Twin motor setup on my 46" mono - what do you think

[Simon170]

Hi guys,

I'm new to fast electric boats but have been into RC for a lomg time so not a total newbie.
I was just wondering if I could get your thoughts on my setup, wrong, right, inderefent etc.

The boats 46" long and 11" wides, twin props. It has 2 x Leopard 4074 1050kv motors, 2 x 200amp esc's, 42mm props and I'm planning to run 2 x 6s 50c 5000mah batteries, one to each esc.

Its not a race boat, just for fun. So after a solid and reliable setup, not looking to set the world on fire (or the boat for that matter lol)

Any and all advice welcome Thank you.

[srislash]

Well that should run well. I have a 40" that has 1180kv TPpower 4074's in it and it is a hoot. You may need bigger props but starting small is a good idea.
Have you setup the ESC's? Calibrated? Lubed the cables(prop flexes)?

I run 42mm but it is on 8s too. 4800mah packs and 10 mins play time. I would venture a guess at 5-6 mins for your setup once it is tuned.
Start with balancing the hull lengthwise on a rod(dowel). With it all loaded it should balance somewhere around 14" from the transom. This is just a starting point. See if it hops going straight or hooks in a corner. Then we adjust from there. Just do a 1min run and check on things.

Shawn

[Simon170]

Thanks for the reply mate So you dont think I'm over or under powered? I was worried it would be a bit sluggish but I dont want to burn it up first time out either.
Going to do what you said, take her out as is, see how it runs and get the boat balanced, then maybe add bigger props if the temps are all ok. If the speed bug really bites I'll go 8s but will have to uprate the ESC's.

[srislash]

You would be surprised how well 42's can push a decent sized boat

https://youtu.be/6-KjgtRim_Q

[Simon170]

You would be surprised how well 42's can push a decent sized boat
https://youtu.be/6-KjgtRim_Q

Yeah but you've got 30volts behind them! Haha Nice boat, really moves out!

[srislash]

It has been a funky project. Thanks

[centralrcmystic]

I have a dual outboard 44in mono with counter rotating x442, seaking 180 amp ESC's 3630 1500kv motors and my temps are 110 degrees. You can def go up on your props if you haven't already bought them.

[Simon170]

Thread from the dead alert!

I?ve finally had the boat out and it?s awesome, really pleased with it. Went full throttle round the lake a few times and brought it back, everything was still cold so I?m now thinking bigger props as mentioned before by other members.

I?ll probably buy them from OSE, but not sure how much bigger to go, as I?m unsure how big a change each millimetre increase has. The pitch is something of a mystery to me as well.
I?ll have to post a pic and see what you guys think....

[Simon170]

Here's the boat and props...

[srislash]

How did you feel about speed and runtime?

[Simon170]

I wouldn?t mind a little more straight line, run time has been great so far.

[srislash]

I wouldn?t mind a little more straight line, run time has been great so far.

Well I would keep away from added pitch on a mono. 445’s or 447’s or something the like of. Really any diameter which is greater will increase speed.

[Steven Vaccaro]

Nice looking mono. Id first start by getting a reading on your amps. They are probably low, but you shouldn't assume.

You can do this to measure amps for an approx current draw.
This will work well with lipo packs and lipo chargers that tell you the mah put back into your pack after a charge.

Step one, fully charge your lipo pack.
Step two, run the boat for a couple of laps at full speed for an exact measured amount of time. 30 seconds is usually good.
Step three, quickly recharge the pack and take note on the amount of mah put back into the pack.
Step four, click here https://www.offshoreelectrics.com/conversion.php and plug those numbers into the first table on that webpage. Take a look around that page, there are a bunch of useful formulas there.


If the amps are about 1/2 your esc's capacity, Id jump two sizes up. If not, Id only go one size up.


one size up
https://www.offshoreelectrics.com/pr...od=cnc-4514251


two plus sizes up.
https://www.offshoreelectrics.com/pr...od=cnc-4814250
https://www.offshoreelectrics.com/pr...?prod=oct-x447