What Motor?
 

I have a Tower Hobbies turbo vee 2 and i was wondering what motor would be best to make it go faster? I'm looking at a graupner 600 motor, would that be good?

RE: What Motor?
 

Yes that motor would push that boat fine, but are you going to change the ESC? I would think you need to.

RE: What Motor?
 

yeah, im planning on it...

RE: What Motor?
 

Is your budget large enough for a brushless motor/esc?

Ryan

RE: What Motor?
 

no it isnt

RE: What Motor?
 

hi Master,

i'm a first-time builder facing a similar dilemma, just built myself a deep-vee hull and i have no idea what setup i should be running on it. it's made of sheet plastic, reinforced with GRP on the inside, is 86cm long and 17cm wide. First of all - will this thing go round bends without washing out? i've been comparing it to some hulls on the market, and a ratio of 1:5 (beam:length) seems to be closer to that of a sailing boat with a nice sturdy keel rather than a power boat. Doesn't weigh much - my estimates are about 400g, but need a good set of scales to verify. I basically need to kit it out with everything.....a good option i was considering was to cannibalise an RTR Graupner Giant Racer (with 3 600 motors) but would that be a bit overkill? i want it to fly..... with some imagination i might turn it into a canard (with sponsons on the side). Check out the pic and tell me what you think - took it with my phone so sorry for the quality,

Andrew

RE: What Motor?
 

hi how did you make that hull and how did you reinforce it?

RE: What Motor?
 

hi Speed,
i bought a couple of sheets of 3mm plastic, designed the plans myself, cut, taped, and glued everything together. i used 5 minute epoxy all along, but this needs to be reinforced from the inside with fibre-glass-cloth and some good-quality resin. i advise you to first do the seams and then cover the whole thing with two thin layers, possibly reinforcing the transom with a third layer. You might notice that the top of the boat actually came from an RC F1 car which i had won at a fun-fair...i removed the driver and blocked the hole with a piece of plastic bottle (you know the Mr. Clean spray type ones you use for the kitchen?) I made rails from strips of balsa wood which i glued and pinned into place, removing the pins once the glue set. I plan to spray the whole thing matt black, and stick on white decals of "The Punisher", with skull and all.....you think it will keep steady on corners though?

A

RE: What Motor?
 

I would go with a duel 700 series setup or single 700 motor. Either way should be good.

Ryan

RE: What Motor?
 

I bought Graupner Speed 700 Turbo S, hope to be overvolting it to 12v (it's a 9.6), and i think i'm gonna chop off a good 10cm off the back of the boat...i tried it in the bath, and it's got more than enough flotation to handle the weight. Btw - i weighed it.....far from the 400g i was telling you about, it weighs a brick-like 1kg. With cells and all i think it should weigh in at about 2kg...is that too much for a 70cm boat?

A

RE: What Motor?
 

I run 16 cells on a rated 9.6volt 700 series motor. (19.2Volt) Water cooling the brushes/case is most definetely needed in that case and temps of motor-esc-battery's should be checked periodically for the first few runs.

I would not chop 10cm of the back of your boat. The 700 motor should handle the weight and size. Just make sure your prop it appropriately.

Ryan

RE: What Motor?
 

Hi Ryan,

thanks for the advice...bought myself a solid 700 Turbo S (9.6v) from graupner. For the moment i think i'll be running it on 12v, then keep adding more cells to see what happens. on the other hand i did chop of a good chunk...(about 15cm) cos i made an aluminium rudder and shaft holder combo which made the thing look too long....will take some pics this evening....
Like this it looks more like a boat and less like an F-16 with the wings chopped off. How big is your boat with the 700 motor and the monster battery-pack? must weigh a ton aye? can you post some pics?

Regards,
Andrew

RE: What Motor?
 

Last summer I flipped it and blew out the receiver and ESC. I recently just pulled out the hull and it is totalled. It was a custom built cat hull out of insulation foam, this made it extremely light. Since it will dent with any type of impact it is extremely important to drive and transport it carefully. This problem is something I am willing to sacrafice for an extremely light weight hull.

