Need setup recommendations 42" aeromarine sprintcat & 51" x-hydro

[JIM MARCUM]

I would appreciate any tips on: choice of motor & kv; battery #S-total V-C; and props for each of these Aeromarine boats.

Current plan is: Leopard 5692 - 750Kv, Castle Hydra 200HV, three 4S 14.8V 45C lipos in series (12S@44.4V) double wires for both positive & negative poles w/solid 5mm gold connectors between ESC & battery, and Octura X462 prop for the 51" hydro.

THX, JIM

[Make-a-Wake]

What Hydro hull you got? Any pics?? The Castle 2028 is certainly an option...........

[JIM MARCUM]

Buth hulls are Aeromarine. The hydro is a X-hydro.

[Make-a-Wake]

Thats gonna be too much prop for 12s, and if you are planning only running 1p batts then it will be disappointing as well as getting the batts hot. I use 8mm gold connectors from ESC to the Parallel batt connectors.

[JIM MARCUM]

New plan is using three 14.8 batteries (3P) in series (44.4 volts) with 8 Gauge wires & bullet connectors & an anti-spark resistor on the batt lead wire.

What prop would you recommend for the 41" Aeromarine sprint cat, and the 50+" Aeromarine X-hydro?

JIM

[Rumdog]

That setup would be 12s 1p. Not 3p. To run 12s 2p, you will need 6x4s packs.

[JIM MARCUM]

Still learning the jargon. Thought "P" ment packs. I'm running 3, 4 cell 14.8 volt packs in series.
JIM

[Brushless55]

Still learning the jargon. Thought "P" ment packs. I'm running 3, 4 cell 14.8 volt packs in series.
JIM

P does = Packs
but in your setup you will have 12s1p
you only have a total of 12s single
12s2p would be 3 4s packs in series wired parallel with another set of 3 4s packs in series for 12s2p

[Make-a-Wake]

I was under the impression that P meant parallel...........12s2p = 12s(12 cells in series) 2p(two parallels of the series).

[Brushless55]

I was under the impression that P meant parallel...........12s2p = 12s(12 cells in series) 2p(two parallels of the series).

DOH!!
I think your right bro, sorry.. :blush:

[JIM MARCUM]

So much to learn, so little time.
THX, JIM

[D. Newland]

Hi Jim,

I'm not sure what part of California you're in, but if you run at Legg Lake or any other NAMBA insured site, 10S is the max you can run.

You can go 10S up to 12,000 mAh.

[Brushless55]

Good to know about the 10s limit
Thanks, I was thinking of building a 15s setup but now now..

[Rumdog]

Why is there a limit? Kind of ridiculous.

[D. Newland]

Because that's the max the rulebook allows and we want to keep our insurance intact.

You're free to do whatever you want on a non-NAMBA insured site.

Legg Lake is a NAMBA Insured Location.

Lastly, NAMBA insurance covers you (as an individual member) no matter where you run, but only if you are running within the NAMBA rules. If you run setups over 10S, your Homeowners/Renters Liability insurance will probably protect you.

If you have additional questions regarding this, PM me or start a new thread. I don't want to derail the OP.

[JIM MARCUM]

I'm still confused. If I run 3 14.8 volt batts in series for 44.4 volts & the batts will still get too hot, Do I need to run a 2nd 12S 44.4 volt set in parallel?? Geez, that would be a lot of weight. And will my Castle Hydra 200 HV handle the 24S total cells or does the ESC only "see" 12S when running the 2 packs of 44.4 volts each running in parallel? THX, JIM

[JIM MARCUM]

The lakes I run in are not NAMBA sites. I keep my favorites secret cuz if nitro or gassers show up they would kick all RC boats out cuz of the noise. Tree huggers love quiet. The only "pond" that allows Big RC boats around here is the Model Boat Basin in Mission bay & it's salt water.

[JIM MARCUM]

You're saying J. Mrkwitschka's NAMBA T Hydro record of 140.36 MPH was done with only 10 cells? What the hell was the actual motor/ESC/battery used? JIM

[Brushless55]

I'm still confused. If I run 3 14.8 volt batts in series for 44.4 volts & the batts will still get too hot, Do I need to run a 2nd 12S 44.4 volt set in parallel?? Geez, that would be a lot of weight. And will my Castle Hydra 200 HV handle the 24S total cells or does the ESC only "see" 12S when running the 2 packs of 44.4 volts each running in parallel? THX, JIM

the reason for running 2p or even 3p is having the amps to back up this system :thumbup1:

[Make-a-Wake]

I'm still confused. If I run 3 14.8 volt batts in series for 44.4 volts & the batts will still get too hot, Do I need to run a 2nd 12S 44.4 volt set in parallel?? Geez, that would be a lot of weight. And will my Castle Hydra 200 HV handle the 24S total cells or does the ESC only "see" 12S when running the 2 packs of 44.4 volts each running in parallel? THX, JIM

As Brushless pointed out, the 2p or second set of batts is to provide the extra amperage the motor wants. The ESC will only detect 12s since that is all it is actually getting................its just getting alot of mah/runtime. As an example, my 50" Hydro is 9s2p. The batts I use are 3s 5000 40c...........six of them. Three sets of three in series, then paralleled to another set of three. In 1p form the batts will only provide 200 continuous amps, in 2p form 400. The motor is pulling close to 200, so the batts would really be struggling to keep up, which in turn gets them hot, strained, and possibly puffed. The top speed would also suffer quite a bit. Yes there is a bit more weight involved, but the extra amperage more than makes up for it.......keeps mine planted better. Mine weighs in at 24lbs BTW.

[Fluid]

You're saying J. Mrkwitschka's NAMBA T Hydro record of 140.36 MPH was done with only 10 cells? What the hell was the actual motor/ESC/battery used? JIM
No, he set that record with 32 x 1.2 volt nickel cells powering a big Schulze ESC and Lehner motor. That would be equivalent to about 8S power today. Going fast isn't all about horsepower.


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[JIM MARCUM]

I'm begining to realize that. Thanks for the details. JIM

[JIM MARCUM]

MAKE-A-WAKE: That's what I needed to know. So how fast is your 50" hydro & which prop do you use? JIM

[Make-a-Wake]

MAKE-A-WAKE: That's what I needed to know. So how fast is your 50" hydro & which prop do you use? JIM

Got her to 58.9 on the Gps. Running a cut down prather s270, it's now 63mm in diameter............1/4" drive all the way thru.

aSP2wLB7rFM

[Fluid]

Why is there a limit? Kind of ridiculous.
Why on earth would you say that? Most racing organizations - full scale cars, planes and boats included - have some kind of engine power limits. In model boat racing was decided that 1.83 cid, 53 cc and 42 volts are enough, and they are for any reasonable racing use. There are safety concerns which need to be addressed to maintain insurance. Otherwise there would be no organized racing. It makes perfect sense.



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[Fluid]

For another point of reference, my 20 lb 41" Stryker catamaran hits 65 mph in race water running 10S2P/9000 mAh to a Lehner 3060/785 motor spinning an x465 prop. It pulls between 140 and 150 amps average during a race heat and can pass almost any gas cat on the course. I would expect a 50" hydro with similar power should do at least as well when set up right.



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