Electric dink options for your Catamaran

[BigBeakie]

Originally Posted by 44'cruisingcat

No need to use stainless tube, the Magic carpet and another dinghy of Bob Oram's design have simply glassed in heavy wall conduit to slot the axles into. Axles are pulltruded solid glass rod.

Another idea is to fit short sections of this tubing vertically into the coamings fore and aft, which gives a place to store the wheels when not in use and also lets the wheels serve as rolling fenders on the dinghy. This also greatly reduces one of the concerns of hard dinghies, that of them bumping boats when coming alongside.

Nice! Thanks for that. Easier and cheaper.

[tp12]

BB, did you consider the ripple tenders from Spirited?

https://spiriteddesigns.com.au/inc/s...tender/436/784

[BigBeakie]

Yes we did consider the Ripple seriously, but elected to go with hulls & NACRA rudder designed for sailing, that could also have a transom for an outboard or EP with solar panel bimini.

[sailhand]

The ripple tenders have a fairly veed hull and no rocker i think. Im not sure they would be as suitable for sailing. My hulls have rocker and it definitely tested better. I actually built and tested 7 different hull shapes 3.5 metres long and tested them all with a 3 a 5 and an 8 hp. One up and two up with the same two people, ok i confess i didnt weigh myself before each run but i did run in both directions and average for wind and tide. I really do need serious psychological help.
These hull shapes were all developed over a 3 year period on computer with various software packages. 4 had rocker and the rest didnt The current hulls were by far the best and the worst were round bilge hulls with a slightly lower prismatic coefficient. Think your average off the beach cat. I was at the a class worlds a couple of weeks ago and it was interesting to see the fastest hull shapes. If you took say a nacra 5.2 of old unbolted the hulls and bolted them back on upside down you would be a lot closer in hull shape to the current speed machines than the original 5.2s. I guess you could say that the a class cat world really has been turned on its head. Its one thing to imagine the perfect hullshape on something that is sitting still, its a completely different ballgame when you look at hydrodynamic lift and wetted surface area and its effect on drag at various speeds and displacements. Anyway im confident that i dont have the ability to improve on my design, im sure other people could i f they had nothing better to waste their lives on. I still have dinghyitis disease however ive decided to reinvent the caravan instead with a monocoque composite van without a chassis so i guess its here we go again. I can actually sense the admirals eyes rolling in her head as i type this. I'm beginning to think theres a chance, just a tiny one, that i might be a little OCD.
Nah that couldn't be right could it.

[BigBeakie]

Sailhand,

I wonder if you can recommend a more efficacious treatment for dinghyitis than building that many hulls? I find myself musing about all sorts of dinghy fantasies, like putting a viewing plate in the hull bottom to see the crayfish as we drift along over the coral, and making a cover that can attach to the sides so the dinghy could be a life raft, and other bizarre dinghyitis type symptoms......

Help!


Sent from my iPad using Cruisers Sailing Forum

[tp12]

Originally Posted by BigBeakie

Sailhand,

I wonder if you can recommend a more efficacious treatment for dinghyitis than building that many hulls? I find myself musing about all sorts of dinghy fantasies, like putting a viewing plate in the hull bottom to see the crayfish as we drift along over the coral, and making a cover that can attach to the sides so the dinghy could be a life raft, and other bizarre dinghyitis type symptoms......

Help!


Sent from my iPad using Cruisers Sailing Forum

You've got it bad! Hahaha.

All good ideas, though. Sounds like you'll need to upgrade to 'Swiss Army Davit's' [emoji23]

[sailhand]

The cure is somewhat elusive, as I write this I am sitting next to angkor wat in cambodia yet writing about dinghys. I think once you suffer from the boating ailment in general there is no cure, Im afraid my friends its terminal. Funny you should mention those two things, I have a pop up two man tent that goes in the dinghy as shelter, not the best solution in say stormy conditions but fine the rest of the time. I figured fold it up and put it away securely lashed and weather the storm then put it back up, there's issues with exposure so maybe a stronger two thirds size tougher canopy is worth a thought mounted on track near the gunwhale.
Best solution dont lose the big boat which basically means dont set it on fire and carry good fire extinguishers in the right places. Its not gonna sink check out pictures of the Oram cat that tore the bottom of both hulls out. They drove it many miles to the slipway with the outboards. Come to think of it thats another good argument for outboards over diesels. I have twin diesel shaft drives.
As for the viewing window i think its a great idea, you need shade over the top though. I have been pondering that for years and the best solution i could come up with was a depth sounder and transducer mounted on a removable box which contains a small battery and a solar panel. I used a humminbird helix side imaging sounder with gold card navionics in it. Great for finding navigable channels and good anchorages for the mothership. Also very handy for finding fish. Transducer mounts on half a transom bracket off a dead 3hp yamaha so just clamp it on and take it off again as required. Whole set up is self contained and very light. As i am self draining i have no access into the hulls not even a bung at this stage. I have a large deck area over each hull that was decored during the build for hatches however i never put them in. Preferred to keep the whole thing watertight as long as possible. The best way for me to do the viewing port is to put a hole in the bridgedeck and use a bathiscope, food for thought. Or else I could just toddle over to some ancient ruins and marvel at the engineering efforts of an ancient civilisation. Nah back to the viewing port what if.......