jacob711

hi i am thinking of getting this boat http://cgi.ebay.com/25-deep-vee-ARTR...742.m153.l1262
i might run it as is for a little while but when i get bored of it or when the esc goes bye bye i want to give it a new powerhouse, i want to get this thing going really fast, i dont really want to go out and buy the most expensive stuff thought, i was thinking of this stuff http://cgi.ebay.com/3650-brushless-m...713.m153.l1262
or this http://cgi.ebay.com/3656-brushless-m...713.m153.l1262
if they arent good enough to get me flying what motor and esc combo will, i was thinking of maybe feigao or nemesis blue, what size? and also how many amp esc. and do i need to run batteries with a higher or lower discharge rate than the motor/esc.

pompebled

Hi Jacob,

The boat seems nice enough for the money, my only concern is the non-watercooled outrunner when you use high mAh Lipo's, the runtime will get very long, which will most likely cause the motor to get very hot, as there's no airflow to cool it.
Adding a cooling armature similar to the one used for the ESC, mounted between the motormount and the motor will reduce the heatbuild-up a bit and maybe keep the motor in one piece. (like the one in this link http://www.rcgroups.com/forums/showthread.php?t=847559 , go to the site for close up pics)

As for your future replacement motor it's a tad on the light side for my taste, I'd prefer something like this:
https://www.unitedhobbies.com/UNITED...idProduct=4884
running on 4S (14,4V) (watercooled) should get you way over 65km/h.

The prop is nice to start with, you can always get a metal prop in future.

Go for it!

Regards, Jan.

RC_Bob

There's one big problem here. I don't see any trim tabs[X(].
If you get that boat you really should try and install some IF this boat is gonna go over 30 mph.

For a good combo I would use the SV27 system:
http://www.offshoreelectrics.com/pro...d=dh-blcomboaq
If you use it you really should use some trim tabs. Maybe even the SV27 trim tabs, lol.
http://www.offshoreelectrics.com/pro...tab1015&cat=52

I wouldn't recommend using that system that's already installed in that boat cuz an outrunner in a boat is gonna get pretty hot.

jacob711

okay thanks guys, yes i will be running trim tabs for sure the ones i will get are identical to the sv27, and i will also get turn fins, so Jan would that motor be able to get this this going uncontrollably fast and also is it water cooled, if not are nemesis blue water cooled, theres a guy in my gas boat club with a sv27 brushless pulling 60kmh and i want to blow him into the weeds, so id be looking at around 75+kmh, what speed control would be needed and when buying batteries do they need to have a higher or lower discharge rate than the esc/motor,

dicko

I'd run the boat without trim tabs & turn fins first to see how it handles. there are boats out there that don't need them, their hull design is good enough that if set up properly they handle fine without them. chances are you will need them on that hull though.

SV27dayton

The bottom looks alot like the SV. Nice looking boat for the money.

CadillacDTS2001

it is actually a seaducer bottom, with a ride pad.

jacob711

yeah i really love the look of it especially in the pic bellow, i have been looking around at motors and stuff and this is what i have come up with so far

not sure on the motor but probably a feigao or nemesis blue (both the same anyway) could someone please recommend one to get this uncontrollably fast i was hoping for about 80kmh/45mph or more (yeah i know im pushing it)

esc- http://www.offshoreelectrics.com/pro...od=xpo-blb100a

batteries- http://cgi.ebay.com/2-Propel-7-2V-45...742.m153.l1262
run in series for 14.4v

http://au.farnell.com/1341407/electr...SMANN-ACS-67P&
i have two of these chargers will they be adequate to charge 4500mah packs

Squidhead Racing

Jacob, by the sounds of it you have met Leon.

If you are after some good info, give Andrew Gilchrist a call at Fast Electrics in the East. I'm sure he'll be able to give you some excellent advice (and he's in Australia) http://www.fastelectrics.com/default.asp

It would also be a good idea to stop by the AMPBA forum, there are alot of Australian FE guys with some really neat set ups/ideas that I am sure would assist you in getting you to your goal http://www.ampba.asn.au/forum/index.php

Johno

pompebled

Hi Jacob,

It's not so much a matter of pushing it, but how fast the boat will run without getting out of control, 80km/h with a 25"hull is on the limit

The ESC will do fine.

The batteries are unknown to me, but most eBay batteries come factory made with thin connecting strips between the cells, in most cases they are too thin, and will get hot, creating a lot of resistance and heat, which power is not availale to the motor, often these strips simply glow up and burn under load.
If this is the case, the batteries need to get soldered in-line, or side to side using proper brass strips 1mm thick(at least) and 5-6 mm wide.

It's not a good idea to run two 6 cell pack in series and charge them separately, as the packs (specially the non-selected and matched ones from ebay) may drift apart during charging.
The life expectancy, with the speeds you have in mind, will be short.

I always charge my packs the way they are run, so 12 cell packs are being charged as 12 cells, not 2 x 6. (so a new charger is a future buy).

For what you have in mind, el cheapo cells are not the way to go, get a pushed and matched set.