It was 610mm(24" ) long by 229mm(9" ) wide. I would not want to go any smaller.

I am currently trying to rebuild/modify the plans I have made a while ago. So far I have a 3D model viewable in SolidWorks 2004. I saved the file in JPEG form so it may be viewed. There are a few changes I want to make to it yet. The setup inside from the back to front is going to be steering servo, 2 6-cell batts, motor, radio gear. Before hand I had the steering servo, motor, then batts.(rear to front) I could not get the CofG far enough back.

Ryan

RE: What Motor?
 

Cool idea Ryan,
i've tried building boats from HDF before - just to make a mould....and yes you can cut it like butter and its super light. You might want to reinforce it a tiny bit though...how about the super-thin modelling glassfibre cloth? it's about.01 of a mm, so i doubt it would make such a big difference in weight. remember to insulate the motor and batteries well....you don't want them melting holes in the foam...GRP is good for this too, or perhaps balsa would be even better.

RE: What Motor?
 

here are the pics i promised...

RE: What Motor?
 

I've ran it before without reinforcing the foam or insulating it from heat on 16 cells! I had no problems at all. The only problem I may encounter is deformation from some kind of impact. This is the risk I'm willing to take. For $12CDN, I can make 6-8 boats out of 1 sheet of foam. Its the pink inulation foam used in homes. It is extremely strong for foam, as it is very dense.

Your hull looks quite a bit different. What is your final plans for the setup? Brand --> Servos-Batteries

Ryan

RE: What Motor?
 

yeah - i've used similar foam....baby blue though not pink;) it's extremely strong and light...and i think i'll give it a try too...when this project's done....
I bought everything from graupner - got a good pistol-grip RC for 105€ - forgot the name exactly but it's got a small screen on the side which tells you how much charge you have left in your batteries....it's a three way thing...the servos are graupner standard, as for batteries guess what....graupner too! 12V 3600mAh. ESC is the V35 from (yeah you guessed it) graupner. i'd have bought other brands, but i'm new to the scene and shops here seem to stock graupner only here - perhaps a little bit of robbe stuff, but anyways will give it a try. bought a 42mm carbon prop, and a 4mm flexishaft that fits into a reducer coupling (the motor has a 5mm shaft) hope it works considering i've spent considerable time, energy and cash on this thing....gave it a layer of undercoat yesterday. got any pics of your boats ryan?

RE: What Motor?
 

I am currently designing an updated version of the old model posted. The only pic I have is the one in my gallery of my tunnel.

Ryan

RE: What Motor?
 

so here it is finally...am in the process of fitting in the motor...hope the outdrive isn't sitting too low in the water....we'll see
a

RE: What Motor?
 

It looks way too low. What type of drive are you going for? You currently have a submerged type setup.


Ryan

RE: What Motor?
 

Which is faster? i'll be running a 700 turbo on 10 cells with a 42mm prop - boat is about 70cm with drive and all

RE: What Motor?
 

Surface Piercing is the most effiecient

Align prop center with the bottom of the "V." Half of the prop will be out of the water and half will be in, while on plane. You may be able to get away with a 45mm or bigger prop as well.

Ryan

RE: What Motor?
 

You're the best....!!!! thanks a million as this should be much easier than drilling the bottom of the hull! will let you know tomorrow how it went. i was just concerned by what other members said about 'cavitating' what does this mean? isn't it better if all the prop is pushing water to propel the boat? ok this means lower revs but not sure how it works out?

Andrew

RE: What Motor?
 

Cavitation is often confused with aeration. It prevents cavitation(formation of bubbles on prop) by introducing aeration(often improperl called cavitation)

This surface drive setup will tend to aerate once in a while, especially when acceleration, and will need a few adjustments after it is installed/tested. Once properly set up, at top speed it should not aerate or slip.

Pretty much all the new RTR boats use this type of drive, especially deep vees.
Here's a pic of the drive setup. If you search some more you will find many boats use this type of setup. You will also get that rooster tail from this type of setup.

Ryan

http://www.fortunecity.com/marina/hornblower/28/6.jpg