loppol60

if i do 1 engine,conected to a gearbox,so i can drive 2 props from 1 engine.it will be on a 72" mono.must the props be of different rotations or can do them rotating in the same direction ? thanks

PEERPSI

They can be but it's my understanding that you want them turning opposite directions. This would reduce prop walk and make the boat run straight without the normal tendency to turn left.

monsterbrad

You can run them in the same way but you will have issues with turning and chine walk.
For safety I would run the opposite like the Traxxas Villian is.

HendricX

Most gearboxes you can buy have counter-rotation.

You can switch between in or outwards rotation.

Some gearboxes have a 'overdrive' ... that's not for Zenoah's but for Pollini's and Blatta's.

My buddy's [link=http://www.wd200-modellbau.de/?Getriebe%2FGearbox]Werner[/link] and [link=http://www.matho-powertrain.de/webkatalog.htm]Thomas[/link] are making/selling some gearboxes .... if you want help .. just ask.

loppol60

hi guys,ok from what you told me, i must have em counter rotating.now can anybody send me designs so i can have it custom built from a friend as i would like to keep the cost low thanks

HendricX

You will need 4 same size spur-gears ... induction hardened @ 38€ a piece.

That's 152€ for the gears only ... Casing : count for 20 > 30 € for 7075 bar stock ,

add 8 x C3/RS2 bearings @ 15€ (120)

then you have a total of 250 > 300€ on materials as a private person.

Gearbox is not even made than .

So the price of commercially available gearboxes is not that bad.

Home-made foolproof gearbox could look like this :

Dockman

That looks cool.

nvs motorsports

Thats nice been thinking of something similar myself but a real pain to get the belts and gears

loppol60

but cant i do the props turning the same direction and then just turn the rudder or mount the stinger slightly tho the right?

martno1fan

Keep an eye out for this one from this guy its the cheapest ive seen and will stand upto 12 hp .Maybe drop him an email he makes them although he has the cases made in russia i believe.
Mart
[link]http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130321132430&ssPageName=ADME:X:RTQ:GB:1123[/link]

martno1fan

If you wanna do that why not just stick to one motor one prop ? or go with twins .
Mart

HendricX

Ha ha razzfazz ... So it seems Paul F isn't dead yet ?

martno1fan

Hendrix is that Paul Firmin (not sure thats the correct spelling) aka PIP nimrif models [X(].
Mart

w3bby

Hej Mart, do you recommend PiP/Nimrif or not, just looked at [link=http://www.rcuniverse.com/forum/m_9027530/tm.htm]this thread.[/link]

Just yanking your chain

martno1fan

I wasnt aware this was him but if thats what HendriX is saying then no coment lol.
Mart