Twin powered carbon Rivercat build

[kfxguy]

I've been putting off building a twin. Why? I dunno. I guess I get bored quick and it it takes too long I'll lose interest. Maybe I'm just in denial? I dunno, but I can't back out now. I've been collecting stuff since my other Rivercat sank to build this. I also have another single I'm building but the motor is being custom made so that's gonna take a while. I've already collected everything I need for this one so I guess I might as well start before I back out again haha. Anyway, here's the plan:

Castle 1415 2400kv motors
Seaking 120's with castle cap banks
Lhs waterproof servo
Ose .187 flexes
Custom built ball bearing drives.
32" carbon hull
Octura stainless collets
Center mount rudder
Carbon motor mounts. These are neat because you put screws in the motor, slide in the big holes, then twist the motor a tad and tighten
Ose cooling jackets
Cnc 442 props to start then abc 1615-17-45 counter rotating beasts after
3s or 4s pack per motor
Dual cooling

[kfxguy]

I just got through making the drives. I'm using carbon tubes. One size the 5 ball bearings go into. Then there's a tube epoxied into the larger tube that the bearing back up to and the 1/4" brass slides in. After much research and talking to Rocstar and Keith, I've decided on fixed drives. They will be fixed level. I'll have to make any adjustments with Cg and prop choice/mods.

[kfxguy]

It's sitting in a bucket of water right now. Poured 20 grams of epoxy and chopped Carbon in each tip and the tunnel. The water helps to keep the heat down in the tips while the epoxy cures

[dmitry100]

You sure love those rivercats, man!

What kind of inlay are you going to be doing for it... CF? Wouldn't mind to see how you lay that stuff down on that thing if you are.

[shua]

Very nice! subscribed!

[kfxguy]

You sure love those rivercats, man!

What kind of inlay are you going to be doing for it... CF? Wouldn't mind to see how you lay that stuff down on that thing if you are.

Yea I guess so, I had a couple more of these hulls so why not? Lol. I'll be doing a regular weave carbon inlay in it. What did you want me to show?

[Apophis]

Uh oh, you know what they say, once you have twins you never....

Oh wait that's something else

Travis building a twin, something must of froze over lol!

Looking forward to the build, curious to see your drives.

[kfxguy]

Uh oh, you know what they say, once you have twins you never....

Oh wait that's something else

Travis building a twin, something must of froze over lol!

Looking forward to the build, curious to see your drives.

Lol. See those two carbon tubes with the bearings? That's the drives, not much to them. They will be braced at the overhang of the transom. I may end up switching motors but these will do for now. I figure it should do 70ish on 4s per motor. Heck, my little mono is doing almost 62 on 4s with one motor so I'm sure it's doable.

[dasboata]

try 2 part foam Travis I have been using it for 30 years in model boat builds it adds strength and flotation, I also use it around the hull to deck joint to straighten it I do use Aeromarine brand but pretty much all the same, just don't use great stuff home depot stuff,,,,,,,,,,,,, LOL http://www.ebay.com/itm/Two-Part-Liq...item1a01eb1660

[kfxguy]

try 2 part foam Travis I have been using it for 30 years in model boat builds it adds strength and flotation, I also use it around the hull to deck joint to straighten it I do use Aeromarine brand but pretty much all the same, just don't use great stuff home depot stuff,,,,,,,,,,,,, LOL http://www.ebay.com/itm/Two-Part-Liq...item1a01eb1660

That's all I use. I've been using us composites 2lb foam but I had a "foam day" Saturday and ran out so I ordered some from elite motoring on eBay. I had to do 4 boats Saturday so I used up a lot. I did an experiment yesterday.....in one of my boats you can see the foam and the tan color looks bad....so I added some black epoxy dye to it....turned it carbon grey. Worked perfect so I may be doing this for now on....

[dmitry100]

dasbota: Whats so bad about the Great Stuff foam to fill the void in the tips? Is it too heavy of a foam?

[kfxguy]

dasbota: Whats so bad about the Great Stuff foam to fill the void in the tips? Is it too heavy of a foam?

The way it expands is from oxygen getting to it...so what happens is the area exposed expands first, hardens and then the inner part slowly hardens. It takes the path of least resistance, usually busting open the hull. And I speak from experience, I had an extra hull and tried it. Yea, never do that again. The two part works great because it cures from a chemical reaction.

[dasboata]

dasbota: Whats so bad about the Great Stuff foam to fill the void in the tips? Is it too heavy of a foam?

Plus the pour in makes for a very nice finish,,, the great stuff will expand more when you bring the boat in the sun !

[dmitry100]

dasboata: Do you know if they sell any of that Composite foam in smaller amounts? like 2LB worth? or is the 2 part foam from Kintecracing for $10 bucks just as good?

Product description of the one from Kintec:
"Expandable Marine Foam: This expandable 2 part polyurethane water proof flotation boat foam is low density and closed cell. It weighs 2 pounds per cubic foot. Each kit contains 3oz of each part A and B. $10.00 per kit."

[kfxguy]

Got a little done tonight. Didn't get the inlay done but got the carbon cut out. Then I laid several pieces in the transom area. Hard to get in there so I had to do it in pieces. I also made a thick aluminum plate that reinforces the rudder mount area and I can drill and tap right into it. If you e ever had to get to the nuts in one of these hulls, you know why it's easier this way. I flooded the transom area with epoxy and chopped carbon fiber too. Im going to put epoxy and chopped carbon in the bottom of the sponsons where it recesses. Nothing special but the little plate I made.

Got a little done tonight. Didn't get the inlay done but got the carbon cut out. Then I laid several pieces in the transom area. Hard to get in there so I had to do it in pieces. I also made a thick aluminum plate that reinforces the rudder mount area and I can drill and tap right into it. If you e ever had to get to the nuts in one of these hulls, you know why it's easier this way. I flooded the transom area with epoxy and chopped carbon fiber too. Im going to put epoxy and chopped carbon in the bottom of the sponsons where it recesses. Nothing special but the little plate I made.