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[ImplodedHamster]

Hello (again) people :)

I tried posting this is the Newbie section, but got no reply, not even a hello :( so thought I would try posting it here to see if more people read this section?

My name is Robert, I mainly fly model aircraft (Planes and Helis) but have recently been given a boat hull which I would like to get going.
I have a good understanding of building planes and such, but never boats. Currently studying Mechanic and Electonic engineering at Bath Uni.

The hull in question is about 3 to 4 foot long and looks like this:

More photos here: http://s1236.beta.photobucket.com/user/ImplodedHamster/media/null-8.jpg.html?sort=3&o=0

I can't find any plans for it, so if anyone know what it could be that would be great.
Also, what kind of power set am i looking at? Is it possible to do this with 3s LiPos as I have loads lying around from flying.

Thanks
Robert

[Stormbringer]

could have sworn i welcomed you but anyway
welcome aboard 

[aLEX vk2kr]

Hi Robert

I am in a similar situation to you with a dinghy hull, initially thought of steam power
but the cost is prohibitive and settled on a 700 size brushed motor of low Kv and
2S lipo for power.

I also have a large stash of outrunners from planes, and would for what it is worth
suggest a low Kv 36mm diam outrunner for your 3S packs.

Hardest part will be selecting an appropriate prop and maybe the expert here can help
once you have decided on the which motor you will use. I am assuming that the
model will not be planing? otherwise a higher Kv and smaller prop would be appropriate.

You might have to select a water cooled ESC depending on power requirements.

BTW - welcome to the group - a very nice bunch of fellas here

regards

Alex - in Oz

Hello (again) people :)

I tried posting this is the Newbie section, but got no reply, not even a hello :( so thought I would try posting it here to see if more people read this section?

My name is Robert, I mainly fly model aircraft (Planes and Helis) but have recently been given a boat hull which I would like to get going.
I have a good understanding of building planes and such, but never boats. Currently studying Mechanic and Electonic engineering at Bath Uni.

The hull in question is about 3 to 4 foot long and looks like this:

More photos here: http://s1236.beta.photobucket.com/user/ImplodedHamster/media/null-8.jpg.html?sort=3&o=0

I can't find any plans for it, so if anyone know what it could be that would be great.
Also, what kind of power set am i looking at? Is it possible to do this with 3s LiPos as I have loads lying around from flying.

Thanks
Robert

[Corposant]

From your picture, it looks as if it could be the startings of an entirely scratch built model. The Photobucket link doesn't work for me.

The boat is definitely not within my field of experience but your other pictures might evoke some help from the pool of expertise on the forum.

Mike

[malcolmfrary]

Could be a lakes launch.  A picture of the underside of the stern would help at guessing what kind of prop arrangements could be made.

[ImplodedHamster]

Thanks for the welcome :)
Alex, what kind of run time do the boats get? I'm guessing much longer than planes? would a 2.2Ah 3s be enough? or will i need to use multiple batteries in parrallel
Malcolm: does this help?

btw, I forgot to mention the hull appears to be fibreglass

[malcolmfrary]

With the right motor it should cruise nicely, maybe an hour or so off 2.2AH with a 15 volt 545.  Depending on the actual size, a bigger motor might be wanted, but it looks a gentleman's cruiser rather than a racer.
I asked about the stern because some home designs have a stern that just cannot work with a prop and rudder - this looks OK, it was just hard to see from above.

[unbuiltnautilus]

Is it just me, or does it look like a racing yacht hull with bulwarks added on top?

[malcolmfrary]

Is it just me, or does it look like a racing yacht hull with bulwarks added on top?

Its just you.  Yachts, especially racing ones, rarely have a skeg for a prop tube.

[unbuiltnautilus]

You know you can stick them on afterwards?

It just has the appearance of a 1 metre yacht or similar, I am certainly an advocate of using unusual hulls for different purposes, and would love to see some sort of classic scale top on the hull. I just wonder what its length is, and if you stuck a mast on it, would the local yacht club let you enter?!
Knowing the local yacht club, possibly not

[aLEX vk2kr]

Hi Robert

Don't have a clue on run time as it would depend on motor/prop combination
and the resulting current draw. There has been nothing that I can find that would
be the boating equivalent to 'electricalc' to be able to even guess.

I would suggest that you just try your existing battery stocks and see how they go,
if needed you could always parallel your 3S packs for extra time.

My hull is more deeper V, and needs lots of ballast, so picked up a cheap
2S 8000mah pack from "HK" that should provide lots of run time. I think
that I will still have to place a kg or 2 more lead ballast to get a reasonable waterline.

Your hull is much more flat and should be OK with the smaller pack.

One thing I have learnt - you need a few different props to try out to
get a reasonable compromise on speed/duration.

You have a lovely hull and look forward to seeing it finished and running.

Now back to repairing a F5J electric glider for the next comp,

regards

Alex

Thanks for the welcome :)
Alex, what kind of run time do the boats get? I'm guessing much longer than planes? would a 2.2Ah 3s be enough? or will i need to use multiple batteries in parrallel

[malcolmfrary]

You know you can stick them on afterwards?

You can indeed, but this one looks like the skeg was part of the original moulding.  Mind, adding some internal bracing to support a fin and some masts could result in a nice yawl, but probably a lot more work than fitting motorising bits. 
Another thought for the hull, and fitting a superstructure over the deck openings was a drifter, but the stern looks a bit too squared off for that.