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Author Topic: 30 inch brushless hydroplane project  (Read 11085 times)

gwa84the2nd

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Re: 30 inch brushless hydroplane project
« Reply #25 on: August 17, 2012, 07:36:01 PM »

lol  :-))
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #26 on: August 17, 2012, 08:00:04 PM »

you dont think its going to float then ?
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black magic racing

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Re: 30 inch brushless hydroplane project
« Reply #27 on: August 17, 2012, 08:29:09 PM »

you dont think its going to float then ?
LOL,,,i think it might be a body function you might have when you realise how fast your boat might go :embarrassed: :embarrassed: :embarrassed:
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #28 on: August 17, 2012, 09:39:35 PM »

i can only hope lol   {-)
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #29 on: August 17, 2012, 09:52:21 PM »

LOL,,,i think it might be a body function you might have when you realise how fast your boat might go :embarrassed: :embarrassed: :embarrassed:

do you think its going to be quick mate ?
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black magic racing

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Re: 30 inch brushless hydroplane project
« Reply #30 on: August 17, 2012, 10:07:51 PM »

do you think its going to be quick mate ?
i think with abit of testing and setting up it should be a quick boat,brushless is not my thing,im into petrol,but you mite find you wil have to shift some weight around as they like to have most of the weight up front ,the back of these should lift out at speed and ride on the prop,dont expect it to turn good without the turn fin as i mentioned befor,but for your first build it all looks good,only time will tell. :-))
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #31 on: August 18, 2012, 11:15:08 AM »

i had it in the bath last night to see how it sits in water and the rear is pretty low , was thinking of adding some lead weights to the front to conunter balance it , what do you think ?
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Mad_Mike

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Re: 30 inch brushless hydroplane project
« Reply #32 on: August 18, 2012, 12:09:43 PM »

no dont add extra weight. its better to reposition the parts. Adding weight at the front wont seesaw the rear out the water but will just push the front under so its just as low in the water as the rear.

Its usual for all of these surface peircing boats to have their stern right down in the water, they lift out when on a plane. For me personally i would have kept the set up as you originally had it. batteries at the front then motor.
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #33 on: August 18, 2012, 12:30:53 PM »

i couldnt because of the lengh of the prop shaft , but ive just made a battery tray the slides down the front of the boat past the motor and it seems like it will work good , as soon as its finished ill post a pic so you can see it ,

i think its better like this because the weights now at the front , and i have room to fit a waterproof box for the receiver which is always good

can you see any other issues i may have ?

cheers guys
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Mad_Mike

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Re: 30 inch brushless hydroplane project
« Reply #34 on: August 18, 2012, 12:57:48 PM »

you can cut down the prop shaft length you know :}
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #35 on: August 18, 2012, 01:18:47 PM »

i didnt know that but i think its a bit late to change it ,

this is what ive come up with it looks a mess but the battery is a tight fit and can not move when fitted inside the mount

once the glue drys ill stick the battery in and post another pic

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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #36 on: August 18, 2012, 04:44:00 PM »

this is it with the battery fitted in the mount

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Andyn

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Re: 30 inch brushless hydroplane project
« Reply #37 on: August 18, 2012, 04:53:41 PM »

Care to join me down the bottom of the lake? {-)

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Netleyned

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Re: 30 inch brushless hydroplane project
« Reply #38 on: August 18, 2012, 05:34:48 PM »


Could call it Bicycle Clipper  %% %%

Ned
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F1 madness

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Re: 30 inch brushless hydroplane project
« Reply #39 on: August 18, 2012, 05:57:07 PM »

that setup will see mid 30's mph thats if the hull can take the torque,you should of reinforced that area wouldnt surprise me if it pulls the screws the plastic off the torque of the motor
the other problem is the 4mm driveline wont last long with the torque of that motor if too large of prop used
3s on that motor ,thats a 4s/5s motor iv even run 6s on the leopard equivelent
Youll need a bigger esc too minimum 120amp unless you keep props small so dont expect too much from it  
JMO
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Andyn

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Re: 30 inch brushless hydroplane project
« Reply #40 on: August 18, 2012, 06:08:55 PM »

I think the bigger problem is with that battery where it is the first time the boat hits a wave it'll be 20,000 leagues under the lake {-)
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F1 madness

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Re: 30 inch brushless hydroplane project
« Reply #41 on: August 18, 2012, 06:30:30 PM »

