaver. its pretty asthmatic at 350 watts (100 watts a pound). with 4 cells on the same prop, it pulls over 800 watts.

to get 100 watts a pound, you would need between 450 and 600 watts for marginal performance, which would about max out the power 32 motor. e-flight motors are under rated and of good quality, so you can push them a bit past max.

in y opinion you'll be looking at 5-6 minute flight times. if your really careful, maybe 15 absolute maximum. batteries in that size are a bit expensive and take a while to charge.

if your just getting back into the hobby, id recommend going with a park flyer setup, and a 450-480 sized motor. this setup should run between a 1500-2200 mah battery, and batteries of this size cost $5-10 a piece through hobby king vs $25-30 for a larger 3300 mah battery like this plane uses. later down the road, you can y these smaller batteries together and re use them for larger models.


included. brand new the plane is $120

JetPlaneFlyer 12-15-2013 07:40 PM

The Beaver in the efite video seems to fly very nicely, presumably that's running the stock efite set up. There are several videos of them on youtube and they seem to go nice on the stock set up too.
Sure it aint no rocket ship, but hey, it's a DHC Beaver not an F-16!

If you were an experienced flyer 'back in the day' then it should come back to you pretty quick, it's like riding a bike.

staticdave 12-15-2013 08:39 PM

Yeh. Not looking for a rocket ship yet. I was upto bronze standard bk then. So an easy flier to start of with..

Its mainly scale planes am interested in not really into the small park fly models.

hayofstacks 12-16-2013 12:02 AM

I was mainly trying to think about it in a cost effectiveness area. could get a decent ready to fly setup for around $200 if you still had an old radio.

scale planes also fly like crap compared to a similar sized regular rc plane. for instance, the ultra stick is close to the same size, but weighs 1.6-2.5 lbs less with the same power system and battery, giving you more performance, flight times, and.easier to repair. I suggested the mini ultra stick.because I get 20 mins a battery and it flies just as good as the ultra stick(actually better, and I own and fly both) and on a $10 battery.

but I do understand that some of us like different styles of planes, and I simply have no interest or draw to some types of planes.

as far as charging batteries, i personally have a b6 that I love, but batteries charged at 1c balanced take 1-1.5 hours each. to fly more then a couple of flights, your looking at 3-5 batteries if you want that many flights.

kyleservicetech 12-16-2013 01:20 AM

Quote:

Originally Posted by staticdave (Post 934499)
Hi a ive been away from the hobby 10 years now. I use to fly ic back in the day. But now coming back to the hobby electric power seems to be the way foward. Am looking at getting the eflight dch beaver as my first plane.

My concern is about how togo about charging batteries on site were there is no mains..

Thanks dave

Here is a whole bunch of threads for models of this size.

For the most part, you'd want a minimum of about 100 watts per pound of airplane, so that would require about a 600 watt motor up front. Running 600 watts off of a three cell LiPo would be pulling about 60 Amps out of your battery. That's a bit steep for a smaller sized LiPo. I'd be inclined to go to a 4S or a 5S LiPo battery for this size model.

What will help you in your power selection is one of those computer programs. The one I use is www.motocalc.com, which allows you to input your models wingspan, wing area, type of model airplane (Fast, real fast, streamlined, boat anchor), a variety of motors, props and battery packs. The motocalc program will spit out how the model will fly, rate of climb, stalling speed, and a whole bunch of other stuff. The program is free for 30 days, then $39.

I've been using the $$$$ Hacker motors now for 6 years. They work very well. There is also a lot of other motors available in this power range. Some are very good, some are not worth the shipping cost to get them to your house. Even at that, most of the bottom of the line brushless motors are still a lot better than the brush type motors I, along with many other modelers used 15 years ago.

Field charging is always an issue. Buying a pile of LiPo batteries gets expensive in this battery size. Best to pick up a few good batteries, and field charge them in rotation. For that, you'll need a deep cycle battery, along with a quality LiPo charger.

I use those A123 cells. These type cells are heavier, larger, and have lower voltage output than the LiPos. On the other hand, they can be repeatedly recharged in 15 minutes, can be stored at full charge, half charge, don't matter. I'm charging mine at 10 Amps per cell with a Cellpro Powerlab 8 charger. My various 6S2P A123 battery packs are being charged at 20 Amps. Plus, these batteries have absolutely zero fire hazard.

You have to build your own battery pack to save $$$ over commercial units. Individual cells run $12 each. And, they'll pretty much last the life of your model.

Thread on 70 size glow engine conversion to electric
http://www.wattflyer.com/forums/showthread.php?t=45222

Hacker 6S2P A123 powered Models
http://www.wattflyer.com/forums/showthread.php?t=44686

Hangar 9 Kantana Model
http://www.wattflyer.com/forums/showthread.php?t=68844

Hanger 9 Twist 40 Model
http://www.wattflyer.com/forums/showthread.php?t=70548

AEAJR's Site on Electric Power
http://www.wattflyer.com/forums/showthread.php?t=18521

BEC Linear Current Rating
http://www.wattflyer.com/forums/showthread.php?t=63779

mclarkson 12-16-2013 06:12 AM

As Jetplaneflyer said, I mainly buy multiple batteries. But I rarely fly more than an hour or so. If I was at the field all day long, I'd want to be able to charge.

In the field, I charge from my car battery, but most of my batteries are 800 - 1300mAh 3-cells.

kyleservicetech 12-16-2013 06:19 AM

Quote:

Originally Posted by mclarkson (Post 934558)
As Jetplaneflyer said, I mainly buy multiple batteries. But I rarely fly more than an hour or so. If I was at the field all day long, I'd want to be able to charge.

In the field, I charge from my car battery, but most of my batteries are 800 - 1300mAh 3-cells.


IMHO, working with batteries of this size wouldn't be a problem with your car battery as a power source. Charging a 3S 1.3 Amp Hour LiPo would be pulling about an amp and a half out of your car battery, about what your radio might pull.

Going to the larger 6S 5000 Mah batteries though, and you might have to take along a spare battery to start your car after you kill its battery!


All times are GMT +1. The time now is 03:35 PM.

Powered by: vBulletin
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 WattfFlyer.com
RCU Eflight HQ

Page generated in 0.08294 seconds with 13 queries