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)
-   Batteries & Chargers (http://www.Wattflyer.com/forums/forumdisplay.php?f=6)
-   -   Tell me what to buy! (http://www.Wattflyer.com/forums/showthread.php?t=73470)

MidwestRSX 04-01-2014 12:18 AM

Tell me what to buy!
 
Hey everyone,

I just ordered a NitroPlanes Aerosky B60 kit. I am looking for recommendations as to which motors, ESC's, batteries and chargers I should buy. My goal with the plane is longer flight times, not necessarily more power. I'd like to charge two batteries at once in closer to 30 minutes than an hour. Here are the specs:

Two 4011 OutRunner Brushless 900KV, Two 45amp Brushless Electronics Speed Controller, 14.8v 3600mah 25c Li-Po.

With the goal in mind of longer flight times, what would you guys recommend?

Also, this plane does not have counter-rotating props. I would prefer it did, and since I'm starting from scratch I figured I could make that happen.. I'm assuming they make spinners and props cut in both directions..

Thanks for all your help!

xmech2k 04-01-2014 01:37 AM

Nice plane!

I know you may not like this answer, but it would take so long to explain the information that's already in here: http://www.wattflyer.com/forums/showthread.php?t=31071

Some short answers. For more flight time you need more mAh, it's like a bigger fuel tank. Of course that's bigger batteries and more weight, so it turns into a balancing act. Will they fit, will I stay in CG, and am I willing to take the added weight penalty? We can't tell you exactly what battery to get, unless someone here already has the plane and tried.

To charge batteries quickly, you first need batteries that can handle it, so you have to read that about the individual battery. For ~30 minute charge times you need at least 2C charge rate. And as far as I know, quick charging will shorten the life of batteries. You'll also need a charger that can put out some serious wattage, and probably a power supply to feed it.

Good luck and enjoy that plane. Looks beautiful!

MidwestRSX 04-01-2014 01:55 AM

Thanks for that link!

CHELLIE 04-01-2014 02:35 AM

Hi :ws: Nitro Planes does not sell the 4011 900 kv motor :( You will have to find the size of that motor dia and case Length and 900 kv and use a same size replacement motor. I will try to find you a comparable motor at Heads Up Rc.

B60 Duke Twin Engine Plane Review All About Homemade Doggie ...

marketingmanagement.ws › Doggie-Treats › video‎
The twin 9.5x7" props are spun by two brushless outrunner motors. Two 45amp ... Author: nitroplanes ... Specs says 4011 900kv but you guys don' sell that.

dahawk 04-01-2014 02:37 AM

Midwest,

Welcome to Wattflyer. We've been expecting you.

What xmech said !

The setup you have is nice, Who doesn't like the Duke?

Very nice twin. I have a Deuces Wild with twin Scorpion 710's and run 4000mah 4S 40C's. But I have 2 battery compartments. Have a Freewing Mossy that takes one lipo and use a 4S 3600mah 40C for about 6 min and I tend to be heavy on the throttle.

So, how much flight time are you looking for?

Here's a suggestion that may or may not work for you.. Measure the cabin space. See if you can get two 2400- 2650 mah 40C's in there, side by side. Individually they will be thinner and together maybe same size as your 3600. You then connect them to a parallel adaptor like these:

http://www.headsuphobby.com/Parallel...ness-C-760.htm

http://www.buddyrc.com/t-plug-parallel-adapter.html

You get the same voltage but 2X the mah. So in my example, you would get 5300mah

I now get my lipos from China hobby Line www.chinahobbyline.com

Great prices, service, quality, free shipping on orders over $50, US warehouse . Nice dimensions.

Lets us know how you like the B60 !

-Hawk

CHELLIE 04-01-2014 02:57 AM

http://static.rcgroups.net/forums/at...g?d=1348963934



Hmmmmm ????

http://www.rcgroups.com/forums/showt...1742424&page=3


Views: 75

Angled view, if you see the silver inside the air vent, that is the motor mount. the motor is very short. I have never seen a 4S motor this short before.

