Triple Cat

[LarrysDrifter]

No wrong way taken.Im no expert by any means.Im still learning everyday.Im a bit confused by your formula to calculate rpm.Ive always taken Voltage X KV =rpm.Which with 1800kv on 6s would be 39,960rpm.If I were to run this kv,Id start with X442's and move to X447's.If outrunners make good torque,I see no problem turning a 47mm prop at rpm and pushing enough water to move the boat to speed.The Aligns may not be up to task,given what Ive been told about their reputation.Ill try them 1st and see how they do.

[LarrysDrifter]

Also,its okay for a grown man to get excited about a toy boat.I got excited today when Johnson ran his HPR for the 1st time today.

[madgadget]

Uh oh

It's been my experience that the formula you're using is good baseline but almost always way too optimistic. Basing expectations on the standing voltage of the pack @21.00v or 3.7 per cell would be great. But in practice some of the best cells I've encountered struggle in many situations to sustain 3.2 to 3.5v per cell. So as a rule, just mine, I calculate @ 3.5 per cell x number of cells x kv.

Since water has thawed I got a little device I could send you to play with if you got something rtr. But it's got deans on it. As always these are just my opinions based on my experience. Maybe there is less power in my thunder powers. And all this time I've been going to funflys with a "more 'C' than yours" TP sticker on my heli case....

Also,its okay for a grown man to get excited about a toy boat.I got excited today when Johnson ran his HPR for the 1st time today.

Just proves I'm in good company I guess

[LarrysDrifter]

The sponson transom is a little too thin,so I decided to make these doublers to help support the rear.Johnson gave me a piece of carbon fiber,so I figured Id give it a whirl.Ive never worked with this stuff before,but its easier to work with than what I thought.Didnt turn out too bad.I have enough left,so Im thinking about making my own servo mount for a low pro servo and use a pull/pull system or just use 2 4-40 rods.Havent decided yet as the rudder mounting pad on the rear kind of limits options unless I can find a long servo arm for use with 2 cables or rods.

[madgadget]

Maybe something like a outboard tunnel setup??

[LarrysDrifter]

Hazegry polished my hardware for me. Heres how she looks with out paint.He did a fine job.If you guys want something polished,hes the man to do it.Soon,Ill be actually assembling this thing finally.

[Killer V]

Triple Cat

I think that the build is coming along nicely. The triples are just so awesome. One motor is enough for me. And the polished hardware is not something you see everyday. I can't wait to see the paint, finished product and test run results.

Continued success on a fine build.

Jeff

[JPriami]

Looking really good Larry. I need some of that CF plate to make reinforcements in the back of my sponsons where the drives go out too.

[LarrysDrifter]

WWW.kintecracing.com has it. I got the 2.5mm thick piece.

[Jacked1]

I like the shiny outdrives! What are you planning on battery wise?

[LarrysDrifter]

Finally have a mock up of one side.The physical size of the motors with the jackets dont really give me much room to angle the motor before it hits the hull,so I had to bend the stuffing tube like you see.I know there should be as little bend as possible,but Im kind of stuck with this.The flex turns fine with no binding or much resistance.Anyone have an opinion on my stuffing tube bends?Im using .187 cable with 9/32 brass tube.Any opinions or suggestions are welcomed.

[LarrysDrifter]

Thanks,Jacked. Im still undecided on how Im going to do the batteries.At first,I was going to go 6s1p (two 3s packs in series) for each motor,but I think it adds too much weight.This is going to be a heavy boat when done,so Im thinking of other ideas for the batteries.

[Jacked1]

I was thinking the same amount of batteries (6s3p total) for the motor/esc configuration I have been planning for my genesis but thinking of it being too much weight. Do you have an idea of how many amps each motor will be pulling? If it is under 130a per motor you could go 6s2p 5000mah 40c batts total.

I am tempted to get some weights and go to the bath tub with the hull and see how much it can hold!

[LarrysDrifter]

I really dont know about the amp draw. Ive heard these motors get hot easy,but since theres 3,they may be fine.I plan on a motor swap anyway if I dont like how these run or if they do get hot.Im fine with a heavy hull,but not overly heavy-say 15-20lbs.

[Jacked1]

Yea 15lbs+ would be pretty crazy for that hull.
Keep up the building! I wanna see how it runs!