real fast micro boat...

[nowing]

see movie 1

see movie 2

see movie 3

hull : micro mogli(400mm)

octura x431

jeti 80amp

motor : feigao 38084-9s bl motor

batt : 9cells(GP 4/5 sub-c size 2200mah)

Hitec mini servo

 

[Propjockey]

Dude! That's cookin'! What kind of run times are you getting with that setup?

 

[nowing]

full power with 4/5 sub c size 9cells... about 3-5minutes

this is the boat on movie

 

[Ronald van Essen]

He guys,

Although I am a nitro freak I thought you might wanna see this, from Schwarzenegger-country:

http://www.speedtoy.com/Speedtoy%20Powerboottreffen.htm

Its quite along video, but he, some boats do it upside down.

Ronald.

 

[Scott Norris]

The electric boats are getting more amazing every day.

 

[Propjockey]

Awesome video, Ron!

(you might want to pour a cup of coffee and grab a smoke before you start....it's long!)

There's a bunch of things I've never seen before. Apparently they don't have cell restrictions. Some of the cats are just graceful--for lack of a better word.

 

[Speed Jr.]

Those huge cats are amazing. I just dont understand the lack of run time. None the less, impressive.

Larry

 

[jayt]

I just dont understand the lack of run time....

Two reasons - first, at that event the boats were set up for maximum speeds and drew a lot of amps, sucking the power out of the cells quickly. Second, because they draw so much power, they create a lot of heat, particularly in the cells and the ESC. Running the cells until they are 'empty' will simply overheat them and eventually destroy the packs. Getting the ESC too hot will cause it to shut itself off to prevent thermal damage.
The problem is made worse due to the tiny lake they are using - it is 'way too small for the speeds of some of the boats and they spend too much time accelerating, heating up the system. That is a problem in Germany - no place to run fast boats. The fastest electric boater in the world is a German and he has to come to the US to run his fastest boats.

The Europeans do have cell restrictions for competition, but a lot of them have built high-cell-count boats for years - 60 to over 100 total cells - and they enjoy running the big boats. Some of the boats shown may be using parallel packs, I didn't look closely enough. Parallel packs (twice as many cells delivering the same voltage) allows a higher total amp draw without damaging the cells.

 

[Speed Jr.]

jayt, I understand with the huge amount of amp draw and heat, all that was meant by this was that its a shame that the run times are so short. The fact that the set ups on the fastest electric boats can only run 2 SAW's at peak power before the batteries loose peak voltage is disheartening. They are amazing in everyway though. The RPM's turned is incredible. Yes, Lake is much too small. About 10 years ago that lake would have been perfect with plenty of room, this just goes to show what technology has done to the sport. I loved the big Cats. Wanted to see some of them riggers, but they didnt show any. None the less impressive.

Larry (yes, a nitro guy)

 

[nowing]

Ron//wow great movie...so impressive!!!

electric boat's scream sound is make me crazy!

sooner or later I will use lipo 11.1V 4000MAH(15C) on my micro mogli...

here's some pics making micro mogli...

making micro mogli gt part 1...

making micro mogli gt part 2...

enjoy boating :lol:

 

[jayt]

...The fact that the set ups on the fastest electric boats can only run 2 SAW's at peak power before the batteries loose peak voltage is disheartening...

Yep, kinda like the fastest nitro guys having to replace the rods and bearings every few runs.....and those pesky glow plugs......so disheartening! Actually, the fastest FE SAW boats don't run out of cell power after two passes - their ESCs get too hot. The big cats can be real amp hogs and get everything pretty hot, but a lightweight rigger comes in with the motor and cells fine - it's usually the ESC which thermals if too many passes are made.

Backing off the amp demands does reduce speeds, but it is possible to run in the 60s for 3-5 minutes with some FE setups and LiPos. And as cell technology continues to improve the speeds and run time will only get better. Ten years ago you only got one good SAW pass before the cells faded....

 

[Speed Jr.]

This is true, good info right there. HAHA, you got me:

Yep, kinda like the fastest nitro guys having to replace the rods and bearings every few runs.....and those pesky glow plugs......so disheartening! (Quote)

This is true also. You electric guys will overtake RC speed records for good with the advancements in technology without a doubt. Im gunna enjoy the sound and smell of Twin Nitro Engines while its still legal. lol :lol: :lol:

So whats next? Super water and air cooled ESC?

Larry

 

[MarkF]

ESC are already water cooled, but if we could hang them out the boat for air cooling well that would be a good thing.

Mark

 

[jayt]

A redesign of current ESCs is in order, IMO. The popular "stacked" configuration of the FET boards does not allow the most efficient water cooling. A few ESC makers (Jeti) are beginning to realize this and are making single-level, flat ESCs. This allows the water cooling plates (which can be markedly improved themselves for more rapid heat transfer) to make direct contact with all the FETs.

Another area is the use of better quality FETs - ones with even lower resistance. This is a win-win since it means more power out of the ESC along with less heat generated within the ESC. As battery technology continues to advance rapidly, the ESCs and motors will need to change to catch/keep up. B)

Hey, I don't want to "get" anyone - I want the hobby to grow with room for everyone! I like the sound of a muffled nitro motor myself, but since that is the single most objectionable aspect of the hobby for non-hobbiests, and because it has caused the loss of so many run sites (both planes and boats), I'll have to forgo it eventually too.