The Bell Diameter is 41mm, or 1.6 inches
Shaft length behind motor is 19 mm or inches
Motor front to back is 19 mm or inches

http://static.rcgroups.net/forums/at...g?d=1349276085

MidwestRSX 04-01-2014 04:20 AM

Quote:

Originally Posted by CHELLIE (Post 944183)
Hi :ws: Nitro Planes does not sell the 4011 900 kv motor :( You will have to find the size of that motor dia and case Length and 900 kv and use a same size replacement motor. I will try to find you a comparable motor at Heads Up Rc.

B60 Duke Twin Engine Plane Review All About Homemade Doggie ...

marketingmanagement.ws Doggie-Treats video‎
The twin 9.5x7" props are spun by two brushless outrunner motors. Two 45amp ... Author: nitroplanes ... Specs says 4011 900kv but you guys don' sell that.

I've been looking at the E-flite power 25, Rimfire .15 or .25, or the Turnigy G15.. kinda leaning towards Turnigy because of the price.

MidwestRSX 04-01-2014 04:25 AM

Quote:

Originally Posted by dahawk (Post 944185)
Midwest,

Welcome to Wattflyer. We've been expecting you.

What xmech said !

The setup you have is nice, Who doesn't like the Duke?

Very nice twin. I have a Deuces Wild with twin Scorpion 710's and run 4000mah 4S 40C's. But I have 2 battery compartments. Have a Freewing Mossy that takes one lipo and use a 4S 3600mah 40C for about 6 min and I tend to be heavy on the throttle.

So, how much flight time are you looking for?

Here's a suggestion that may or may not work for you.. Measure the cabin space. See if you can get two 2400- 2650 mah 40C's in there, side by side. Individually they will be thinner and together maybe same size as your 3600. You then connect them to a parallel adaptor like these:

http://www.headsuphobby.com/Parallel...ness-C-760.htm

http://www.buddyrc.com/t-plug-parallel-adapter.html

You get the same voltage but 2X the mah. So in my example, you would get 5300mah

I now get my lipos from China hobby Line www.chinahobbyline.com

Great prices, service, quality, free shipping on orders over $50, US warehouse . Nice dimensions.

Lets us know how you like the B60 !

-Hawk

I think I'm going to shoot for a single 4000 - 4400 mah batt. I'm also trying to stay away from budget batteries, I want to get ones that will last. I've been looking at Gen's Ace, Hyperion and SPC. Any thoughts? Are those and ChinaHobbyLine batts comparable to name brand ones? I was thinking about going with more powerful motors, allowing me to cruise around at lower throttle and maybe be more efficient. I don't know if that or smaller motors at slightly higher rpm would be more efficient. I'd like to get over 10 minutes for sure, ideally closer to to 15. I don't know if that's reasonable..

MidwestRSX 04-01-2014 04:28 AM

Also, I am concerned about making sure I don't burn up motors by using the wrong prop/motor/battery combo. The kit calls for 9.5-10/7 3 bladers.

Also, any thoughts about counter-rotating props?

MidwestRSX 04-01-2014 04:43 AM

[QUOTE=dahawk;944185]Midwest,

I have a Deuces Wild with twin Scorpion 710's and run 4000mah 4S 40C's. /QUOTE]

Those Scorpions are more than I'm looking to spend on motors. Is there a big difference between Scorpion, E-flite, Rimfire and Turnigy? I was thinking about skimping on the motors before skimping on batteries.

fhhuber 04-01-2014 06:01 AM

You will find assorted reviews of the assorted Turnigy brand motors. Sme they make are really good. Some are junk. I've got examples of both.

I have a PAIR of 12S 100 amp rated Turnigy motors that they used low temp "hot melt" glue to install the magnets... 120 deg F and the magnets move.

I have a few smaller Turnigy motors that are just fine and have no issues at 180F by thermocouple between the X mount and motor.

