Thanks once again, I would go for the hull with the motor and hardware installed. I calculated the total cost to around £230 excluding shipping fees from the boat supplier. Can you just quickly explain to me the difference between the Lipo of docile and speeding? Also can the charger be used for different batteries or only for one specific battery type?

Hi Jabbran,

If you click on the picture of the charger, you'll see a sticker that reads: NiMH/Nicad, three types of Lipo and Lead batteries, so yes, it'll charge about anything you'll need for the hobby and houshold...

One Lipo cell is 3,7V (4,2V fully charged) so 3S would be 11,1V and 4S would be 14,8V.

The motor supplied with the Arowana is a 1880 revolutions per Volt, so 3S would be 11,1 x 1880 = 20.868 rpm unloaded and 4S would be 27.824 rpm unloaded.
The difference in speed when using the same diameter prop is significant.

5S would be more than 34.000 rpm unloaded and make the boat ballistic (and a handfull to drive controlled)

Regards, Jan.

I see thanks. I'm wondering how do the batteries go in there to charge? All I see is a rectangular box, sorry for being such a newb. Also the products from that website, do they come in UK plug or no? How long does the speed battery last? Also how easy or difficult is it to put those parts in the boat, as I have no experience in this kind of stuff? Thanks.

I read about the 25" boat similiar to this from the same supplier and they have has some problems. I sure hope this does not happen to me because I would not be able to afford or fix such things.

Hi Jabbran,

The link shows one single Lipo cell: http://www.swanghobby.com/flyermate-...1-pr-1593.html
Look at the dimensions, it's a flat cell.
Stacking more cells on top of eachother makes for a 2S, 3S, 4S, 5S, 6S etc...

So it's not a box with cylindrical batteries stashed inside, it's a completly other technology and shape.

A lipo gets charged by the two main leads and has a balancer connector to allow the charger to keep every cell at exactly the same level.

There's no such thing as a 'UK' plug, other than the one that fits in the outlet on your wall.
If you buy a charger and power supply, the power supply will most likely have a connector to your AC outlet on the wall.

The ESC and Lipo come without connectors, you'll have to get either Deans or 4mm goldplated connectors and solder them on.
On my boats, I prefer 4mm goldplated bullet style connectors, but that's personal.

As I've mentioned before: There's no such thing as RTR, just factory assembled.
Making the boat ready for the water is something you'll have to do yourself, or have it done for you by an experienced boater.
I'm preparing a number of "RTR" as we speak for some novice boaters, who lack the experience, confidence or skills.
(gives me the chance to learn new boats without having to buy them myself...)

In my experience, the Chinese boats are decently made and run well with some attention prior to the first outing of the new owner, don't worry.
Should you hit a snag, there's alway the forum!

I forgot to mention you'll need eight (rechargeable) penlight for the transmitter, the one I ordered arrived today and naturally I had no penlights available.

The transmitter is decently made and doesn't look particulary cheap to me, main point is, will it function properly?

Regards, Jan.

I have the 25" ARTR from the Chinese distrbutor. It's an awesome boat, it rips!!! The fiberglass quality is very good, as is the hardware (all cnc'd/billet- no cast junk). One of the best handling hulls i've ever driven. Its amazing stable even in rough water. It literally blew away my buddies SV27 like the SV was a "toy" boat. This thing is a SV27/UL1 killer. I've converted mine to "big block" 36-56 motor, and a Castle Hydra 120. On 3s it will do low 40's. On 4s its pushing low to mid 50's with all the stock running hardware and prop (balanced/sharpened). I'll try to post some video of it/pics of my interior in the next day or so (I"ll start a new thread).

MKM [8D]

ORIGINAL: MKMotorsport

I have the 25" ARTR from the Chinese distrbutor. It's an awesome boat, it rips!!! The fiberglass quality is very good, as is the hardware (all cnc'd/billet- no cast junk). One of the best handling hulls i've ever driven. Its amazing stable even in rough water. It literally blew away my buddies SV27 like the SV was a "toy" boat. This thing is a SV27/UL1 killer. I've converted mine to "big block" 36-56 motor, and a Castle Hydra 120. On 3s it will do low 40's. On 4s its pushing low to mid 50's with all the stock running hardware and prop (balanced/sharpened). I'll try to post some video of it/pics of my interior in the next day or so (I"ll start a new thread).

MKM



Hi, you mean this one http://r2hobbies.com/proddetail.php?prod=rcbt1111 ? If I were to purchase that, what would I need to make it RTR, and can you recommend the exact parts, bearing in mind I'm from the UK. What sort of run time can I expect from it also? Thanks.

Hi Jabbran,

The boat in the link is out of stock and won't be back in their program, so I've been told.
That's why I gave the link to the Arowana hull...

If you want the 25"Prince, check this site, as I already mentioned on 6/19/2009:
http://cgi.ebay.co.uk/25-deep-vee-ARTR-with-motor-and-ESC-racing-spec-white_W0QQitemZ290323053764QQcmdZViewItemQQptZRadi o_Control_Vehicles?hash=item43989a3cc4&_trksid=p46 34.c0.m14.l1262&_trkparms=|301%3A1|293%3A1|294%3A3 0

If you want to know what you need to make the boat complete, take the list I made for you and cross off the items that come with the boat, the rest are the items you'll need to order extra, do change the 4S Lipo for a 3S to suit this smaller boat.

