Maritimo (Single motor build) [Archive] - Offshore Electrics Forums

View Full Version : Maritimo (Single motor build)

dyslexicdaver

10-26-2007, 09:38 PM

Hydro & Marine Maritimo Catamaran (Single motor build)

The inspiration for this layout was from a Maritimo Cat that was built by Ray Schrauwen, whose project puts mine to shame.

Design parameters.
My budget did not stretch to twin motors so decided on single motor set-up.

Motor is Feigao 14XL (but have options of using 10 or 8 winds)

Esc is CC 125, which I already had in my Syncron.

Rudder , I wanted to go with an in-line rudder, originally opting on a MHZ Hydro In-Line Rudder but was not able to get this due to stock availability.
So I decided on a speedmaster rudder which I then modified the bracket & strut to make almost in line (offset by 1/16 inch)

For the dive shaft I opted for 3/16 flex cable to cope with any increase power in the future.

Batteries
My original choice was to start with NIMH cells 18 or 20. But when I first tested the boat the Intellect 3000 cells I had would hardly get the boat up on the plane.
So next step was LIPO , I now have two 3S thunder power extreme packs that will be connected in series. (I can then run these in parallel in the Toysport Syncron should still be fairly fast but give long run times)

Step 1 - Built structure for mounting Motor, Servo receiver & reciever battteries

I liked Ray’s set-up for mounting the Motor and servo in a single framework, I was not able to get hold of any Carbon sheet or similar so opted for using Aluminium to build the frame (light weight was not a primary concern as I had read that this size Cat can suffer from flipping if to light)
Also it was easy to work with the Aluminium.

Step 2 - Modify Rudder and Strut

Modified the brackets holding the rudder so the strut was close to being in-line, it’s actually off set by 1/6 inch.

Step 3 - Battery placement.
I’m still working on the battery placement and how to secure them. I have made some fibreglass brackets, which are epoxied to the hull and am currently looping velcro though these.

So far from tests best performance is with the batteries as far back as they will go.

I’ve posted pictures on RcFlix
http://www.rcflix.com/photopost/data/605/Side_view.jpg
http://www.rcflix.com/photopost/data/605/Front_View.jpg
http://www.rcflix.com/photopost/data/605/Rear_View.jpg
http://www.rcflix.com/photopost/data/605/Rudder_Strut_side_view.jpg
http://www.rcflix.com/photopost/data/605/inside_from_side.jpg
http://www.rcflix.com/photopost/data/605/medium/Battery_tie_down_brackets.jpg
http://www.rcflix.com/photopost/data/605/inside_with_batteries.jpg

NorthernBoater

10-26-2007, 11:45 PM

What is that red loop on the back of the boat. That boat will be very under powered running on 6s with the 14XL. I would suggest at least a 11XL or 12XL for that setup.

Mich. Maniac

10-27-2007, 12:00 AM

nice job, like how you had room for sponges. Also nice stand for that boat and hardware.

hkusp45

10-27-2007, 12:23 AM

The red loop is a safety loop. When you pull out one end it removes all power for the ESC. They work great!! BTW nice build!!

dyslexicdaver

10-27-2007, 12:55 AM

What is that red loop on the back of the boat. That boat will be very under powered running on 6s with the 14XL. I would suggest at least a 11XL or 12XL for that setup.

The loop is a safety cut-off loop, you pull the loop to cut the power in an emergency or if you want to change props without taking the tape off the cover.

I started with the 14xl to make sure I did not use to much current with the speed controller.

Top speed so far is 45.9mph on a X645 prop, which had a max 92 amps.

tomorrow I'm starting to test with the 10xl motor

NorthernBoater

10-27-2007, 01:37 AM

What were the motor temps after the run. Drawing 90 amps on the 14XL is higher than what I would recommend for that motor. The lower turn motors can handle higher amp draws.

dyslexicdaver

10-27-2007, 05:33 AM

What were the motor temps after the run. Drawing 90 amps on the 14XL is higher than what I would recommend for that motor. The lower turn motors can handle higher amp draws.

The motor temp was 44C, only ran for a minute or 2 on that prop just to see what it was like most of the time was with smaller props 37 or 42mm

SJFE

10-27-2007, 10:23 AM

hkusp45

10-27-2007, 05:01 PM

I have run my cc cuda 125 on 6s with no problem. It Is watercooled with plates

dyslexicdaver

10-27-2007, 06:04 PM

Dave,
How many times have you run 6s & what are your ESC temps like? The CC 125 is rated @ 24 volts. 3s packs fully charged are just over 12 volts so you are right at the limits. I ask because my Hex120 is rated @ 25v and I had planed on 6s but didnt want to burn it up. I know the controllers are diffrent but probably not very much. If you continue to pull it off I may move up to 6s.
Thanks
Tom

Tom

I've run it on 6s 6 times now, max temps between 36 & 50C. None of these were continual usage. but with a prop that keeps the amps to 70 max the esc is not getting above warm.
Dave

SJFE

10-27-2007, 07:58 PM

Thank you Sir :wink:. That is some valuabe information :).

Fluid

10-28-2007, 01:12 AM

Castle rates the Barracudas and Hydras to 6S LiPo, that is not a problem. I believe that the 10XL will not be happy on 6S in a large boat like yours. You will have to run a small prop to keep the load low, and that reduces prop efficiency and thrust; accdeleration out of turns may be sluggish.

Clearly you are not underpowered with the 14XL, and there will be a limit to the speed you can get within runtime and/or amp draw limitations with a lower-turn motor. A larger-format motor on 6S is the real answer if the 14XL is not enough.

.

SJFE

10-28-2007, 10:52 AM

Fluid I had not considered the load the 10xl. I am running a 9XL in the Jolly. Even though my boat is a couple inches shorter and a pound and a half lighter 6S maybe pushing that feigao a bit to hard. I am unable to afford a Neu at this time. Maybe I shoudl look into one of the KBL series motors if I plan on 6s. Thank for bringing the motor issue to our attention.