***************

Batteries: Price does not necessarily mean quality. I have had better results from the Sky LiPo 20C packs at Nitroplanes than from Polyquest 30C packs which cost more than 4 times as much.
I use nothing but Sky LiPo now and I fly models using from 2S 500 mah to 12S 5000 mah. (12S is by putting 3X 4S or 4 X 3S in series)

(OK... I have some Parkzone micros and those I'm stuck using the Parkzone/E-Flite or Turnigy 1S 120 to 150 mah cells)

xmech2k 04-01-2014 06:06 AM

If you want to take care of your power systems, you need to get a wattmeter to see how many amps/watts they're pulling. That way you can know if they're within limits. Selecting power systems, to me, is one of the most challenging parts of this hobby.

xmech2k 04-01-2014 06:10 AM

Oh, and I see you have 2 almost identical threads going on this subject. To prevent confusion and such, it's probably a good idea to direct people to one with a shortcut and lock the other. Just good forum etiquette.

CHELLIE 04-01-2014 10:40 AM

This is the Closest motor that I have found so far that will fit into your engine Cowl, if you use another motor that has a longer can length, you will have to modify the planes motor mounts to sit back further, this motor in the ad is rated for a 3 cell lipo with a 12x6 prop, but it will handle a 9" prop on 4 cells, when you go down on the prop size, you are able to use more battery cells, a Watmeter is a must have when doing this, you will need to use a 4mm col let prop adapter.

http://www.hobbyking.com/hobbyking/s...ner_900kv.html

http://www.hobbyking.com/hobbyking/s...alog/28765.jpg

Spec.
Required Voltage: 11.1v
Max current draw: 35A
Max power: 400W
No Load Current: 1.2A
Shaft: M4 (perfectly suited to Towerpor/GWS SF Slow Fly props)
Weight: 80.0g
Diameter: 41mm
Overall length: 63mm
Kv: 900rpm/v
Comes with mount as shown in Image
Prop Test
Prop Size Voltage Ampere Thrust
12x6 11.1 23.6A 730g

CHELLIE 04-01-2014 10:46 AM

or this motor thats rated for 4 cells, only 50kv less, its a 850 kv rather than a 900kv, not much difference

http://www.hobbyking.com/hobbyking/s...ner_Motor.html

http://www.hobbyking.com/hobbyking/s.../D4023-850.jpg

Specs.
Rpm/V: 850kv
Max Watts: 380W
Max Amps: 35A
Max Volt: 7.4~14.8v (2~4S)
Idle Current: 1.5A
Resistance: 0.039 ohms
Weight: 107.1g
Shaft: 4mm x 39mm threaded
Can Size: 41mm
Mount Diameter: 30mm
Prop test.
12x6 11.1v 27A 1600g

CHELLIE 04-01-2014 11:07 AM

IMHO this would be a better motor to use
 
http://www.hobbyking.com/hobbyking/s...ner_Motor.html

http://www.hobbyking.com/hobbyking/s...090%281%29.jpg

Spec:
Model: SII-3008-1090kv
Kv: 1090rpm/v
Motor Wind: 23 Turn Delta
No Load Current: 0.79A
Motor Resistance (Rm): 0.058 Ohms
Max Continuous current: 26A
Max Power: 370w
Shaft: 4.98mm
Weight: 95g
Cell count: 4s
Outside Diameter: 37.5mm

CHELLIE 04-01-2014 11:11 AM

Quote:

Originally Posted by MidwestRSX (Post 944193)
I've been looking at the E-flite power 25, Rimfire .15 or .25, or the Turnigy G15.. kinda leaning towards Turnigy because of the price.

You will need to use the Pancake motors, rather than the longer can motors or you will have to re do the planes motor mount to make the motor fit, or the motor will stick way out of the cowl.

CHELLIE 04-01-2014 11:20 AM

The Rimfire 25 will work well, use a rimfire esc with a rimfire motor, Rimfire motors dont tend to like other MFG esc.

http://www3.towerhobbies.com/cgi-bin...?&I=LXLWV1&P=3


http://www2.gpmd.com/image/g/gpmg4675.jpg

dahawk 04-01-2014 01:47 PM

The chemistry to make lipos doesn't change much between vendors. It's like oil. QC is what makes the difference IMO. How they are actually assembled does matter. Gens Ace has a great reputation. Almost always out of stock. I think I've tried 20 brands and the only one that has let me down was Nanotech. Very happy with CHL

On motors, Chellie has listed some good ones. I always pay heed to her advice. She'll always steer you in the right direction.

