llDemonll

what did that part of the post mean? the higher c (whatever that is) rating i understood as kind of the 'speed at which the battery could put out its power'

also does anyone know of a boat that is close to this one? jet drive included or not, mainly the hull i am concerned about. as of now im going to be paying around $100 for one of these shipped from australia (58 + 40 for shipping)

sundogz

Yes, the 'c' rating is how fast a battery can put out power. You multiply that by the ma output to get the amps the battery can supply the motor at any one time.

llDemonll

So I've managed to score a jet boat (or a place i can get them from, seeing who of my friends are getting them first for shipping purposes).

I think i've decided on:

Motor: http://cgi.ebay.com/WALKERA-180L-320...d=p3286.c0.m14
ESC: http://www.ecpower.com.hk/index.php?...roducts_id=194
Battery: http://www.ecpower.com.hk/index.php?...roducts_id=215

We would all be going the same route as far as parts so the boats are similar. Anyone have suggestions on these? or would they make for a good setup.

And with the battery, how would waterproofing it work? just tape the hatch on the boat? or is there a way we can make them "waterproof"? (not run underwater, but i dont want to have to worry about getting a bit of natural water inside the hull

sundogz

One of the last suppliers of this boat - in Austrailia. [link]http://www.stanbridges.com.au/shop.NQD6024[/link]

Get 'em while you can!

WakeBoardnBash

Sure is alot of KV for a 3s set up.

llDemonll

i was deciding on that based on what others were running. i saw a few 2000kv but mostly 3200 and a few 3500

dont know how much speed difference ~3200 and ~2500 would be, any ideas? (as far as actual boat speed)

sundogz

3200KV is a good speed with a 3s battery (11.1 x 3200 x 80% efficiency guesstimate) = 28k rpm. That is fast in this jet boat. Sdg

llDemonll

the 35a seaking esc with a 20c 3S lipo wont burn out the 2040 size walkera motor i linked above will it? i was looking at others (and i know it depends on prop size and such too) from www.unitedhobbies (they have max amps listed under some inrunner motors) it says the max load should be about 13A (from what im gathering).

sorry so many questions, trying to do this on a limited budget so i dont want to buy wrong parts and have to buy more after that (or buy ones that wont last).

TwinJetMax

Hey mate.

Think of it this way, Volts are based on supply, and and amps are bases on demand.

If your battery is too highly voltaged for motor, it will burn it out. but if your motor is two highly voltaged (rating) for the battery nothing will go wrong.

The amps are opposite. A highly rated ESC and battery will not harm your motor, but a motor that pulls too many amps for the battery and esc will blow them.

llDemonll

so (and this is more for my own use and for someone to confirm)

the motor im looking at has a 6-18v operating voltage, the battery im looking at (3S) are 11.1v so that is a green light

the esc im looking at is 35 amps, the batteries im looking at need to be at least 35A ((mah * c rating) / 1000) so if i get a 2200mah 20c battery thats 44amps (which are the batteries i have been looking at), which is higher amps than the esc will pull, so that is a green light as well.



so if i am hopefully right on both those then i think i finally have a pretty good grasp of the basic concepts behind all this selection stuff. RTR is so nice sometimes haha

if my logic above was right, then could i feasibly buy a 4000mah 10c lipo? (4000 * 10) / 1000 = 40A? and if so, would you recommend that if i get larger packs (say 4000mah) i keep the higher C rating (20 or so) or go for the lower C rating (10 or so). as i understand it now it would be best to stick with a higher C rating as it would give the pack a higher mah/hour discharge rate, in theory making it last longer that the same mah pack that has a lower c rating?

TwinJetMax

Yes for the first two.

As for the third, the C rating depends on the quality of the cells, but the MaH rating is much more dependent on the size of the cells. A 4000 MaH battery will weight a lot for a little boat. Large capacity batteries are also expensive, so you are better off most of the time buying two smaller high C rating batteries.

llDemonll

awesome, i finally understand most of it. thanks much for laying it out in terms that i had to figure out still =D

and yea, im thinking somewhere around 2500mah 3s 20c packs are what i'm going to end up getting. i know people have had good luck with turnigy motors, unitedhobby.com has turnigy and other "semi-name-brand" lipo's that im thinking of getting to start off with.

any recommendations on a well-priced charger? that's something im willing to invest a bit more in

thanks again for the help =)

TwinJetMax

I use the turnigy accucell 6 and have had no problems with it. It works really well.

Yep I'd say that that sort of battery is about right.

sundogz

Thanks Twinjet for clearing that up. Sometimes I'm not very good at 'splaining things. Demon, sounds like you now have a plan - have you found a boat yet? I'm wanting to get another Tear Into for a friend, but shipping cost is prohibitive from Australia, and they seem to have disappeared from the rest of the earth (copyright infringement?). The Graupner Jet Sprints (what is left in stock) are quite pricey.

llDemonll

ah bummer, i was going to ask if anyone else wanted a boat before i ordered them because i ordered 3 last week but i wanted to get the order in before i left for the weekend to make sure i had my boat before going back to school

http://translate.google.com/translat...3Dp3286.c0.m14

he also has a website sedent.de. if you ask around im sure you can find more people who want them, i paid 260 for 3 boats shipped to usa from germany ($85 each). he charges 35 to usa to ship however many you want (i imagine if you order 5+ shippping may be more or soemthing just because of package size) but hes pretty good with communication too. i ordered mine 4 days ago, they were shipping out 2 days ago so ill let you know when they reach me in washington.

check ebay.de and ebay.co.uk a bit, there was one for 26 EUR on europe ebay but i didnt talk to the guy about shipping because he only had one

edit: i called zhobby.com about http://www.zhobby.com/17wajetrcelr.html and http://www.zhobby.com/17wajetrcelr1.html and the customer service people (called twice on two different days) said they should be getting more in stock near the end of this month so you may wanna check around there a bunch. they are coupled with another website or two that looks the same and based out of cali so shipping shouldnt be terrible, dont know how much though

sundogz

I'll be sure to remember Z Hobby later. Checked out ebay.uk to no avail. These are getting tough to find for sure. Thx, Sdg.

sundogz

and my reply...

