All hands on deck...

The time has finally come to re-deck  PT-305. The sheer is in place, deck ribs are secure, the inner layer of planking laid, the covering boards are installed and some the ridiculous eighty foot deck boards are ready for installation. Smiles are all around as the crew, for the first time, learns how to deck a Higgins PT boat. 

The groundwork for this moment was laid down back in 2009 when it was discovered that the deck of PT-305, and the ribs that supported it, were completely shot. Over sixty years of wear and tear had taken their toll on the construction. Deck ribs failed, screws corroded and planks rotted. This resulted in a very dangerous situation- any careless footstep on the deck would send a volunteer foot right through. Luckily the caution and vigilance of the crew has prevented any serious deck related mishap. The other major problem with the deterioration of the deck is structural. The planking of a wooden boat provides the majority of the strength in the completed vessel. A weak top deck would undermine the structural integrity of the boat while underway; therefore, if the deck was determined to be weak it would have to go. The crew’s worst fears were confirmed when the deck was removed.  Hoping the ribs would still be intact and could be used, the deck was cut away around the ribs, only to reveal that the glue in the deck ribs had failed and the ribs had delaminated, effectively flattening the deck and rendering it structurally unsound. The ribs were removed and the process of replacing the deck began.

This 2008 photo of a deck rib and decking demonstrates the damage done to the original woodwork.

Many measurements had to be made, sections of hull restored, debates started and material ordered before the deck was laid again. This is why it took until this Saturday to begin laying the final layer of decking.

Over the last few weeks the inner layer of 3/” mahogany planking was laid in a diagonal pattern across the entire length of the deck. This inner layer rests directly on the deck ribs, meaning when you are inside of the boat this is the “roof”. While the inner layer was being laid, the covering board was completed and Doc began production of the top layer of deck boards. The top deck boards are 5/8” by 2 inch mahogany planks that are spliced together to create boards up to 80 feet long. The deck boards run fore to aft, the entire length of the boat, except for the center section that is interrupted by the chart house and engine room hatch. Each deck board has a rabbet cut in it on both sides for the full length. A rabbet is a groove cut in boards to accept and overlap other boards forming a tight seal or, in this case, it forms a groove between neighboring boards that will accept caulking.

Due to the length of the deck boards, the crew has to route them using a special setup outside in order to create the rabbets. 

This photo shows detail of the decking.  The holes will get screws, and rivets will go on either side of the line of screws.  Caulking will fill the crevices in-between each deck plank.  The center plank, wider than the, others is known as the “king plank.” 

Screwing down the deck planks is a multi-person job.  The planks have to be perfectly aligned, and screwed into deck ribs which are not visible beneath the inner planking. 

The completed deck will be one inch thick consisting of the inner 3/8” planking, one layer of dolfinite, one layer of canvas, another layer of dolfinite and the final top layer of 5/8” deck boards. The rabbets in the final deck boards will allow caulking between boards. This entire assembly is screwed to every deck rib and riveted together between every deck rib. Because we are just learning how to do this and there is not a war on that needs this boat, we are taking a slower approach to decking the boat. The entire deck will be put on dry, without the dolfinite layers and canvas. Once the entire deck is fitted and “installed” it will be removed by section and “finished” installed with the canvas and dolfinite.

 This is a good time to explain the wonderful substance that is dolfinite. Dolfinite is a bedding compound used to waterproof joining layers of wood. It has many other uses, but in the case of PT-305, waterproofing is its main function. You can’t let the happy little dolphin on the front of the can lure you into a false sense of happiness. Its color is a mix of olive drab and puke green, and it has a smell of its own and a mind of its own. That happy little dolphin mocks you as this paste like substance sticks to anything and everything. It has single handedly ruined clothes and tools for Higgins boat volunteers since 1997. “Dolfinite duty” is a dreaded volunteer assignment that is greeted with laughter and stories of what this substance has done to hair, clothes, emotions and tools. Plain and simple, it isn't fun to work with, but for some reason we always enjoy it. After 60 years some of the original dolfinite is still moist, so this stuff works very well. When all is said and done we will have re-applied 200 gallons of dolfinite to PT-305. This accounts for roughly 3,600 pounds of the finished weight of the boat.

Volunteers Harold and Ed prepare to work with dolfinite. 

In this photo you can see dolfinite spread on top of canvas on a piece awaiting installation. 

In other areas, work continues at a fast pace. Frank’s crew working in the forepeak has completed the installation of all side and lower hull ribs and the stairs leading into the rope locker in the forepeak. Work on the bow should be completed in the next few weeks.

Frank and crew can be seen on the right-hand side of  this photo, hard at work on the bow of PT-305. 

The engine crew under Randy have one Packard 4M-2500 engine ready to go. The engine looks beautiful in the Packard colors matched from paint on original parts. Jim and Randy are working on mounting water pumps to the engines and finalizing plans for the test stand. One of the current engine stands will be converted to an engine test stand that will be able to sustain one idling engine for a few hours. Because of space restrictions within the engine room, Randy wants the engines thoroughly tested before they are installed. This will make quite a show in the parking lot next to the warehouse.

Propeller shaft alignment was momentarily discussed in the last post, and this week the tedious process continued. Because the engines and shaft need to be in almost perfect alignment this process will take a while. One of the oldest shipyard methods for aligning a shaft and support struts is the method that the crew has used on the two landing craft we have restored, and is now being used on PT-305. First, the angle of the shaft is determined. The starting and ending positions, the front of the engine and the propeller are established. Connecting these two points are a length of piano wire with a large weight attached to one end. This creates a perfect line, establishing a visual marker for all of the support struts, shaft holes and engine mounts to be measured off of. The support struts have round holes that the propeller shaft passes through. By mounting these struts with the piano wire centered in the middle of the shaft hole, a support system that will hold the shaft along this line is established, thereby creating a straight propeller shaft. This process is not as easy as it seems. It is very difficult to determine the starting and ending positions of the wire, the angle of the propeller shaft you want and centering the wire within the shaft struts. There is also one major catch, being a wooden boat, as soon as PT-305 is placed in the water the shape of the hull will change. The goal is to get it as close as possible in the warehouse to reduce the amount of tweaking required while the boat is in the water.   

Frank, Joey and Norman at work with their propeller shaft alignment setup.  The shaft will pass above the keel (the board in the center) and run through the aft bulkhead of the engine room, eventually passing through the keel and out of the boat. 

Post by Josh Schick and Kali Martin. 

All photos copyright of Jane Swaffield and Kali Martin.