RE: Predator outrigger [project]
 

so, can anybody advice about li-po's setup? please :(

RE: Predator outrigger [project]
 

go with 7.4v because if you use 11.1v then ur gonna end up using a tiny prop. (x427) lol.

RE: Predator outrigger [project]
 

Ok there we go!

The ESC 60-70A w/o Bec was suplied with aliuminium plate and sticked to transistors with some white sticky strip.. as I could not make water cooling and weld tubes to aluminium I decided to change it with copper ~1mm thick plate. Before placing plate on transistors I spread some low thermal resistance paste (like used on CPU and radiator...). Solded two copper tubes to the surface of the plate.. To waterproof all electronics I use some "plactic spray" used to circuit cards etc. It places a thin transparent layer of some plastic all over the place..
I put feigao water jacket on the motor. As there was no place for water lines to go from upside I had some hard work connecting them underneeth the motor. That way I saved some space.
RX is in the small baloon "trapped" in some foam. Bec shares same power source as the engine (is it bad?). There was quite a task for all the stuff to place inside the hull.
Overall weight is near 700grams ~24 oz.
Tried it the bath. CG seems to be just a litlebit too far to the bottom. Engine is fed with three paralel packs and gets 7.4v 3900mah 20-30C li-po. Engine spins like it had no disturbance in the water :D awesome engine.
But one problem I've faced already - the water dont go through the cooling "system" :( I'll need to adjust water pickup as without it esc and motor would die quite quickly.
Allso triming and prop testing will take place soon :) will try to film ...
All thingh like hull cuting, taking it together, firewall making, water lines, water pickup, ruder, prop shaft, stuffing tube, fiberglass engine hood, and some other mentioned earlier things were made myself :)
Thoughts wellcome. :)

RE: Predator outrigger [project]
 

those lipos are going to be SHOT.
that motor will pull like 90 amp. those lipos just can't deliver !

RE: Predator outrigger [project]
 

well... 3900mah and 20C can deliver around 78amps, and burst 30C can deliver 117amps. so where is the problem?
besides, i've tested boat in the bath for around half a minute ful throttle.. engine and esc gets hot without water cooling quickly, li-pos were absolutely cold.
;)

RE: Predator outrigger [project]
 

:D:D:D:D:D

RE: Predator outrigger [project]
 

A good idea for safe operation is to pull Half the C rating of the battery.
Trust me.

RE: Predator outrigger [project]
 

ok thanx. I'll try to use smallest prop I have to check how li-po's behaves on longer runs, than try bigger ones..

RE: Predator outrigger [project]
 

Careful with that LiPo. Typically a LiPo will deliver 80% of the rated c rating without any problems to worry about. In your case, that would be about 60A. I wouldn't trust that LiPo in a boat that is capable of drawing close to 100A.

Ryan

RE: Predator outrigger [project]
 

Ok. Afterall I'm going to use 3 or 4 A123 cells soon. These will do the job I think..
How is the job afterall? :)

RE: Predator outrigger [project]
 

First test at a lake!! :D OMG that thing flies!
(sorry but my camera died after i turbed it on [:@] )
at ~minimum throttle it goes on float, goes straight, good control.. when I pushed half throttle my jaw fell [X(] this engine is really really good :D
As I tried to go full throttle (to the shore direction) I thought that it would stop, but it struck a sand on the shore and broke rudder. Also when I opened back cover I saw twisted flex cable :( . I think this happened to lack of lube, or the cable wind direction played the part... so some fixing is on the way. The batteries vere cold, engine and esc a bit warm..
I only managed to test one smallest prop y531..

RE: Predator outrigger [project]
 

electric = motor. Gas or nitro = engine. that motor is not an engine, just letting you know.

RE: Predator outrigger [project]
 

Same problems continues..
Second flex shaft broke again! :(
I'll put a short (very short) video of starting the run...
Flex shaft broke about 20meters from shore, had to ask fisherman to catch my boat :D rigger was in water quite a long time, but no water drop inside :)

this time I'm making a steel wire flex shaft as someone used in N1 rigger I think. The winding dirction of the cable played the part, because as I removed the broken shaft it was unwounded! so it just become loose and twisted near coupler.
I'll make this baby fly !! [>:] [>:]

RE: Predator outrigger [project]
 

well why is there flex open with just teflon ?
the brass stuffing tube should be right up against the collet or close to it.
I make mine so that you have to remove the motor to get the collet out
what size flex and prop?

RE: Predator outrigger [project]
 

That is a typical sign of winding the flex the wrong way. They won't snap if the proper setup is used. I still prefer flex as opposed to wire drive for several reasons.

Ryan

RE: Predator outrigger [project]
 

Well, It is my first try to make everything from zero :)
flex cable ~ .125 or ~3mm.
Prop used plastic octura Y531, allso have Y534 and X632.

RE: Predator outrigger [project]
 

Yes indeed... if there was a slow boat, with weak engine, it would work, but with this feigao :D no way...

BEsides!
My new shaft (at last) did the job fine! and boat goes!

Don't know what speed it goes on the moment, but I'm very pleased with this setup and what I did.
Don't know the run time exactly, but it is quite long..
Few problems came: water goes through stuffing tube, steering is quite bad on medium and high speed and esc is quite hot.
What to do with steering?
don't know if there is bad water circulation on esc cooling or engine is just too powerfull. (esc 60-70A w watercool)
After runs, engine is a bit warm, bateries cool, esc quite hot.
Answers wellcome ;)

VIDEO link http://www.youtube.com/watch?v=YZV5mJsZd6M

RE: Predator outrigger [project]
 

Hi,
hm.. nobody bothered to answer.. :)
Well I'm moving further and I'm going to add a duralumin fin on one or both sponsors.
If I add one, on whitch it is best to add? left or right according to my setup..?
And would it somehow degrade performance if I'll add fin on each front sponsor? (a bit smaller etc.)

Thanx.
p.s. can anybody tell what speed my rigger goes on video? :]

RE: Predator outrigger [project]
 

Add a hydro fin to the right sponson and only make right turns.

Ryan

RE: Predator outrigger [project]
 

kinda hard to tell with a vid, especially the way you taped it. and i dont know if you sped up the tape to make it look faster.(which in my opinion is really stupid). i would guess your in the low 40s. looks fun too, i think youve inspired me to leave the mono world, lol

RE: Predator outrigger [project]
 

Thanks for the ansvers.
And, no, I did not speed up the "tape" :))
I've allready made the fin :) will put octura x632 prop this time and will try to film..
I've also made a small discovery about SS rot shafts... As I said earlier I've made one, it worked well, and another big advantage, that it does not take the stufing tube shape after a week being in one. I took shaft from stuffing tube today and it was absolutely straight! that mans that you don't have to disassemble the shaft etc. after runs :)

RE: Predator outrigger [project]
 

just watch this vid lol.[link=http://www.youtube.com/watch?v=TihqKiQ58iQ]watch the bird at 36 and 43[/link] i dont think birds can fly that fast, and the handling is insane if it is not sped up. lol

RE: Predator outrigger [project]
 

Its not sped up. Thats normal for lipo powered boat.

RE: Predator outrigger [project]
 

did u look at the bird at 36 sec. and 43 sec.? they dont fly near that fast, and btw, i realize boats can go much faster than that too. 140mph... whats next, lol. they can haul. and i realize it. it is possible that it isnt sped up but if i were to guess, its sped up.

RE: Predator outrigger [project]
 

Dude, even a seagull can fly up to nearly 40mph. That's definitely not sped up.

Ryan