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Mini Vee Race Boat Plans
Page Eight
Turn Over, Flotation, Carlins

Turn Over

Turn over your hull and stabilize it on the sawhorses, or whatever work surface you are using.

Carlins

The carlins are the stringers located where the deck meets the coaming. Install these now.

Sealing the interior

The interior surfaces can be sealed with epoxy or paint. I used paint (latex flat, three coats) in most of the hull, but used epoxy in most of the cockpit, with particular emphasis on the area behind bulkhead #4 where water is most likely to gather and may even sit for a time.

Keep paint and epoxy off surfaces where the deck will be glued down.

Flotation

APBA rules require at least two cubic feet of flotation for a GT Pro boat. One cubic foot will support ~60 lbs., so two cubic feet is good for 120 lbs. That is about what a 31.8 cu. in. OMC motor weighs. But you will also have a battery, trim pump and cylinder, and perhaps ballast to meet minumum weight. (I carry about 20 lbs. of ballast.)

On the other hand, the boat itself is bouyant, and the gas tank is apt to have some airspace in it.

But, I'd still say three cubic feet minimum for a GT Pro race boat.

Filling most of the under-deck space from bulkheads two through four should be plenty. But leave some space next to the coaming for running wires and control cables. I installed permanent barriers in my boat, then, after the deck was installed, turned the boat on its gunwale and poured foam through a hole in the coaming and the hole in the barrier. Then rolled it up onto its other gunwale and repeated.

HOWEVER

I now have slightly concave decks between bulkheads two and three. My belief is, after the foam finished expanding, it shrunk back a bit, and pulled the deck down with it. Luckily, it didn't distort the bottom very much. Similar effects have shown up on my Sport C boat.

For the Dillon Pro Vee, I lined the space with poly....

... and then screwed down a cover of hardboad (plywood, or any board product will do). Be sure to line the underside of the cover board with poly. One or more holes in the cover serve to pour the foam.

BEFORE PROCEDING, SEAL WITH EPOXY ALL PLYWOOD SURFACES THAT WILL BE INACCESSABLE AFTER THE FOAM IS POURED.

Mix and pour the foam as the directions on the product instruct. You will get best foaming action if the chemicals are warm : 70 degrees F or so ideally.

The foam may still end up slightly higher than the bulkheads and/or longitudinal framing. The simplest solution is to sand it down with a belt or disc sander. It goes very quickly, but is a bit messy -- keep your shop vac handy.

I found the bottom between bulkhead four and the transom to be a bit too flexible, especially considering that this is the part of the boat that will be banging against the waves and generally taking the punishment. So I added the reinforcement shown. Any piece of plywood, at least a few inches wide, will do. Or perhaps a piece of lumber two to three inches wide.

Remember to cut limbers so that this brace does not become a water trap.

The original Mini Vee, built in 2006 using 1/4" AC plywood, never gave me any trouble. The Mini Vee I built in 2009, using 5mm luan plywood, did turn out to be vulnerable in this area however.

My recommendation, especially if you use 5mm luan plywood, is to use two or even three braces such as the one shown at right, or consider adding a second layer of plywood before installing the single brace shown.

I personally plan to double the plywood in the next Mini Vees I build (two boats are planned for winter 2010).

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