Hi mray, I'm glad to hear that you will be making these boats available (though not too thrilled at the price) as they are as scarce as hens teeth here in the good ol' U.S. But your ad implies that you can put the supplied BL motor and esc in it and have a RTR boat, which ain't so. You would also need to acquire a proportional 2 channel transmitter and receiver - because the electronics that come with the NQD are a proprietary (cheaply made) non-proportional system, and not compatible with the speed control or the brushless motors you supply. And you would need a (steering) servo for the same reasons.

You might consider changing your ad to prevent confusion. And consider that after spending the $189 for the boat, motor and esc (and ‘acquiring’ another radio system and steering servo) one would have quite a lot of $ invested in a (hacked) toy that only runs for a short time on the stock nicad battery - without investing more $ in a (comparatively pricey) lipo (or similar) battery and charger, etc.

I see that you joined RCU in '04 and have had limited participation in the forums. There is a wealth of information in the �All things Jet Drive� section about that knockoff boat (and some limited info in the "Tear Into" forum as well) that will help you in your future conversion. Feel free to ask questions, there are plenty of experienced enthusiasts more than willing to assist. Sdg

mray

Hi thanks for the reply via pm and here on the thread. Let me clarify a few things...


No that is an incorrect statement. What the ad should convey is that we are supplying a brushless motor and ESC with the basic kit. It does say this will have to be installed by the owner ( I have also edited this ad). But since you are bringing this up, let me just say that I am not interested in offering a turn key REVISED version of this boat with all the mods installed, including a new two channel radio. I am not interested in doing it for two reasons, the first is based on your statement about cost. Second is, for me to do that work, the customer would have to pay for the time for me to do it and I am not interested in getting into that. What I am interested in is attempting to help with is a single place to get most-if not all the items and boat for an individual to do their own mods. I realize some of the key pieces to make the transition from the stock config to a well performing brushless unit are missing from our ad. Some of these items may be added later-however lipo's and two channel radios are really easy to get.


I am aware of that. Though because of cost, I decided not to include these as most can find a good two channel unit of their own elsewhere or they may already have enough extra radio accessories to do it themselves. Though, I can certainly throw a unit together and bundle it.
Again, I think you might be missing my point here which certainly means that our product Ad isn't doing it's job. Most people are already doing this as indicated here on the forum and spending a fair amount to mod these boats. Folks can purchase their own LiPo's where they want-some like certain brands, it appears to be a moving target on which size of Lipo to go with, so to make it easier, I will leave this up to the individual-at least for now.

Thanks.

llDemonll

no offense, but $190 for that boat? you've got to be joking. motor = $30 max otherwise it's far too big for the boat (which with a 3.13mm shaft, yours is), that seaking esc is $40.

You trying to scalp these boat's is something that i personally frown upon.

that, and you won't even build the boat for the customers that you do manage to get.

mray

This is a well intentioned opportunity and is not a scalp. My cost on the parts is much higher than your average hobby shop. YOU do have the choice to buy just the boat itself and the other parts from another shop. The only reason I decided to offer it is because I wanted a few of them, had the opportunity to get them, and to do it, I have to purchase a minimum quantity. If you are interested, great, if not, that's fine too.

sundogz

mray, the shaft size on the Tear Into is 2.3mm, so you might offer motors that will use the original coupling, or offer a coupling that will adapt to the motors you offer. Or better yet, don't supply motors/esc's - let the customers handle that. And most importantly, build one of your own first, so you know what you're getting yourself (and potential customers) into.

Thank you, but I'm not interested at that price. [X(] Sdg

jetsprintbasher976

My Feedback: (-1)

hey just found the new thread good idea                 i just found a jet sprint  on ebay moments ago heres the item #310151002137    4 $70

+ ship
but if some one is ordering these and can hook me up for one less than ebay's . i'm in  PA  let me know i would very much appreciate it.  i have a jet boat cracker box whoops begineers mistake but i make it work will have pics and possible vid soon

llDemonll

He is the eBay user I ordered from but on ebay.de

2-2.5 week shipping to WA from germany, not too bad and he ships for $35 flat fee which is pretty good IMO

I actually haven't seen my boats yet, they are at home and im out of town at school, but i'm assuming they're just the boat like normal in a box. decent price for how hard it is gettign to find these. see if you can pair up with some people, $70 per boat + 35 eur flat shipping cost, 3 boats is $85 each, less is more, and more is less.

sundogz

What a find! But I don't understand the ebay ad - looks like good ol' American ebay, but the catagory is in German:

Listed in category: Spielzeug > Elektrisches Spielzeug > Ferngesteuertes > Boote

Weird, maybe someone can explain that. Glad to see them for sale on ebay again, and have to wonder how long they'll be available.

jetsprintbasher976

My Feedback: (-1)

i asked that German dude what kind of deal he would give me on ten boats and he told me that he doesn't ship to us