modified malahini

[DrBryanJ]

I have been studying the plans for the malahini and am getting ready to build. I intend to add a 17 degree deadrise.

The advantage is:

I believe this will soften the ride a bit.
It also allows me to add 2 2X4 longitudinals (correct term?) which I can bolt the transom plywood
It will give me some storage under the floor for anchor, tow rope, oar and possibly skis.

The disadvantage is:

Untested hull
Increased drag
More power needed to get on plane.

I am in the process of redrawing the frame plans.

Anyone have any comments or recommendations?

[fergal butler]

I think it might be easier to look at a different boat than to try and modify one, I'm not a naval architect by any means so have no idea whats involved but I get the feeling that once you change one thing you will end up changing ten things.
Just my two cent

[Iggy]

I'm with Fergal on this one. I'm no naval architect, but I would suspect that the hull properties change a lot based on the lower hull shape.

If the size and deck layout is what attracts you to a Malahini, but you'd like to have more V to the hull for choppy water conditions, I'd look for a V hull and dress up the deck instead.

If I am reading it properly, the Geronimo is the same size but has a V hull over the Malahini.

https://www.boatdesigns.com/16-Geronimo ... ducts/325/

You could probably round the transom and frame 1 slightly on a Genonimo to give it some of the Malahini's curves. Probably a lower risk to modify what's above the water than what's in direct contact with the water on a hull design.

[DrBryanJ]

That is a good idea. At least I'll order plans and see what can be done. Thanks

[DrBryanJ]

I ordered plans for a roustabout and will see if it can be made to look more like a malahini.

[Iggy]

Rusabout's a solid choice, nice length, wide beam, excellent hull for choppy water (vs Malahini).



It has its own lines, no curved rear end but still looks great in a natural wood finish.

It will really come down to how you finish the top deck, the planking layout.

Good choice.

[Bill Edmundson]

Wow! Have not seen this boat with the extended hull! I think that is a nice option for rougher water.

Bill

[DrBryanJ]

Looked at many boat designs. Decided to take the hull bottom from a donzi 16 and the upper part from the Malahini. Fits together nicely. Donzi plans are very basic as far as internal structures to make hull sound. Will use roustabout plans for internal parts especially transom (both say up to 135hp) as they seem similar to donzi 16.

Started cutting templates for frames out of 1/4 hardboard, which I will use to cut pieces with router. Glad I decided to go this route because I already made several mistakes. Don't mind wasting a 1 dollar piece of hardboard instead of a 30 dollar piece of hardwood.

Cost for boat went up substantially: Had to trade a new fence for the backyard ($3000) and a new stainless steel refrigerator ($2000) for the boat.


Bryan

[jprice]

Just curious, do you have a donzi hull that you're chopping the top off of? Or do you have some donzi plans?

[DrBryanJ]

I have donzi plans. They give you shapes for the frames, but nothing about assembly.

[jprice]

Interesting. Didn't know you could get plans for a name brand like that.

Looking forward to seeing pics of this one.

[DrBryanJ]

After many hours of drawing and calculating and redrawing, I have all my frame templates complete. Started cutting stem pieces today from 3/4 df marine ply.

Plan on picking up mahogany on Monday for rest of frames.
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[DrBryanJ]

I would like to cut the transom braces. The plans call the transom angle @ 12 degrees. It seems the consensus is a 17 degree angle works better for todays outboards. Am I correct or did I miss understand something?

[Bill Edmundson]

Go to a boat dealer that sells the brand and size of outboard you want to use. They can copy a manual page from the shop manual that shows the best angle.

Bill

[DrBryanJ]

Thanks Bill. You always have good answers.