My 4.3m solar powered catamaran project

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Jan 28, 2015
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Hi people. I just thought I'd introduce myself, and my latest project. In known around the net as 120thingsin20years or more often as Bullwinkle II

It's been something I've been promising to do for 5 years or so, but I'm finally building the third incarnation of my boat Bullwinkle III.

I had to study electronics for a bit to sort some of the stuff I'll need to make, but the real reason for the delay is down to procrastination.

The current state of my boat is a pair of hulls on a trailer, with a crate containing 360watts of solar panels, a charge controller, a big deep cycle battery, a trolling motor, and 1.8m square of plywood. I also own a 1.8m square grow house frame and a swivel office chair.

The plan is to cut down the growhouse frame a bit to make it more stable, and mount the solar as it's roof. The office chair will control the existing rudders via some cables and pullies, and the trolling motor will be mounted roughly half way along, and halfway between the hulls. I'll cut the shaft and twist the top 90 degrees so I can use it like a motor bike throttle mounted near my chair.

The ultimate plan is to cruise 2000km along the Murray River, and add things to the boat as required. Things like a solar tracker to point the panels at the sun regardless of where the boats going, a garden etc etc etc

That's it.

So far I've made the tail lights work by replacing the bulbs with LEDs set in epoxy.

I've got quite a bit more to do :)

I'll have my head down for a bit looking at all the posts that will no doubt answer a lot of my existing questions, but I'm going to need some help :)

I'm also willing to help with anything I might have already happened to have filled my brain with so far, so please ask if you think I might know something.

By way of reference, for some reason I couldn't link to my blog in my profile, but a google search of my username might indicate some topics I might be ably to contribute to.

I'm getting pretty good at picking the right forums to join to learn stuff, so you all should think nice things about yourselves. You seem like a decent bunch of humans with a lot to share :)

Thanks in advance :)

Bullwinkle II
 

GT1000000

Rear Admiral
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Jul 13, 2011
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4,916
Welcome aboard, Bull...
Love to see some pics of the first couple of Bullwinkles and get a better idea of what you got planned...
All the best!
 
Joined
Jan 28, 2015
Messages
16
Welcome aboard, Bull...
Love to see some pics of the first couple of Bullwinkles and get a better idea of what you got planned...
All the best!



Thanks for the welcome. :)

I dont have any pics of the first two versions of the boat, and for various reasons I'm forced to be on a windows box for a bit so I cant figure out how to resize a pic to allow me to post it to this forum. (anyone have any idea ?(normally I live in a linux world) )

I'll figure it out and post some pics as I progress. .

I spend a lot of time within forums doing the learning thing I do, and they are all different. Is it an ok thing in this place to have a "project" thread where I post everything all in this one thread, or should I post everything under separate threads with headings that reflect the topic at hand?

eg... if I were about to start working on the solar tracking software/hardware, is it ok to put it within this project thread, or do I need to break it all up and put it in the electronics section?

Personally I enjoy reading about peoples projects all in one place, but I understand the need for the ability to be able to search for topics like... say... "Controlling your trolling motor remotely" or whatever.

So....

Is it cool if I post all this stuff as a "project" thread, or do I need to break it down into each different topic?
 

GA_Boater

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120 - It would be better to keep it all together. Solar tracking or the actual boat are all part of the same project, so in one thread is the best way.

For pic posting, open an account on Photobucket, store your pics and you can easily put the pics in your posts. Copy the IMG code, paste it into your post and a perfectly sized, large pic is transferred into the post. You might not see it until you preview the post.
 
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No Title

120 - It would be better to keep it all together. Solar tracking or the actual boat are all part of the same project, so in one thread is the best way.

For pic posting, open an account on Photobucket, store your pics and you can easily put the pics in your posts. Copy the IMG code, paste it into your post and a perfectly sized, large pic is transferred into the post. You might not see it until you preview the post.

This is how my fine ship looks at the moment. I removed the little 2 stroke, and the decking, and I'm thinking about removing the existing rudders. They run quite deep and I've offset the controller on my trolling motor by 90 degrees and I'm now thinking I should bow mount it and use it for steering as well. The downside/upside to a catamaran is they track really well and dont like turning so much. So having a mid mounted motor and normal rear rudders will give me a poor turning cycle. I hope to spend most of my time fishing in close toward the riverbanks, so being able to turn might be nice. Also the majority of the floatation is forward and centre. The aft hull shape doesnt really need to add a lot to buoyancy with a sail in place, so was never designed to have an overweight middle aged dude fishing from it. With that in mind The decking needs to be moved further forward, almost to the very front. This should allow a length of timber to be attached at the front to mount the motor, but with just enough space to still allow the motor to kick back if it hit's the ground.

The solar frame and panels weigh around 45kg and will be set over the existing trampoline[FONT=arial, sans-serif] and would also serve as some storage space for some camping kit. So perhaps 65kg there, and with battery, motor, decking and some electronics (and my ethanol to fat carbon sequestration program I maintain) that should leave around 120kg up the front. Which means I only need to lose as much weight as my fishing gear and the office chair weighs! I already lost 12kg so I could take the garden. Oh yeah. I didnt mention the garden.[/FONT]

The only downside to the bow mounted motor, is that like all good seafaring folk underway at walking pace on a solar boat, I'll want to dangle my feet in the water. But the motor at the front will put an end to that.

But that brings me to the subject of ducting the prop.

I have so much to learn. Searching the forum now :)
 

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I cant find anything on the forum about ducted props, but as I understand it...

Things like sails and wings and props work by ....

