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[bikerdude999]

But you can never have too many boats!

Have to admit I've seen a nice 5cylinder radial engine, but no use for it, my idea of an ic boat would be a nice bike air cooled v-twin lol

[bikerdude999]

Well it's been a couple of weeks since I've really done anything, mainly due to me being a bit lazy....


Anyway, I've just finished making 4 of the large white hulls for someone, and have made up a plug and mould for a new hull aswell, similar in size and style but more 'modern'. Spending most of my planning on what I'm going to do with various versions using these hulls while I wait for the parts from HobbyKing. In addition to the plans in the above posts, I'm now also planning on doing a clear gelcoat on 1 of the smaller hulls, letting you see the glass matting of the hull, and also making it transparent, and then I'm going to fit different coloured lights inside, which should look quite good on the lake during the dull winter days at the lake....


Anyway here's a couple of pics of the mould, finished hulls and a hull in the mould.

[red181]

Hi, thought you might like to see this, I have experimented with quite a few brushless, and I think you can make your hull go real quick
 
http://www.youtube.com/watch?v=yZPG8XKjTk0
 
I know its a different hull, this is all ply, but the purpose is to show the speed of very cheap brushless setups. The motor is from hobbyking, I had it lying around from a plane, its got a 35mm "x" prop and is running on 3 cell lipo.
 
The motor was £15, battery £15, esc was a cheap chinese forward only £15
 
Just a few points, when you do the next hull, get the shaft angle to be as little as possible, the tip of the prop blade needs to be much closer to the hull, this will minimise the nose coming up, you dont want to be strapping extra weight in  if you can help it, that will slow the boat down, at the moment you shaft angle is contributing to the nose up attitude, as the prop is pushing up, rather than forward
800mah is way too low, get a 2200 as a minimum, currently on sale at hobbyking I think for a tenner, I see you had a copy of bmfa magazine in one of the shots, so assume the 800mah is off a plane or heli?
 
that brushless motor was about 1500kv, I know the racing guys use a much higher kv, runtime was about 15 mins before my low voltage alarm was going off, long run times generally mean slower speeds, its a play off! Paul

[bikerdude999]

Thanks I've just received a new motor, ESC and batteries for the boat, the 800Mah was from an apache helicopter, though that magazine is actually my GF's dads. The angle of the shaft was dictated by the length of shaft I had here, but when I get some money I'll buy a longer shaft, make up another hull and have another go, or I might just go for a water jet drive, I can't decide...




My GF's Dad made up another of the large hulls last week, as he wanted to have a play around with masking off the mould and using different coloured gelcoats, the result is not perfect, but certainly not bad, but if I paint over it in a similar/matching colour, when it gets scratched it won't notice so much! Here's a few pics of the hull and the few places where the different colours have gone where they shouldn't have (though I'm sure practice will make perfect)














And a member of the club I'm in has kindly donated me a prop shaft and motor (the motor is a 12v fan motor from a car), I have the choice of 2 motors, whichever I choose not to use, give back to him.

[bikerdude999]

Well, I can never have too many projects, so over the last few weeks I've been making a new hull, with a huge amount of help from my future father-in-law. We've made 1 hull at work, but now need to make a new mould, as the initial mould and hull was done using a vacuum system to make the hull, but I want to just do it the conventional way. (the vacuum method seems to give a better mould, cleaner/smoother inside the hull but not so easy to do a bit at a time in my garage.


Anyway I have no exact measurements at the moment, but its approximately the same size as the red/white/blue 1 above. Here's a few pics...

[bikerdude999]

Finally got round to fitting a motor etc into the blue and red hull. No deck has been fitted yet as I just wanted to see it went like. Decided I'd try out brushless for this hull, and a couple of weeks ago took it to the lake with a small brushless motor fitted, and a selection of different sized/number of bladed props, and some 7.2V NIMH packs. Fitting anything bigger than a 35mm 2 blade prop ran ok out of water, but made the motor stall as soon as it touched the water. Performance on the 35mm with NIMH was ok, but accounting for the added weight of deck/superstructure when it's finished, it would've been underpowered. So when I got home I dug out a bigger brushless motor, and fitted that, still using the same 2 blade 35mm prop. As I was getting everything ready to go to the lake last Sunday, I made a last minute decision to just bite the bullet, cut the connectors off the 11.1V Lipo's I bought, and use block connectors to link them to the ESC. Performance has been drastically increased, with good top speed, lifting up out the water nicely, and good high speed maneuverability. Hopefully attached is a video, this is after running the boat at near full throttle for around 40 mins, with no signs of any loss of power.


The set-up in the boat is messy as the brushless esc doesn't supply power to the RX, and I've not got an RX battery pack to use, so I had to wire in a brushed ESC, with a separate 7.2V stick pack to power the RX.


Happy to answer any questions...



http://youtu.be/ub9dNl2CXSs