Wattflyer RC Network: RC Universe :: RCU Magazine :: RCU Forums :: RCU Classifieds :: RCU User Reviews :: RCU YouTube
Home Who's Online Calendar Today's Posts RealTime Post Spy Mark Forums Read
Go Back   WattFlyer RC Electric Flight Forums - Discuss radio control eflight > Electric R/C Airplanes > Beginners
Register Members List Wattflyer Extras Articles Search Today's Posts Mark Forums Read Social Groups

Beginners New to e-power flying? Get the low down in here from experienced e-power RC pilots!

Thank you for your support (hide ads)
Reply
 
Thread Tools Display Modes
Old 12-09-2010, 12:30 AM   #1
shanet1975
Member
 
Join Date: Jun 2007
Location: Middletown, CT
Posts: 189
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default Will I notice much more power from a 4s?

I just installed my new motor and 60a speed control in a 40 size nitro stick plane. I'm not sure what the exact motor is as I am not home. The biggest lipo I have right now is a 3s 1300. I am planning on running 4s 4000's, but haven't ordered them yet. I did try the 3s on it and it went about 1/2 way up on the throttle stick and that was all it had. Wasn't much. Will I notice mush difference between a 3s 1300 and a 4s 4000?
Thanks
shanet1975 is offline  
  Reply With Quote
Old 12-09-2010, 12:39 AM   #2
Rolling Thunder
Keep the sunny side up
 
Rolling Thunder's Avatar
 
Join Date: Aug 2008
Location: victorville california
Posts: 1,869
Thanked 199 Times in 198 Posts
iTrader: (0)
Friends: (6)
Default

Oh Yea!!!You'll notice a kick for sure.Just be sure to measure the amps 1st so you dont burn up your motor.Have a blast
Rolling Thunder is offline  
  Reply With Quote
Old 12-09-2010, 12:41 AM   #3
Xptical
Member
 
Join Date: May 2008
Location: Middle Georgia
Posts: 31
Thanked 2 Times in 2 Posts
iTrader: (0)
Friends: (0)
Default

Not sure what motor/prop combo you are running. It might help if you post those.

That being said, the 1300mah LiPo (assuming 30c) can only pump out around 40 amps. That might be the cause of your lack of power.

The 4s setup will give more volts and that will be reflected in a faster-spinning prop. The 4000mah will also be reflected in higher *potential* amps.
Xptical is offline  
  Reply With Quote
Old 12-09-2010, 12:44 AM   #4
shanet1975
Member
 
Join Date: Jun 2007
Location: Middletown, CT
Posts: 189
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

Here are the spec for the motor:
Rotational Speed: 1250 (kv) RPM/V Continuous Current: 45A Max. Current: 55A Input Voltage: 6 - 14.8V Max. Efficiency: 98% No Load Current: 2.0A Internal Resistance: 34m(Omega) Power: 580W Motor Weight (Motor only): 140g Motor Dimensions (Diameter x Length): 35mm x 42mm Propeller Dimensions: 10 x 4 / 8 x 7 /9 x 5 Input Battery Types: NiCd/ Nimh/ Li-po Battery Recommend Model: Airplane
I have a 10x6 prop on there now...
shanet1975 is offline  
  Reply With Quote
Old 12-09-2010, 12:45 AM   #5
tampaflyer
to the skies of tampa
 
tampaflyer's Avatar
 
Join Date: Nov 2010
Location: tampa
Posts: 333
View tampaflyer's Gallery7
Thanked 20 Times in 20 Posts
Club: trac
iTrader: (0)
Friends: (7)
Default

dont forget to make sure the esc is rated for the 4c. and watch your discharge if you don't reset the cut off to 4 cell.
tampaflyer is offline  
  Reply With Quote
Old 12-09-2010, 12:50 AM   #6
shanet1975
Member
 
Join Date: Jun 2007
Location: Middletown, CT
Posts: 189
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

It's rated for up to 4s. I set the cutoff for the 3s as that is what I tested, but I will change to 4s when I get them. Has a built in bec as well.
shanet1975 is offline  
  Reply With Quote
Old 12-09-2010, 12:52 AM   #7
tampaflyer
to the skies of tampa
 
tampaflyer's Avatar
 
Join Date: Nov 2010
Location: tampa
Posts: 333
View tampaflyer's Gallery7
Thanked 20 Times in 20 Posts
Club: trac
iTrader: (0)
Friends: (7)
Default

ist not an eflight .. some rate to 4c but no bec at 4c only 3c...
tampaflyer is offline  
  Reply With Quote
Old 12-09-2010, 12:56 AM   #8
shanet1975
Member
 
Join Date: Jun 2007
Location: Middletown, CT
Posts: 189
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