1. creating a difference in high and low pressure on each side of the thing and acting like a wing and generating "lift" in a forward direction

2. shovelling water back behind you really fast like a jet, paddle, or screw (or someone throwing buckets of water behind the boat very quickly)

3. whatever the real thing that's now going on with the high low pressure thing but that I don't understand. (see point 1)

Either way if you look in the sky sometimes, depending on the wealth of your sky, you'll see funny little extra bits stuck on wings. As I understand it, this stops the low pressure we humans took all that trouble of making on top of our wings, mixing with all that high pressure we made under the wings.

When we allow the low and high pressure stuff to mix, it tuns into drag and cavitation, and ugliness, and generally stops being discrete bits of useful high and low pressure.


At least that's how I like to understand it.

It works when making my lures at least.



So if we have a rotating wing like a prop, and we stick one of those extra bits you see sometimes on modern wings, and take it to the extreme, you get one of those toy helicopters with the ring all around the blade, or a ducted prop you sometimes see on things like tug boats. (is this also how a jet boat works?)

So...

Given my boat is only ever going to manage a slow jogging pace at best, will wrapping the prop in a tube of 8 inch PVC help?

It's just a thought.

But It's a thought (like many others) that I don't have a particularly good grasp on.

Is anyone into this stuff?
 
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Can I post links to something like wikipedia posts on tug boats with ducted props?

Your guidelines say "Username, avatar or signature shall not contain business names, website links or personal info. Links to boating related educational material may be allowed"

Is there someone I should check with before posting a link, or do you just delete them if someone posts outside your guidelines?

ie Do I just link and see what happens, or check first?
 

jbcurt00

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Oct 25, 2011
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As long as the info isn't posted at a site that could be considered a competitor of our sponsor, IE: WestSystem (WS) epoxy is sold by James Town Distributors (JTD), and JTD town might have info about it posted on their site, not WestSystems site. If you link the info at JTD instead of directly from WS, the iboats server may redact the name and or website address.

Iboats sells LOTS of stuff, so yes, occasionally posts get auto-redacted. But if you want to post a link to a DIY helpful ducted fan site or how-to, you can.

Here's a concrete countertop how to I'd like to try sometime:
http://www.instructables.com/id/Basic-Concrete-Countertop/

If the server had redacted it, it would look something like this:
http://*********/Basic-Conc********rtop/
 

GA_Boater

Honorary Moderator Emeritus
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The forum has plenty of stuff about ducted props. Every jet drive and jet PWC uses one. But in my opinion, it's overkill for a trolling motor propulsion system. Looking at your pic. I assume you want to sit on the front of the tramp and dangle your tootsies. You need to mount the TM as far forward as possible or she won't steer - then your toes are safe.

Also, the control head doesn't need to remain on the end of the motor shaft. Extend the wiring and put it where you want for ease of control. Steering can be by a single cable when you determine where the TM will be finally located. Check out this TM powered kayak PowerYak on Glen L. The construction steps should give you some ideas. The TM can be front or rear on your cat.
 
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Thanks jbcurt00.


GA_Boater, it hadnt even occurred to me that I could remove the controller from the TM and put it where I want. It will probably only have two wires in the shaft after all. I didnt actually pull it off when I rotated the top so I didnt get to peek.

The majority of the boats boyancy is set forward. ie the backs of the hulls are shallow compared to the front, so the plan was to set some decking forward of the existing trampoline. That would be an uncluttered deck space for fishing from (except for the slight clutter of the motor).

But after looking at the project today, I think I'm going to have to rethink how I mount the solar. The frame I'm thinking of using is going to be too flimsy for the time it's on the tralier I think.
 
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No Title

I built a more sturdy frame to hold the solar panels that sits quite low to the back half of the boat.. On my epic adventure, I'll add 4 extension tubes so that I can get under the frame and use the space (and perhaps even sleep under if), but when I just go out for a day trip, I'll leave the tubes off, and keep it low. It needs to be low so it can travel on highways on the trailer without shaking to bits, or catching too much wind.

With the extension tubes installed, I can sit under it on my adapted (hacksaw) office chair. Without the extension tubes I'm be restricted to the 1.8m square marine play deck in front. Plenty of room for two to throw lures around.

The panels will fit within the largest rectangle of the frame on each side.

2X 180 watt 24v
 

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If I have some decent thick wires running to a load, but they go into a watt metre with thinner wires for a few inches, what happens?

Is it a case of the thinnest bit of wire sets the amount of loss for the total length of wire? Or does going immediately back to thicker wire mean my losses are minimal? The load (trolling motor) came with thick wires, so I'm guessing their thickness is required, but the watt meter has wires less than half the diameter.
 
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I connected up a watt metre to my motor and battery and confirmed for the first time that my solar system should run the motor at full power (given full sun) all day)

Yay!

This project has been years in the planning, and I've never known what the motor draws because my multimetre only goes to 10 amps.

I have 360W of solar, and the trolling motor uses about that on full power, so if I use speed 4 of 5, I should be able to cruise all day at a fast walk, and top up the batteries so they are full each night for safety/lighting/phone/internet etc etc.

This should also give me a bit of reserve so I can find a camp site if I find myself with a big headwind or whatever. Wind is the killer on my little underpowered boat. More often than not, I should be able to dodge it a bit by sticking to one side of the river or the other.

It's going to work!

I got an offer of help from the owner of a local eBike store called MiCycles yesterday. He had the pleasure of driving a solar car across the finish line a few years back (Darwin to Adelaide solar race) so all electrical, solar, and battery help will now be only a phone call away.

Awesome.

It's going to work! :)

Today I think I discovered my 10 year old deep cycle lead acid battery is a bit past it which is a little sad.

It's also a little sad that yesterday I told the dude from the eBike store that I didn't want corporate sponsorship because I was just some guy going fishing and didnt want a call from head office every time the time-lapse camera caught me scratching my butt.

Perhaps I should have checked my battery first :)

ITS GOING TO WORK!

Happy :)
 
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