Something else i just noticed aswell
Get rid of them deans connectors off the battery there only rated for max 50amp draw i wouldnt be surprised if your pulling double that on throttle up (obviously this comes down to prop choice etc) and more than that on continuous throttle
Youll need to use 4mm gold bullets minimum 
Iv seen what happens when the deans let go,a friend of mine used them lasted no more than 3mins POOF boat stopped in middle of lake when we got it back fried the esc,lipos and boat full of smoke lesson learnt
The deans had actually melted and welded the the negative and positive connectors together
 
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #42 on: August 18, 2012, 10:22:26 PM »

the motor is 3/4s and 85 amps , 900watts

as for the prop i bought a bronze one but i bought 4mm and the one i needed was 3/16 i think so thats just a plastic one off one of my other boats

im planning on getting this prop

 http://www.ebay.co.uk/itm/PROPELLER-X443-3-16-dog-drive-rc-model-boat-/150876886024?pt=UK_ToysGames_RadioControlled_JN&hash=item2320f69408

hopefully this is more like what i need im also going to get some 4s lipos

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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #43 on: August 18, 2012, 10:32:10 PM »

this is what it says on the website i bought the motor off

Brushless Watercooled Motor  3674 900W  2045 KV For 8.4 to 12 volts. 2S to 4S lipo or 7 to 16 Nicad or NIMH packs. Mounting hole spacing of 19mm or 25mm. Motor diameter 36mm, waterjacket 46mm diameter, length 74mm. shaft diameter 5mm. Max Amps 85.
 Replacement for 700 size motors but MUCH more powerful.   Use with 70 to 90 Amp speed controller

is the prop above im thinking of getting going to be ok or should i be looking at something different ?

cheers lads , i really am greatful for your advice
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F1 madness

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Re: 30 inch brushless hydroplane project
« Reply #44 on: August 18, 2012, 11:05:57 PM »

Dont pay too much attention to there amp ratings.you could 40-50% on top of that once loaded with a prop in the water,as for wattage you wont get no where near 900watts on 3s,to get that sort of watts you need to run them on the voltage limit
here was a post on rc groups some 1 got a data logger on 4074,2200kv leopard rated at 120amps,the data logger showed hitting the throttle the amps would spike over 200amps and was running a conservative prop octura M445
you still need to change them deans connectors on both lipos and esc you might be OK with prop though
I ran a 3674,2200KV on 4s with x442 prop in 25" deep vee hull  with no issues but your hull is much bigger in comparison 
Heres a vid but dont forget 1 thing when watching it,yours is a bigger hull on lower cells so wont be any near as quick
http://youtu.be/hRn-rHnsVGk
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #45 on: August 18, 2012, 11:12:04 PM »

i understand its a bigger boat and lower cells but if i can get it close to that on 4s and with a x442 prop ill be very very happen indeed , as for the hull i was mostly using this one as a practice as ive never done one i know you get get this hull in fibre glass so ill look at getting one of them in time

what connecters do you recomend mate?
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Stavros

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Re: 30 inch brushless hydroplane project
« Reply #46 on: August 18, 2012, 11:14:01 PM »

As his post states gold bullet 4mm Minimum...you can get them off Component shop


Dave
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #47 on: August 18, 2012, 11:17:57 PM »

nice one ..

its not the 442 prop i was looking at it was this one x443 http://www.ebay.co.uk/itm/PROPELLER-X443-3-16-4mm-bronze-dog-drive-rc-boat-prop-/150569631900?pt=UK_ToysGames_RadioControlled_JN&hash=item230ea6409c

its half the price of the x442
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F1 madness

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Re: 30 inch brushless hydroplane project
« Reply #48 on: August 18, 2012, 11:23:48 PM »

Which ever prop you get make sure its balanced and sharpend
I understand what your doing but dont wanna see you waste maoney then it goes all wrong and not bother again trying to pass on from what i learnt so you dont make the same mistakes thats all  :-))
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loveboat

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Re: 30 inch brushless hydroplane project
« Reply #49 on: August 18, 2012, 11:29:41 PM »

Which ever prop you get make sure its balanced and sharpend
I understand what your doing but dont wanna see you waste maoney then it goes all wrong and not bother again trying to pass on from what i learnt so you dont make the same mistakes thats all  :-))

i really am greatful mate honestly  :-))

im going to get a bit of ali or steel plate and reinforce that part of the hull were the motor mount bolts through tomorrow hopefully it will be stronger then

what do you think it will be capable of doing mph wise with that x443 prop and 4s lipos 45+ ???

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