Mini-Brig Project: Hull Construction - Step 11

Hull Construction: Step 11

Finishing / Constructing the Mid/Bow Seat:

Step 1: Fill the Seat With Foam/Positive Flotation:

At this point, you'll want to add some positive flotation under the mid/bow seat. This will add a nice safety feature in the unlikely event she should capsize or get swamped. There are several methods to accomplish this. One method is to use "liquid foam" that hardens once it is poured in the seat. This usually comes in two parts, or in a spray can. It is expensive to buy the "expanding foam" in cans for a job this size, it is best to make a visit to your local industrial plastics shop.

Using liquid/expanding foam  is the preferred method, but costs quite a bit of money. In our case, since we were on a budget we settled on "Foam Chips" that is to break up a bunch of foam from various electronics products into medium sized pieces that are tightly packed. You could then top this with the liquid expanding foam or glue. It is easy to find foam pieces from large retailers such as Staples, Home Depot, Office Depot etc.. 

Otherwise, you could buy foam peanuts, or the shipping style "air bags" which can be packed under the seat.


Midseat flotation

A picture of the mid seat with foam chips installed. 
(click to enlarge)


Step 2: Cutting and Mounting The Mid/Bow Seat:

The Mid/Bow Seat is cut in two pieces, you will need to place 2" x 2" blocks about 3" in length inside the frame for the seat to attach to. This will give it good structural integrity and is easier than trying to screw into plywood. Note: see the block in the above photo, you should have several of these in place about 6-8 inches apart.

You can finish these blocks with a light coat of shellac or varnish to keep them from rotting/weathering if you wish. However, the seat should be mounted fairly tightly so that no water is able to get in.

The seat extends past the front of the daggerboard trunk, this will serve as a seat for a crew person / gunner. The Daggerboard sits recessed in the trunk, so a boat cushion can be placed on top of the daggerboard, as the trunk also doubles as a seat.

A couple of small 1/2" x 1" legs are attached to 2" x 2" blocks on the underside of the seat, and serve as "legs" to provide added support. These are epoxied in place to the inside of the hull. Brass screws are used to hold the seat in place with the frame screwing it into the mounting blocks, and any gaps are filled by caulking and/or wood putty. This is best done by turning the boat upside down, and then looking along the seam.

A picture of the finished mid/bow seat installed. 
(click to enlarge)

Step 3: Install the rear seat

You will also want to install the rear (captain's) seat in the same fashion. We used 2x2" blocks to help anchor the seat to the sides of the brig and sealed it with Lepages "Bulldog" grip pl premium adhesive. This seat could have also haven been fitted with a hinged lid and possibly used for storage (see pictures of Liberte). We didn't try this option on the Adventure.

Varnish rear seat Adventure

Painting and Installing the rear seat is child's play (This is my 3 1/2 year old daughter Kaylin)

The Liberte has a sectioned rear seat, with the middle set for flotation and storage lockers on both port and starboard.


The rear seat in the Liberte is separated into compartments, with the middle containing positive floatation and the sides, with hinged lids that provide a storage lockee.Once everything has been "dry fitted" and glued together, you will need to seal the wood by liberally applying epoxy.

Also, if the boat is going to be seeing any kind of weather or stored outside, the chambers could fill with water. It is adviseable to drill a small "breather" hole that can be corked or plugged so that the chamber can dry out should it become water logged.

In Liberte, there is a small 1 /34" PVC pipe that is drilled into the centre chamber about 1" up from the bottom of the boat. it can be plugged with a wood cork fit to size, or a PVC cap. The purpose is to allow rain, and bildge water the ability to drain out of the locker. and provide ventillation so that the chamber can dry out in better weather.