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Author Topic: Gearbox or not to Gearbox!  (Read 1687 times)

ojays

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Gearbox or not to Gearbox!
« on: January 27, 2013, 11:49:41 am »

Over to you guys again.
I would appreciate your views on the following if possible, but could you keep it simple just like me please.
Originally I was proposing to fit 3 400 brushed motors direct drive to the 32mm scale props on my 1/35 Schnellboote + speed controllers of course.
However I have just found several 3.5-1  280/300 motors and gearboxes, left over from my flying days in my spares box.
Would these be suitable to use as they take up far less room than the 400 cans.
Thanks in advance
Gregg
 
 
 
 
 
 
 
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Shipmate60

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Re: Gearbox or not to Gearbox!
« Reply #1 on: January 27, 2013, 02:22:49 pm »

I would go direct drive as the gearbox will reduce the speed but increase the torque.
As this is a fast launch speed will be better for the size of props.

Bob
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Tug

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Re: Gearbox or not to Gearbox!
« Reply #2 on: January 27, 2013, 07:33:28 pm »

And of course gearboxes 3 make velly much noise  ok2

use two the same with centre motor much bigger but straight through,
on main is good for stealth but when I say go all hell breaks loose.
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nick_75au

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Re: Gearbox or not to Gearbox!
« Reply #3 on: January 28, 2013, 01:05:11 am »

It will depend on the output RPM of the gearbox, 32 MM prop in a fast boat will need about 12000 RPM give or take. Over volting the smaller motors with the gearbox is a viable option providing the power is (watts) kept to within the motors limits.


Have you got the specs on the motors themselves?? or atleast a part number or model?


Speed 300
6v
1.2-6v
No Load RPM 29000
Kv 4833
Max efficiency  19500 RPM
Max efficiency  5amps


If its the above motor, run on 9 volts and kept at 3.3 amps and/or extra water-cooling added would achieve the desired result


Cheers
Nick
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ojays

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Re: Gearbox or not to Gearbox!
« Reply #4 on: February 16, 2013, 03:40:47 pm »

Thanks for all your replies/advice, going the 400 direct route as less hassle I think!
Gregg
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Martin (Admin)

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Re: Gearbox or not to Gearbox!
« Reply #5 on: February 16, 2013, 04:07:17 pm »


..... and quieter!  :-)
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