Harmonica Part 5  
By Bill Nolen - Oklahoma City, Oklahoma - USA

A Micro-Shanty Style Houseboat as built by Bill Nolen

Part 1 - Part 2 - Part 3 - Part 4 - Part 5 - Part 6 - Part 7

After all my hired hands had collected their money and fled the scene I pushed the boat back into its barn. My, the boat sure looks different with the bottom resting in its proper position! For the first time I was able to envision this square plywood box actually being a boat!

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Looking aft

First order of business was to apply PL Polyurethane Concrete & Masonry Sealer in all the seams on the insides of the boat's hull. PL Concrete Sealer comes out of the tube in a very heavy mixture, but was easy to press into any gaps in the seams using a wooden stick or plastic spoon.

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PL concrete sealer

I had read that PL Concrete Sealer would bubble up as it cured, however this did not happen to any of the seams on my boat. The mixture cured to a rubber like texture, that I believe, will remain flexible.

The plans for the Harmonica call for a flat roof that has an open slot in the center of the roof. This open slot is commonly called a "bird watchers roof" and in my opinion is a very desirable feature of this boat. However, I have never been an admirer of the flat roof!

Besides, in the back of my one-cell brain, I had been thinking that an old style Gypsy paint job and décor would sure look nice, but the flat roof would have to go! So, I cut out some 2" by 4" spacers and placed then on the roofline to see how a rounded roof would look like.

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Flat roof

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Rounded roof

Well, what do you think? I decided that I liked the rounded look much better! Plus, the rounded roof gives slightly more headroom to any sitting passenger. I applied a bunch of PL Polyurethane Premium Construction Adhesive to the top of the bulkheads, and using clamps attached the wooden spacers to the bulkheads.

I then turned my attention to the seats/bunks of the center cabin area. The Harmonica plans show that the 2" by 6" hull stiffeners are used for the bottom of the seats/bunks, thus the seats/bunks height would only be 6" from the cabin floor. After doing quite a bit of measurement, and consulting with people who had built Harmonica boats, I decided that I would be able to raise the seat/bunk height to 14" and still have sufficient headroom with the round roof.

Ripping some 1/4" plywood sheets into 14" panels, I measured and cut two of these panels into 6' 6" lengths. Laying the panels on the cabin floor I measured the locations of the 1" by 4" cross braces and the notches needed to clear the 2" by 2" bulkhead boards. To cut the curving surface of the hull's floor on the plywood panels, I dug around in my wood scrap pile and found the discarded bow ends of the 2" by 6" stiffeners and used one for a guide.

I then cut the panels to fit the floor and bulkheads. After assuring that the panels would fit, I then cut and attached, using Titebond lll glue, 1" by 2" boards to reinforce the panels. At the top of the panels I moved the reinforce board down 1/4" to allow space for the top plywood top or lid to fit after the panels are installed.

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Bunk sides completed

Prior to installing the seat panels I discovered that one of the modifications that I had hoped to make wasn't going to work! I had modified bulkhead #2 by cutting two side opening instead of the center opening as set forth in Jim Michalak's Harmonica plans. I had thought that by extending the bunk area into the bow storage area I would be able to use about 18" in the center of the boat for an area for a Porta-potty and cooking cabinet. However, by raising the bunk height to 14" instead of 6", there just wasn't going to be enough room for my feet to slide into the storage area! So I had to remove the plywood web in the center of the bulkhead and install two 2" by 2" braces. After the glue on these braces had cured I was ready to install the bunk panels.

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Center ply removed

To determine the seat width that would provide some comfort and still leave room in the center aisle I moved the seat side panels around until I found a location that would give me a seat width of 21" and be fairly easy to attach to the bulkheads and stiffeners. If a person was planning on spending many nights sleeping on the Harmonica, the width of the seats could be increased by several inches and still have sufficient room in the aisle.

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Seat assembly 1

This location required that I insert spacers between the seat panels and the hull stiffeners.

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Seat assembly 2

After I was happy with the location of the seat panels, I apply PL Adhesives to the panel surfaces and clamped the two panels into place.

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Seat assembly 3

I then cut 2" by 2" boards to fit on the hull sides across from the two panels. These boards will provide a surface for the seat tops to rest upon. To attach the boards, I first marked their proper location on the boat's hull, and then drilled 1/8" holes from the insides of the hull. Later I applied a heavy bead of PL Adhesive to the boards and held them in place while my son applied wood screws from the outside of the hull. These screws will be removed after the adhesive cures.