Regards, Jan.

Jabbran,

Mine is actually from the ebay distributor and came "reciever ready" with motor and ESC installed. Although the hull in the link you posted looks exactly the same. All I had to add was a radio system (transmitter/reciever and 1 servo for steering). Any 2channel radio system should work with this just fine, and any standard servo should work as well. The boat is small and light enough no special servo is needed. In fact i'm running mine with a Futaba S148 (the stock servo that comes with most Futaba radio sets). I think the tiny hull is defintly meant to run with li-pos, just because of the weight consideration. 3S would be ideal for the stock configuration as the motor is comes with 2880kv, is high on the
KV side. It will get hot on extended runs on 4s, on 3s its within its limits. 3s also helps keep the cost of batteries down. I bought this hull expecting "not much" but was very pleasntly surprised how well the hull handles.. it handles and drives like a "true" race boat- I would not hesitate at all to race this thing, and it would be very competitive with all the stock hardware. If you are going to push it hard read- extended runtime on 4s, or start getting silly with 5-6s, you will find the limits of the stock motor first (simply to high a KV to run on huge voltages), and the ESC second. The ESC that came with mine was an 85 amp unit capable of 7S!- I think that is much more than the specs on either of the Aqucraft boats....

MKM

Thanks again for your response pompebled, I was looking at that 25" deep vee because of it's price, the link you provided is very pricey unfortunately compared to the one from the website.

This is the exact link and distributor I purchased mine from. The seller is cool and will combine shipping on items if you request it... Boat arrived in perfect condition...

http://cgi.ebay.co.uk/25-deep-vee-AR...262&_trkparms=


he shows 10 in stock...


MKM

Thanks, so can you tell me exactly what I need to make this thing RTR and where to purchase it from? I'm looking at trying to maximise run time as much as possible so can you recommend what sort of batteries I need for this etc... thanks again.

Hi Jabbran,

You can take the radioset from my earlier list, the 3S lipo and the charger + powersupply, add 8 (rechargeable) penlights for the transmitter and you're good to go.

For longer runtimes, take the highest capacity 3S Lipo you can find, with at least 20C.

Or, mail the seller of the 25"boat webshop and ask if he can assemble a complete set for you; boat, ESC, motor, hardware, radio set, Lipo, charger, powersupply, rechargeable penlights, the whole shebang...

I'm sure he will oblige you.

Regards, Jan.

That's a good idea pompebled, with the batteries you suggested what sort of run time can I be looking at?

Hi Jabbran,
To the wishlist:

1) The larger the hull, the higher the speedpotential, how fast it goes depends on the motor and battery selected.
2) The larger the boat, the better the visability, modern radio's have more range than you can see the boat at...
3) There's no such thing as RTR, the boats are assembled at best, and usually not very good, you have to check every bolt and secure it with loctite, check for leaks and repair them, lubricate the shaft and check the overall set-up.
Best is to have an experienced boater prepare the boat for you to avoid nasty surprises such as a flipped boat sinking on it's maiden trip, because you were not told to tape the hatch shut prior to running the boat... (no, the clever rubber surround and the one touch button to close the hatch doesn't mean it's watertight, not by a longshot...)
4) see above.
5) more capacity (mAh) usually means more runtime, more runtime means more heat in all components, more heat requires a working watercooling on ESC and motor. Stock 'RTR"have 6-10 minutes runtime, depending on how you handle it.
6) Speed costs, size costs, battery capacity costs, so a commercial 'RTR'is a compromise.
7) Reliability is, next to good components, mostly a matter of maintenance and sensible handling


What's with your obsession with runtime?
If you want to run your boat longer, bring a second battery to the waterfront, or a third is you must.
Or have the charger with you and charge the drained battery on site, using a car battery as powersupply for the charger.

Please share your thoughts on the subject of runtime...

Regards, Jan.

It's not a obsession pompebled, it's just that I believe if I'm going to spend this kind of money I would like to have some fun with it for a while. Yesterday a friend of mine bought one of those cheap PX-16 electric boats and it lasted 10 minutes which flew by so quickly even with that boat.

Hi Jabbran,

Ten minutes is very decent for a Cat, which is lightweight (at least when on the plane).

I've been unning fast electrics for some years now, on NiMH, the average runtime was between 4 and 7 minutes, depending on the boatsize, number of cells, motor, set-up etc.
The races I run my boats in, typically are 6-7 minutes, depending on the class, so runtime is not a great issue for me, as long as I make the requirede runtime, I'm fine. With three heats per class on a race day, I have time to recharge my batteries before the next run.
Next to that; it's hard to keep focused for 6 minutes when you're wizzing around the markers with three to five other boats...

With the rise of brushless motors and Lipo's, the more efficient brushless motors made it possible to run longer on the same battery capacity, as Lipo's are getting more and more affordable, the higher capacity allows even for even longer runtimes.

The slower the boat, running Lipo's, the longer the runtime; you can run a small tug at scale speed for an entire day on a 5000 - 6000mAh battery, but as soon as you make it work hard, by towing things, the runtime can easily be cut in half (which would still be half a day...)
Going faster, means a higher amp drain on the battery; you can't expect a speedboat to run for more than 8-12 minutes on the same capacity going 50 mph+.

More speed means shorter runtimes.
And: speed costs.

Regards, Jan.