Advice wanted for Catamaran project

[dyslexicdaver]

I’m starting to plan my next project and was thinking of a catamaran like the Toysport Jollycat or H&M Maritimo

I’m looking for some suggestions / advice from those who have built cats.

My budget will limit me to Nimh batteries, I’m thinking of an 18 or 24 cell set-up.

The first question is, single motor or twin motors (Brushless of course).
What are the pros and cons of each?

If I go for a one motor design (Which I’m leaning towards for simplicity) what is a good Strut / Rudder combination. I would like the strut to be adjustable.
Which works Best, a rudder close to the stern or set back on a long bracket?
What length rudder would be nedded for a cat of this size?

Any other useful tips on building a fast Cat would be appreciated.

Dave

[saleens7]

a lehner 2250/12turn would work great on 24 cells

a feigao 12 or 13XL would work good on 18 cells also...the lehner will have more rpms and tourque behind it so it will run a bigger prop...the esc would be a 40-160...its kind of expensive, but worth it....you can also try some more cells (like 20) on the 13XL....that way you could still be able to use the feigao and the hydra 120 esc and not have to pay so much for the lehner and schulze...

[Eyekandyboats]

ok. . . one thing.
you do not need a 40-160 for that motor what so ever.
a hacker 77 or a CC125 will do the job just fine

[saleens7]

cc125 wont handle 24 cells

ive never seen the specs of a hacker 77, so i dont knaw about it

the 40-160 was for the lehner 2250 and the 24 cells

[SJFE]

I hope you don't plan on starting it any time soon. Both of those hulls are very hard to come by.

[Fluid]

The Hacker77 is a great high voltage sport controller. A bunch of local guys run them up to 32 cells and so far no one has been able to blow up the new version (square). Other quality options include the Castle HV110, BK3670 and BK3695. :)

There is nothing wrong with using a poptart for that motor, but it is costly and not waterproof. Like anything else, how fast you go depends on how much you spend. The 40-160 is bullet proof and can handle almost anything....except water.

.

[RMZDADDY]

I run a 12xl, hacker 77(10-32 cells), 1.26:1 gear drive, and 24 cells in a Aeromarine Mean Machine. The hull is about 5" shorter than what you are looking to get, so my setup might not be suitable for a hull that size. Mine weighs about 7.5 lbs with batteries. I have pics and a vid of mine in the member galleries at rcflix under the same screen name.

[hammertime]

im running my bk badit s 30" boat...... i have the sv motor on 14 sells and its fastest run so far was the other day at 43.8.... not too bad you dont need a lot of cells to go fast.... just set it up right........ also the inline strudder on here would be a good choice for running a lower cell count like this.... i love my boat right now......... video will be on here soon strugglin to find a camera

[dyslexicdaver]

I run a 12xl, hacker 77(10-32 cells), 1.26:1 gear drive, and 24 cells in a Aeromarine Mean Machine. The hull is about 5" shorter than what you are looking to get, so my setup might not be suitable for a hull that size. Mine weighs about 7.5 lbs with batteries. I have pics and a vid of mine in the member galleries at rcflix under the same screen name.

RMZDADDY

Like your Mean machine, are you happy with this hull? The flat transom looks like it would make attaching the hardware easier than on some other makes. What made you choose to run with a geared transmission?

Dave

[dyslexicdaver]

im running my bk badit s 30" boat...... i have the sv motor on 14 sells and its fastest run so far was the other day at 43.8.... not too bad you dont need a lot of cells to go fast.... just set it up right........ also the inline strudder on here would be a good choice for running a lower cell count like this.... i love my boat right now......... video will be on here soon strugglin to find a camera

Hammertime

Your right about not needing extra cells to go fast, when I added more than 12 cells to my syncron the extra weight cancelled out any extra power advantage. I was thinking 18 to 24 cells to play with a set-up which is completely different to my 12 cell mono’s. but still in the early planning stages and might end up with a different smaller hull.

Dave

[dyslexicdaver]

I hope you don't plan on starting it any time soon. Both of those hulls are very hard to come by.

SJFE
I'm Not in any immediate rush there’s a lot of new stuff I will need to buy for this project, as I’ll need new battery packs (thinking of the IB3600 from battlepack) Upgrade battery charger. And my CC125 & Feaigo 10XL motor will probably need upgrading.

Steven V, When do you expect to be getting any more Jolly cat hulls in Stock?

Dave

[RMZDADDY]

Dave, I'm happy with the hull so far, the video was the very first time that boat was in the water. I was quite pleased for a first test run. Everything(including the batteries) ran very cool. I've since moved the CG forward and found it doesn't tend to flip and turns much better. On sunday I will be testing with an X640 and possibly an X642 if temps and amp readings warrant it. Based on how cool everything ran the first time I feel it can be considerably faster with a prop change. In regards to the trans, I like having the ability to make small incremental gear changes to gain speed while monitoring temps and amp draw (with a Watts-up meter) to get the most out of the set up. I have heard that for competition, the trans can be a weak link due to gear failure. I make sure to check gear lash before each run to prevent that from happening. I have run the trans in my Toysport Triton for a year now and have not had any problems at this point. If The weather holds this weekend I'll be posting the results and video.

Tim