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[matty]

Hey Martin,
 
just going back to the post you sent with all site info on brushless controllers, some links are plane controllers, are you suggesting i cool them with tubing down both sides and battery pack shrink tube ??

[Martin (Admin)]

That could be an option but if they are built to take that kind of power, in a plane
they would only be cool by free flowing air. They may also have water cooled versions if asked.
Watercooling an air cooled version shouldn't be too difficult but you'd be on your own!

[matty]

thanks m8, i've seen it done many time's but your right, really its best to buy a version already watercooled and not waste time trying to make something into something else...    i have a habbit to do this as a modeler 

If you come up with anything else like secondhand controllers over 120 amps and up to 30 cells drop me a message please.

Thanks again

[Martin (Admin)]

Is this what you your boat to do?....

http://www.youtube.com/watch?v=D0sqKIjoUcw

[matty]

 

yes something like that....lots of speed with nice air pocket under the boat....if only i get the shaft to stop vibrating i could maybe possible.....

also jumps are good
http://www.youtube.com/watch?v=E6VJJfSaOYw

[john54]

Hi does the shaft vibrate only off load?
  Most fast electrics when running dry I have found the shaft  tends to whip which can cause a lot of damage!
  Don't forget normally when the boat is running wet you will lose between 10% and 20% of the revs  with surface drive and a lot more with subdrive.
 One way that might stop this is to put some bracing on the shaft and mounted it using silicone which tends to dampen the vibration quite a bit
 when I converted my jetstream to brushless I had the same problem so I use silicone to bond the motor mount and also a brace block halfway down the prop shaft.
 it made a lot of difference the silicone virtually damped out  nearly  all vibration and she was so quiet it was unbelievable :) I hope this helps

[matty]

Hi John54, on low revs its smooth, then giving more gas the shaft vibrates hard and when looking at the prop you can see it move left to right, i had same prob just 2 weeks before so i took out the shaft again to fix the it, when gluing the shaft back i used a rubber grommet in place of glue (the side of motor) and now its much worse  :'(
I use a two component glue from UHU powder and glue and never had this prob before, what's the name of your silicone ?? for all purpose or window, metal ?? there are many

[john54]

Hi
This is what i use 
Looks like its made in your part of the world :)

[grasshopper]

rumour has it that the fastest ones were starting to use turbine engines from helicopters. Reading the links above, the early boats were using Merlin engines (12 cyl 27 litres) or the american equivalent (packards?) and now are using helicopter engines from Chinooks...

[BJ]

What motors do those Unlimited / 'Top Fuel' hydroplanes use these days?

I was going to refer you to Roger Newton as the expert on this but I came across this post on Rcuuniverse that Roger has died
http://www.rcuniverse.com/forum/m_7828116/anchors_7828500/mpage_1/key_/anchor/tm.htm#7828500. He also worked at the Hydroplane Museum in Seattle (??)
I have used his plans to make a couple of 1/8th scale hydroplanes and there used to be a picture of a couple somewhere on Mayhem.
See also http://www.abrahydroplanes.com/, from this site the engine on U1 is a Gas Turbine hence the 200 mph figures on the water.
U-1 Ellstrom Elam Plus is detailed as
Owner: Ellstrom Family Seattle, WA
Driver: Dave Villwock Auburn, WA
Homeport: Ballard, WA
Website: u16hydro.com
Length: 29' 4"
Width: 14'
Weight: 6350 lbs.
Engine: Lycoming T-55/L-7C Turbine
Engine Builder: Tracey Bratvold Hamilton, MT
Crew Chief: Erick Ellstrom Seattle, WA

[8316dart]

Hi,

I've just built up a Diabolo and took it for it's first run yesterday.

It is fitted with a Graupner 700BB motor, Ripmax Seasprint ESC and here is the important bit, a 42mm Surface Piercing Robbe propeller, not a speed prop which I think yours has.

With two old but freshly charged 7.2v sticks the Diabolo cavitated briefly then quickly climbed on to the plane and was accelerating when she had to be turned due to the limited test pond size.

I have also got a Magin One which I had horrendous problems with, as all it would do was cavitate, until my local model shop suggested the surface piercing props.....He suggested that I could try up to 50mm, which I will do when I can find the props.

Hope this helps!

[martno1fan]

What motors do those Unlimited / 'Top Fuel' hydroplanes use these days?

I was going to refer you to Roger Newton as the expert on this but I came across this post on Rcuuniverse that Roger has died
http://www.rcuniverse.com/forum/m_7828116/anchors_7828500/mpage_1/key_/anchor/tm.htm#7828500. He also worked at the Hydroplane Museum in Seattle (??)
I have used his plans to make a couple of 1/8th scale hydroplanes and there used to be a picture of a couple somewhere on Mayhem.
See also http://www.abrahydroplanes.com/, from this site the engine on U1 is a Gas Turbine hence the 200 mph figures on the water.
U-1 Ellstrom Elam Plus is detailed as
Owner: Ellstrom Family Seattle, WA
Driver: Dave Villwock Auburn, WA
Homeport: Ballard, WA
Website: u16hydro.com
Length: 29' 4"
Width: 14'
Weight: 6350 lbs.
Engine: Lycoming T-55/L-7C Turbine
Engine Builder: Tracey Bratvold Hamilton, MT
Crew Chief: Erick Ellstrom Seattle, WA

Hi mate what motors did you use in your 1/8th hydros,have you seen mine built from a zippkits kit its semi scale full mod zenoah.Id love to see yours any pics?.
http://ca.youtube.com/watch?v=sP0L-Fb1RLk

[matty]

 
Hi guys sorry long time...just bringing my Diabolo thread back online.....

Was wondering guys.....a modelshop here in Belgium has closed down and i was offered a 200euro Graupner Carbon 70 = 50,000rpm for 60 euros, very nice price, my poor Diabolo sits on the shelf again after not enough cash to splash out on my hobby.....would this motor work for insane speeds after fitting a water jacket, normaly i think its for planes....

Also if anybody is interested i think i will sell my new Hydro T4 unbuilt.....price is high.....i paid just over 1000euros for all the bits + hull + Lehner 2250 9winds special edition + all running gear in super polished Alu all is there. Its a big shame but me got a 16month old baby girl and my hobby has slowed down...      pics are on this thread, it is a beautiful boat, i love it.....but its sat there for 4 years, i will say it has everything except the speed controller and ofcause no servos or transmitter, this is purly new untouched 120kph Mayhem, ive seen the vid of this Hydro take of the water like a plane... it was bought from Germany http://www.hydromarine.de/ just the hull without wing is 345euros...
so if anyone is interested its the T-4 Miss Bud 24-26 cells or 6-8 LiPos 4000-5000 mAh / 30C min, the hardware without motor an prop is 153euros, motor was 370euros, you will need atleast 150-160 watt speedcontroller to run this motor.....this is for the big boys guys...... , so please drop me a message.....thanx.... oh i will see about a price if any interests, but only serious deals guys...