Dual Rudders on Pro Boat Mystic

[gyrotron]

120man,

I'll see what I can do about my brother's Impulse dual rudder pics. He took the boat with him.

I got pics from my brother's Impulse dual rudders. Here is what we did, take a look:

[gyrotron]

I modified my Mystic 29 "Minus-Two" to accept the Impulse 31 rudder mounting system with the IM31 straight faced rudder. Lightened the handling up in the turns quite a bit going from the slanted rudder to a straight blade.

Darin,
Where can we get the IM31 straight faced rudder? Can you post pics of your modified Mystic? Thx.

[Garrett]

what do you mean "minus two"?

[120man]

Great info- THANKS darin. Sure looks like the tie rod will end up right in the prop blast. Didnt realize the angled rudder drives the front down. At least I can say today I learned something.

[Garrett]

Hey, If you guys look at this, it appears that the tie rod is in the same position that I would have mine on the mystic. just an idea. but would like some feedback.
http://www.offshoreelectrics.com/pro...rod=dh-prb4253
Darin- Whats the difference between the angle faced rudder and the straight faced rudder? Could you post pictures showing the difference? in the pictures I'm looking at they look the same. Also, Dual rudders with a three blade (lifter) propeller. how do you think it would effect the drag, ride, hydrodynamics...etc

[Darin Jordan]

Darin- Whats the difference between the angle faced rudder and the straight faced rudder? Could you post pictures showing the difference?

The difference is that a straight rudder has a straight (up/down) leading edge... and an angled has a tapered leading edge. The later has a similar effect to cambering the rudder back (bottom further back than the top)... It pushes the nose down when it's turned (lifts the back). Cambering the rudder forward lifts the nose in a turn (sucks down the back).

The IM31 comes with a straight faced rudder. Here is a shot of the IM31 hardware on my Mystic 29 "Minus-Two" that I built to race at the Nats. The rudder in these pics is a modified Mystic rudder, but I swapped it out at the race for an IM31 rudder and it worked better in the turns...

[Garrett]

why did you take off the rear platform? was it to shave some weight?

[Darin Jordan]

why did you take off the rear platform? was it to shave some weight?

Hahaha... No... It was to make the boat legal to run in N2... 27" maximum hull length... Using the IM31 hardware, however, put the prop right back where it started, and I didn't have to tough the ride-pads to do this...


Here is the original thread: http://forums.offshoreelectrics.com/...uot&highlight=

[Garrett]

So Darin, do you think if I use the Mystic rudder strut with the Impulse rudders it'd have less drag? if so would the impulse rudder fit between the mystic bracket?

[Darin Jordan]

So Darin, do you think if I use the Mystic rudder strut with the Impulse rudders it'd have less drag? if so would the impulse rudder fit between the mystic bracket?

I don't know, and no, I don't think they are a direct bolt up... The setup I used above is ALL IM31 hardware, with the rudder blade only from a MG/Mystic, and that rudder blade had to be modified (cut out mounting and two holes drilled) to make it fit the break-away attachment/pivot for the IM31...

All of these factory rudders are a bit thick for my taste, but shouldn't really slow you down much. Just make sure to sharpen the leading edge. They are blunt from the factory.

[Garrett]

Good to know, Thanks Darin.
And guys, if you have anymore ideas on the topic please post them.
Pictures are awesome. Ill post my pictures as soon as I get my parts.

[Garrett]

IMG_20120828_172818.jpgIMG_20120828_174945.jpgIMG_20120828_175159.jpgIMG_20120828_175300.jpgIMG_20120828_175312.jpg

1st I put the two brackets on the hull, then Marked where the 2 water tube holes went, plugged the existing hole with marine grade caulk, then after it dried, I then installed the rudders onto the transom, along with the water pickup tubes, I got a Traxxas Jato Turnbuckle/Toe in Link, and thats how I tied the rudders together.

As for the ESC it had dual water fittings on it, so I bought some y fittings and split the tube.

[Garrett]

IMG_20120828_175351.jpgIMG_20120907_143756.jpgIMG_20120907_144146.jpgIMG_20120907_144157.jpg

[120man]

Excellent work, looks good. Let us know how well it functions. I was thinking if it tends to drive the nose down in a turn maybe you could tip the whole assy. back some to counter that.

[Garrett]

I finally got Mystified. lol. just a quick clip of how the boat ran with the new ESC and the dual rudders. Sorry for the short video, but I was holding my cellphone (Camera) in my right hand, and the transmitter in my left hand.
Theres a decent shot @ 1:14 that shows how the tie rod is positioned on the rudders.

http://youtu.be/byOIuE8YORQ