Twin electric outrigger or mono hull help with esc hook ups please!

[riggerhunter]

Hello guys, I am some what new to electric boats. I just built a rigger insanity runs great around 50mph. For the winter build I want to scratch build a twin electric rigger or mono hull, something with twin electrics.
I was going to build around a pair of leopard 3674 2200kv's, 5000 2S packs. I am wondering how to hook up with 2 esc's ( and what ones I should use). Can I hook them up with just a y harness to the receiver (2.4gz futaba 3 channel) without cutting any wires? as not to confuse the receiver? I don't know, please help with all the info you guys can give me. Also do I have to run counter rotating shafts and props? I plan on having the shafts around 4 inches apart. Thanks in advance for any help with the information.

[NativePaul]

Yes it can be as simple as a Y lead to both ESCs from the receiver, I don't know your radio but another way to do it on mine would be to mix channel3 100% with channel2 so it slaves off the throttle and does the same thing, its more complex with the programming involved but saves you the price of a Y lead if you don't have one knocking around in your flight box.

You mention 2s packs, how many? Those motors will require 4s to be FE and running both from 4s1p is a lot to ask of even the best packs, I would recommend if you are going to use 2s packs using 4 of them as either a 4s2p pack or a 4s1p pack for each ESC/motor, there are good boats that do it both ways and I don't think it really matters too much which way you go.

Rigger or Mono is a personal choice based on your aesthetic preference and what you want the boat to do, both have their good and bad points so I will leave that ball in your court, if you want advice on which to get explain as specifically as you can what you want to do with it, where and in what weather.

A mono should contra rotate, they have enough torque troubles with singles, when your putting a second in anyway why not alleviate that as opposed to adding to it? Riggers are wide enough not to have major torque problems and don't have to be contra rotating and I have heard that they turn (right) better if they aren't. the twin .90 IC riggers all use normal left handed props on both sides. If you go contra rotating and want to use flexshafts don't forget you will need a flexshaft with the cable spiral laid in the opposite direction for the right handed prop or it will unravel itself, or you can use wire drives instead.

4 inches apart is quite a long way, is there any reason for that? if you go for a mono unless it is a flat bottomed or heavy and slow so it displaces a lot, when it leans into a corner the outside prop will be out of the water and you will lose half your thrust as well as doing no good for the full throttle but free-spinning motor, and melting your strut bearings if they are lead-teflon, the problems with a wide gap on a rigger are insignificant in comparison but closer is better, a twin .90 doesn't have its struts at the extremities of the tub they are not in but approaching the middle, never measured one but looks like less than 4" and they are swinging 67mm props, much bigger than the props that your motors will swing.

[riggerhunter]

Native Paul, Thanks for getting me started. It will probably be a 60 to 90 size rigger. As of right now I have a less expensive 3 ch futaba radio no mixing so if all I need to do is y harness them together no problem. As far as the spread of the shafts well I guess I was thinking around 4" but I suppose close as I can put the motors together in the boat. How about speed controls? I will be running two 4S packs. I was thinking around 120amps each. Seakings or are they worth the money? Also I was going to cool each set up separately

[6BOOST]

Is the twin rigger just for fun? As it will be faster with a single motor than a twin? Less weight, less cost, double the run time with the same amount of batteries, all reasons to look at a slightly bigger/better single than smaller twins. Twins don't go twice as fast, maybe 5-10% better, same total rpm see, but you can go up maybe 1 prop size and twins accelerate faster due to twice as much thrust. Same with a mono, which when you run as a twin, 99% of hulls due to the design will end up having props quite high due to the shape of the V. If you want to go twins in a mono, I'd suggest looking at twin inline or a hull similar in design to the HPR Mono. Happy building=)

6BOOST

[riggerhunter]

Yes it will be just for fun. I just want to do something a little different and give me another project for the winter. I still have the question about the speed controls. I have a bunch of buddies and we just race together at the local campground pond. Can you give me advice on the speed controls, if the seaking's are any good? Or even the turnigy esc's without having to spend big bucks on castle. The set up I have now in the insanity rigger is with the UL1 motor and speed control, pretty happy with it and no issues runs very cool and the boat goes pretty good like I said I guess around the 50's for about 20- 25 laps before I have to bring her in and I still have about 7.5 volts left in both of the 5000ma packs(turnigy). The UL1 speed control is only 60amps but I figure I would have to go with the 120amp esc's with the leopard motors because they say in the specs it can draw 90amps. I was thinking about the leopard motors because they seem to be used by a lot of people and they seem to be happy with them (3674 2200kv) and they are not to bad of a price but I need to know if I can just hook them up on a y harness as mentioned above without any issues to the receiver. I don't know if the receiver will get to many amps from both BEC's going into one harness or not, I just don't know enough about it. Thanks for the help.

[6BOOST]

Yes you simply use a Y harness, Steve sells them in the store here on OSE. As far as speed controllers go, I really like the fightercat range, I think for what you are doing the bigger turnigy would be ok, it really depends what your budget it?

6BOOST

[NativePaul]

The ESC uses little or no power from the ESC, in fact if the ESC has BEC it is supplying power to the RX, which reminds me if your ESCs do have BEC you must disable the BEC on one of them by extracting the red contact from the RX plug on it.

I haven't used either the seaking or turnegy ESCs so cant advise on them.

That motor may be rated at 90A but it will be capable of pulling much more or less than that depending on the load applied to it even a little 28mm 400 size motor can easily pull 200A+ if overpropped (for a short time before it melts or the ESC burns).

As it will be faster with a single motor than a twin? Less weight, less cost, double the run time with the same amount of batteries

Not all of this is true by the way, singles do indeed often have weight and cost benefits over twins, but whether single or twins speed takes power, if you go faster with a single than the twin you will get less run time on the same amount of batteries, not double the run time on the same amount of batteries as suggested.

[6BOOST]

So say 6s2p 5000mah on a single 4082 will have less run time than 6s1p per 4082 in a twin arrangement? Meaning the single will pull over double the current/power of the engines in a twin arrangement? And if you meant more run time than if the single was on 1p, the boat would be 3+kg lighter, so any extra loading of driving a single imo would be offset by the savings in weight. I dunno, I'll tell you in a few weeks, I have both a genesis and a carbon 39" cat that will be getting a single and twin setup respectively=)