After the adhesive cured I cut small plywood tabs and glued the tabs to the bottom of the 2" by 2" boards and the seat panels. These tabs will align and support the seat cross braces while the glue cures.

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Seat assembly 4

Using 1" by 2" stock boards I cut and installed cross braces by gluing and clamping the boards to the small tabs, thereby adding braces to support the two seat panel tops.

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Seat tops installed

Since I could not use the center area of the boat for the Porta-potty and stove, I elected to add a cabinet to the aft end of the Harmonica to house these items. However, first I had to decide on which side of the boat did I want to place the operator's seat. After much pondering on the choice I finally decided that I would place the operator's seat on the starboard side and the Porta-potty and stove cabinet on the port side. Using scrap boards and plywood I first made the Operator's seat enclosure, and then the framework for the port cabinet that will provide a surface for the single burner stove, and a enclosed cabinet area to contain the Porta-Potty.

To make the use of the Porta-Potty easier I made the cabinet top over the Porta-Potty swing upward where a simple latch holds it in place. I also made the door to the Porta-Potty enclosure swing open towards the bow of the boat. With a small curtain sliding from the starboard side, a small measure of privacy might be attained. To add a neat look to the cabinet raising and swinging doors I searched our local Lowe's and Home Depot for just the right looking hinges, but failed to find anything I liked. Looking through the Duckworks Boat Builders Supply's Web Catalog I found just the right hinges for my Harmonica's doors! White Nylon Door Hinges, PN: SD-202531, which was a real bargain for only $1.78 each.

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Operator's seat

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Porta-Potty area

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Porta-Potty cabinet 1

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Porta-potty cabinet hinges

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Aft end of cabin

Having the rough-in work finished on the port cabinet, I turned my attention to the bow area of the Harmonica. Okay, so I do have a limited attention span problem! Once I get tired working on one area I've found it best if I work elsewhere for a while! My quality of workmanship doesn't improve, but I feel so much better!

I used two 2" by 4" boards, rounded on the edges, for the bow upright boards. Other Harmonica builders had advised me that since the bow uprights are bolted on the insides of the bow transom it would be wise to attach these boards before the bow deck sheeting was attached. Thereby reducing the need for me to force my pudgy body into the bow storage space! I used three 1/4" bolts to attach the boards to the framework of the bow transom.

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Bow upright boards

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Bow upright bolts

Deciding that the boat's bow eyebolt should also be installed prior to the deck sheeting, I attached, with glue and wood screws, a long 2" by 4" board bracing along the insides of the bow transom. I then drilled the hole for the front eyebolt. I used large fender washers on the inside 2" by 4" brace to provide addition holding strength to the eyebolt.

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I decided not to install the deck sheeting until I installed the foam flotation in the bow storage area. Since the foam blocks were stored elsewhere, and it was raining, I started cutting the window openings in the boat's side panels. Using the plastic sheets that I had bought at Lowe's as a guide, I marked the outline of the sheets, then I measured 3/8" inside the guide lines, marked that area, and then drilled holes in each corner of the new lines. I used a jigsaw to cut the window openings.

Prior to this time I had considered several ways to construct the windows. My first thought was to buy used RV trailer windows and install them. However, I quickly learned that securing the right size of windows was difficult, and frankly, the cost of $30 to $40 per window, plus crating and shipping costs, was way too costly for my billfold!

I then discussed, with other boat builders, the various methods of making sliding opening windows, windows that opened upward, and fixed in place non-opening windows. I finally decided that fixed non-opening windows, while certainly not my first choice, would be OK for my boat since the bird-watcher style roof should provide sufficient ventilation in the cabin area.

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Front Side window

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Front Side window framed

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Front two windows framed

The windows are framed with 1" by 2" boards in such a manner so that the 1/4" plywood boat sides provide a surface for the plastic window sheet to fit against, and hopefully provide a watertight seal. More details later when I install the plastic sheets and internal window frames.

In the next part of this long-winded-drawn-out article, I will be installing the foam flotation blocks, completing the painting (well, most of the painting anyway!) and who knows…maybe even install the rounded roof panels, and give the hull it's first taste of lake water?

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Wrapped foam block