Regards, Jan.

jacob711

thanks Johno, you should have seen the look on everyones face after seeing Leons sv27,

So if those batteries aren't up to it Jan how about the 14.8v 4800mah lipo at the top http://www.rclipos.com/Elite.htm but i was not sure if it could be placed up front (will it cause nosediving) otherwise two 7.2v wired in series for 14.4v, if wired in series will it still be 4800mah and the same discharge rate, also what type of Balancer tap do i need (the folowing are available Thunder power, poly quest, hyperion, align)

and this charger http://cgi.ebay.com/NEW-BOXED-IMAX-B...QQcmdZViewItem

could someone recomend what size fiegao motor that should be good for 80+kmh

alloutcustom

For that size boat, use a S or L size, dont use xl, too big. Try like a 7L. Or if you run a 4s lipo try a 9L but thatll be pushing that hull. 25" is pretty small. Shoudl be Okay tho. You should see 50mph from a 9L on 4s lipo.

pompebled

Hi Jacob, that charger looks good to me, you can charge about anything with it you may want to power your future boat with.

The 9L sounds good, keep the rpm at the prop around 25.000 - 30.000, more will just create more foam...

Keep in mind, setting up a boat usually takes me up to a full season before she runs the way I want it.
Getting a relative small hull to run as fast as you aim to, will take some tweaking.

Regards, Jan.

jacob711

thank again guys your a great help, i only just realized that deans ultra connectors are only good for up to 60 amps so what size OSE gold plated bullet connectors will i need, my only concern is that the terminals aren't covered like deans so if they touch my lipo will be dead

and also how can i use that charger at home because it is a 12v one

ryan_t888

I use only 5mm Bullet Plugs for all my connections. Females on the ESC, males on the motor. As for my battery, I remember red hot female (positive lead, female connector) or what ever is consistant in your club. Use 1/4" plastic Tubing over the male connectors when not in use.

You need a 12v power supply

Ryan

jacob711

thanks ryan, but with bullet connectors how do you stop them from touching each other when in use, do you have to wrap tape around them every run

ryan_t888

As I mentioned, use 1/4" plastic tubing over the male connector when your not using the packs. While running they will be fine. Just be sure to install them correctly using shrink wrap.

Ryan

pompebled

Hi Jacob,

The 5mm goldplated connectors are fine, but the 4mm bullit style will do just as well, in the power range you'll be operating.

The pic shows how I use them, the red one is usually + and the black one - , unless I do really stupid things with my batteries, the connectors will never touch each other and create a short.

The leads in the pic come from a set of 12 NiMH, used to power a 700 Neo motor, the cells and the motor got hot, the connectors never.

Regards, Jan.

alloutcustom

yea,a dn check out the Hobbycity gold connectors, im not sure how good they are, but they be good if you have a budget

jacob711

thanks again guys you are a great help, i am a total noob to FE's so i dont know much about them, i have just been writing out a list of things i need and i have a $800 total lol this thing was going to be a cheap little toy and now it is going to cost as much as my gas boat lol,

i just found this thing and now i want one instead lol http://cgi.ebay.com.au/BRAND-NEW-CAR...QQcmdZViewItem

in the videos it looks very fast, what kind of speed would it be doing, also what would the max runtime be with 2200 mah 3s lipo, could it handle 4s

i dont think that a 4s will fit in it but two 2s in series will but how do i go about charging them, can they be charged together and can they be balanced together, can the balance taps be modified to do them both at once

pompebled

My 'guestimate' would be 60-70 km/h, it's hard to judge from a video.

Keep in mind you need smooth(ish) water to run a hydroplane, it won't take nearly as much chop as the 25"monohull this thread started with, bring a resque boat, as you will flip it... Consider where you'll be running it, and get a boat to match.

On 11,1V you're talking 35000 rpm unloaded, in the video you can hear the 2600KV motor rev up quite nicely, on 4S the rpm's would be about twice as high as the boat in the clip.
I doubt if that would result in much more than a lot of foam and an uncontrolable boat in case the prop keeps it bite at 50.000rpm +.

I wouldn't even consider it, it's a really small boat.

Regards, Jan.

jacob711

im not sure if i will get it but i think i will

i plan on running it on 2x 2s 1500mah lipo in series, but i want to charge and balance them together, is there a way to somehow cut the balance taps ends off and get a 4s one and wire them up to it so they are joined together permanently or are there any adapters out there that the standard taps plug into that will convert it to a 4s tap, so ultimately what i am after here is a saddle pack, are there any saddle packs around that will suit my need?

CadillacDTS2001

use 5 MM.
Ryan can attest to this that 4MM's suck.
i ran 4MM's on my CC125 running a mega, the things were weak and basically same apart, they also lost all tension and become quite loose.
5.5 MM are the way to go

ryan_t888

That's too much of a hassle. I charge 2 2s packs by wiring them in series and run a balancer to only one pack per charge. In other words each pack gets balanced every other charge.

Ryan

jacob711

ok thanks, but is that safe to have unbalanced packs or 1 balanced and 1 not