I think I am confusing my S's and C's. Here are the specs for the 60 Amp esc:
Advantage of the Speed Controller
Low resistence
High rate PWM
Sixteen cells Max
Low torque start
Soft start ramp up
User programmable brake
Auto motor cutoff with reset
Throttle range self-adjusting
Auto shut down when signal is lost
Low voltage auto setting based on battery
Safe power arming program ensures motor will not run accidentally after turn on
shanet1975 is offline  
  Reply With Quote
Old 12-09-2010, 12:57 AM   #9
shanet1975
Member
 
Join Date: Jun 2007
Location: Middletown, CT
Posts: 189
Thanked 1 Time in 1 Post
iTrader: (0)
Friends: (0)
Default

Might be easier if I just post the ebay link. Hope this isn't illegal:
http://cgi.ebay.com/ws/eBayISAPI.dll...K%3AMEWNX%3AIT
shanet1975 is offline  
  Reply With Quote
Old 12-09-2010, 01:06 AM   #10
Rolling Thunder
Keep the sunny side up
 
Rolling Thunder's Avatar
 
Join Date: Aug 2008
Location: victorville california
Posts: 1,869
Thanked 199 Times in 198 Posts
iTrader: (0)
Friends: (6)
Default

I pull 40 amps on my 40size spacewalker using a 4cell 5000mah battery & a 11x5.5 prop.Obviously if you use a bigger prop the amps will go up.


Attached Thumbnails
Click image for larger version

Name:	011.jpg
Views:	66
Size:	109.7 KB
ID:	140402
Rolling Thunder is offline  
  Reply With Quote
Old 12-09-2010, 01:43 AM   #11
kyleservicetech
Dennis V
 
kyleservicetech's Avatar
 
Join Date: Apr 2008
Location: Wisconsin, USA
Posts: 7,870
Thanked 670 Times in 653 Posts
Club: www.racinercclub.com (I'm the newsletter editor)
Awards Showcase

Outstanding Contributor Award  3kW  2kW  100mph Speed Demon 
iTrader: (1)
Friends: (20)
Default

Originally Posted by shanet1975 View Post
I just installed my new motor and 60a speed control in a 40 size nitro stick plane. I'm not sure what the exact motor is as I am not home. The biggest lipo I have right now is a 3s 1300. I am planning on running 4s 4000's, but haven't ordered them yet. I did try the 3s on it and it went about 1/2 way up on the throttle stick and that was all it had. Wasn't much. Will I notice mush difference between a 3s 1300 and a 4s 4000?
Thanks
Don't know what brand of motor you have, but your notes indicate it weighs in at around 5 ounces. For a rough rule of thumb, anything over 100 watts per ounce of motor weight is kind of pushing the motor.

Don't know where that 98% efficiency comes from though, even the top of the line Hacker motors have trouble reaching 90%.

I used www.motocalc.com (Free for 30 days, $39 after that) to check on things. Per www.motocalc.com, this motor is not particularly efficient, running only about 70% efficient on 3 Lipos, and 54% efficiency on 4 Lipos, using your 10X6 prop. Because of the awful drop in efficiency, you might not notice a big difference between 3 and 4 cells.

Check out the Hacker A40-10S motor. (It weighs in at 9.4 ounces) Its winding resistance is only 7 milliohms, nearly 5 times less than your motor. Motocalc indicates on the same 10X6 prop, it will pull 38 amps out of your Lipo with three cells, for 360 watts. Bump that up to 4 Lipo cells, and this same motor will pull 63 Amps out of your Lipo for 820 Watts. Four cells will put out over 100 ounces of thrust. This gives a pitch speed of about 70 MPH, with around 12,000 RPM on the motor.

I've got seven Hacker motors, ranging from their A30 series, to a new A60-16M, rated for 10 Lipos, and around 2200 watts. All perform exactly per the Hacker specs. Most of my motors are three years old now, several of them have over 200 flights on them, with zero problems of any sort. (Nope don't work for Hacker, or motocalc, just like their stuff)

If you are not after a particularly fast model suggest you go to a Hacker A40-14S or other winds for a lower KV rating.

Other motors are also available such as the Scorpions and similar. Some of these motors are rather over rated by their (China) vendors. You can check them out in motocalc before buying anything.

Good luck!
kyleservicetech is online now  
  Reply With Quote
Old 12-09-2010, 03:37 AM   #12
Rolling Thunder
Keep the sunny side up
 
Rolling Thunder's Avatar
 
Join Date: Aug 2008
Location: victorville california
Posts: 1,869
Thanked 199 Times in 198 Posts
iTrader: (0)
Friends: (6)
Default

well there you have it...
a very well thought out & educated answer & a uneducated fly by the seat of your pants answer(me)
now get that battery in there & give us the answer
Rolling Thunder is offline  
  Reply With Quote
Reply

  WattFlyer RC Electric Flight Forums - Discuss radio control eflight > Electric R/C Airplanes > Beginners

« Previous Thread | Next Thread »

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 06:06 AM.


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

Charities we support Select: Yorkie Rescue  ::  Crohn's & Colitis Foundation



Page generated in 0.27721 seconds with 43 queries