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[aamcle]

May I check that I a basic understand of the wiring of a RC boat with 2 brushed motors.


I've not included battery to RX  or speed controller just to keep it simple.
RX (4 channel)
RX to servo 1 and servo 2 ( If I use 2).
RX to speed controller (esc).
Speed Controller (2 output) to 2 individual brush motor jet drives.
I think I need to have something to keep the motors in balance if I'm going to use them on one channel. Is it a discrete component or a fancy speed controller?
The evilbay jet drives I'm looking at specify a motor voltage but not a current draw or it's KV (rpmvoltage) so how do I work out what size of speed controller I need?
Assuming I don't want a lot of speed now do I determine what batteries I need?

Can you point me to a wiring diagram for that arrangement?
Many Thanks.        Aamcle

[aamcle]

More reading and I've found what I need.


Atb.       Aamcle

[tica]

First of all welcome to the Mayhem 
You mention that you are using a set of jetdrives what boat do you have ??
I would use a Y-cable for the ESC's no mater whether it is brushed or Brushless

If it is Kehr 28mm jetdrive you should keep the max rpm at 20k, if you choose Brushless solutions the lower KV (rpm/voltage) the lower amount of A/h load, Kehr suggest approx. 500W of power for a BL motor and then it is up to you what solution of battery vs. BL/ KV  you choose.
I'm running a 1800kv BL on 3S lipo on a 28mm Kehr jet on my Palm Beach from Billing Boats and it goes like a rocket.

[aamcle]

Thanks for your reply.
.
I'm looking at no name drives from the bay, the listing gives working voltage and physical dimensions but nothing else so I don't know the rpm or stall current.
.
As for the boat well I haven't built it yet :) I'll do something simple over a foam core probably a hard chine type as they are relatively easy to make.


Many thanks.       Aamcle


Ps will the annoying verifications stop popping up or do I have to live with them forever?

[malcolmfrary]

Speed Controller (2 output) to 2 individual brush motor jet drives.
I think I need to have something to keep the motors in balance if I'm going to use them on one channel. Is it a discrete component or a fancy speed controller?

The "2 output" ESCs put out the same power to both motors.  One input from the radio, 2 output stages.
"Balance" between the two motors is a matter of hoping that both motors are equally efficient, and the same for both drives.  Even if you use two channels and an ESC for each motor and set them up to respond identically, there will always be the probability that the motors/drives will have different responses at different speeds.  With 1 ESC, the answer is to use the rudder, with 2, either the rudder or a mixer, or both.  Even if the motors and drives are perfectly matched, in the real world, a varying side wind will cause all bets to be off.

[aamcle]

Thanks All.




Aamcle

[johnv]

Hi it's John V have you got reverse buckets on your jet drives cheers John V

[aamcle]

Well I haven't and the drive arrived damage!!


This has put my plans on hold I'll have to wait for another drive to come on "the slow boat from China".






Aamcle