I've been using the SK3 series from HK lately and they have held up nicely. Apparently made on the same line as the Hacker.

Also have good luck with the Powerups from headsuprc. The Powerup 15 might be a good option. Not such great luck with Emax but it may have been the motoree, not the motor.

http://www.headsuphobby.com/Power-Up...otor-E-575.htm

Rule of thumb I learned from Chellie is 150 watts per pound. (2) 15's would yield 1100 watts which would be ample for a 7 pound plane.

Good luck on the +10 minutes ! You may like gliders better. Just kidding.

fhhuber 04-01-2014 02:49 PM

Long duration can be easy... or very hard. The size of the model matters because the bigger the wing the more efficient it will be. (lift vs drag)

The PZ vapor is a good example of long duration on low power... very slow and light so it doesn't take much power to keep it in the air.
Double the battery (original was 90 ma single cell LiPo) and you won't quite double the flight time.
Add enough weight by adding too much battery (no other changes) and you will eventually start reducing duration because you have to use full throttle to keep it in the air.

For any electric model (don't change motor, ESC or anything else... just the battery) there is some battery which will give maximum flight time. It can take a while to find that battery...

Change anything else about the model and you may need a different battery for the maximum duration.

Without doing a lot of experimenting with the exact same airplane... we can't tell you what the best duration setup will be.

thepiper92 04-01-2014 04:58 PM

Quote:

Originally Posted by fhhuber (Post 944238)
Long duration can be easy... or very hard. The size of the model matters because the bigger the wing the more efficient it will be. (lift vs drag)

The PZ vapor is a good example of long duration on low power... very slow and light so it doesn't take much power to keep it in the air.
Double the battery (original was 90 ma single cell LiPo) and you won't quite double the flight time.
Add enough weight by adding too much battery (no other changes) and you will eventually start reducing duration because you have to use full throttle to keep it in the air.

For any electric model (don't change motor, ESC or anything else... just the battery) there is some battery which will give maximum flight time. It can take a while to find that battery...

Change anything else about the model and you may need a different battery for the maximum duration.

Without doing a lot of experimenting with the exact same airplane... we can't tell you what the best duration setup will be.

Agreed, it is not something easy to figure out without experimentation, or figuring out every thing mathematically, and there are so many factors. Also if you start going to big, you have to carve the fuse out possibly. This can weaken the plane if you aren't careful, of course depending on where the battery is installed.

MidwestRSX 04-02-2014 02:37 AM

Thanks for all the responses everyone. Here is what I have going so far: Gens Ace 3800 mah 25C; Turnigy G25 or Rimifire 25, leaning towards Rimfire (do those come with the mounts as well?); Rimfire 45A ESC's; 10 x 7 props, and the iCharger 208B with a 12V power supply.

thepiper92 04-02-2014 02:59 AM

You could go to a lower prop pitch. Higher pitch means longer take offs and higher speed, thus pulling more amps.

MidwestRSX 04-02-2014 03:35 AM

Do I need to get a wattmeter? Is there a formula or a way to calculate draw so I know what to buy to be safe?

kyleservicetech 04-02-2014 04:36 AM

Quote:

Originally Posted by MidwestRSX (Post 944320)
Do I need to get a wattmeter? Is there a formula or a way to calculate draw so I know what to buy to be safe?

Naw

Buy a wattmeter!

Another option is a digital AC AND DC clamp on ammeter, such as the Sears Craftsman #82369 unit. Note that most clamp on ammeters are AC only, not useful for our DC battery powered models. This #82369 meter can measure the current pulled by any model from a small foamie to a giant scale 15,000 watt model. (Or even the starter current on your car) And, it doesn't require using plug adapters for between the battery and ESC.
http://www.sears.com/craftsman-digit...p-03482369000P

One of the quality programs out there for calculating this stuff is www.motocalc.com. (There are also a number of free programs.) And, even this program is only as accurate as the motor specifications provided by the mfg.

I've found those motor specs can be off by 50% on some product lines.


All times are GMT +1. The time now is 02:16 AM.

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

Page generated in 0.10722 seconds with 13 queries