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Author Topic: Motors + ESC + Lipo. Help.  (Read 2099 times)

freko16

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Motors + ESC + Lipo. Help.
« on: March 14, 2016, 03:32:43 PM »

Hi, I am building a boat with twin screws, I am using 2 x Turnigy 2836- 1200 motors 2x Turnigy 1/8 scale 120A Waterproof ESC, 2x Turnigy 5.0 4cell 14.8 Lipo's , My problem is as soon as I move the transmitter stick it goes into nearly full speed I have only wired them as independent sides at the moment just to try them out , I have tried with the  the programmer box and with the transmitter both give the same results, I have already burnt out one motor and replaced it I do not want to do that again, I am a real newby with this so any help and advice would be very welcome. Regards freko16
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nivapilot

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Re: Motors + ESC + Lipo. Help.
« Reply #1 on: March 14, 2016, 05:44:00 PM »

Sounds like the ESC needs programming or setting up.?
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freko16

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Re: Motors + ESC + Lipo. Help.
« Reply #2 on: March 15, 2016, 07:15:28 AM »

Hi Nivapilot, Thanks for reply, I have tried all sorts of programs with the programmer, it just seems to be the same whatever i put in, it does go forward stops in centre position and goes into reverse all at high speed, I tried programming it with the transmitter all the same, I have been in contact with H/King they could not provide an answer apart from sending them back, this is the second batch of ESC'S I have had from them the first lot were boat ESC, they behaved much the same. Regards freko16.
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craggle

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Re: Motors + ESC + Lipo. Help.
« Reply #3 on: March 15, 2016, 09:12:30 AM »

What type of boat is it and what diameter are the props?

The motors seem very high KV to me to be running on 14.8V At full speed a 1200Kv motor on 14.8v will be spinning at 17760 rpm.

I have just bought motors for my lifeboat and got 4s, 14.8V batteries and Turnigy 120A Marine speed controllers but I'm using 400Kv motors. These spin from a couple of hundred rpm up to nearly 6000rpm at full speed.

Craig.
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canabus

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Re: Motors + ESC + Lipo. Help.
« Reply #4 on: March 15, 2016, 10:16:34 AM »

These motors are OK on small prop 30mm 2 blade , but, if the props are larger the motor's will fry!!
For prop from 35 to 60mm 2 more blades the 35mm 3639-750, 3639-1100 or a 3648-1450 on 3 or 4S Lipo batteries.
I have used 37mm 3blade, 40mm 2 blade and 45mm 2 blade on these motors.
The ESC I use is only 60 Amp but no fried ESC's or motors in 2 years.
Also never used a water cooled mount just alloy home made mounts.
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freko16

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Re: Motors + ESC + Lipo. Help.
« Reply #5 on: March 15, 2016, 06:01:36 PM »

Hi All, Thanks for replies, The boat is 34.5 RAF Crash Tender, the props measure about 32mm 3 bladed, I did think that the motors might be the problem, I am looking at Turnigy G46 420 kv , What were the motors you installed Craig ?. Regards Ken.
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craggle

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Re: Motors + ESC + Lipo. Help.
« Reply #6 on: March 16, 2016, 08:29:37 AM »

My boat is a 1:12th scale Severn lifeboat so quite a big model. Props must be around 60mm or so.

The motors I'm using are Turnigy L5055A 400Kv 1400w versions along with their 120A water cooled marine speed controllers.
Shame you don't live closer to me or I could pop over with a motor and try it before you have to buy.

Craig.
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freko16

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Re: Motors + ESC + Lipo. Help.
« Reply #7 on: March 16, 2016, 09:34:21 AM »

Thanks Craig, I think I will just buy one motor to see how it goes, thanks again for your help. Regards Ken.
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craggle

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Re: Motors + ESC + Lipo. Help.
« Reply #8 on: March 16, 2016, 09:56:05 AM »

They are big motors though so be careful. 50mm diameter and quite heavy. You may be able to get away with smaller motors at the lower Kv rating.

Craig.
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freko16

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Re: Motors + ESC + Lipo. Help.
« Reply #9 on: March 16, 2016, 04:54:26 PM »

Hi Craig, I have returned the two motors to H/King hoping they will refund the cost of both, then I will look for something more suitable. Ken.
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martno1fan

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Re: Motors + ESC + Lipo. Help.
« Reply #10 on: March 22, 2016, 08:28:02 AM »

This one should work well 650 kv on 6 s would give you 11976.9 k rpm loaded and around 17 mph,set your esc to a soft start if you can,4 s would also work for 11 mph ish. even 5 s is another option.Suppose it depends what sort of speeds your wanting .



http://www.hobbyking.com/hobbyking/store/__31678__Turnigy_AquaStar_4084_620KV_Water_Cooled_Brushless_Motor.html
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spearfish99

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Re: Motors + ESC + Lipo. Help.
« Reply #11 on: March 22, 2016, 05:13:53 PM »

As you are building a crash tender, you will find that there is a wealth of info concerning what motors etc to use here

  http://model-boats.com/

  As well if using HK ESC's, you may find that some of them need the throttle channel set to reverse function on the transmitter (especially if using Futaba radio) before they appear to program properly
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