Wednesday, April 23, 2008

Fitting teak deck panels coamings and covering boards

We've been working hard all of last week , thru the weekend, and the first part of this week trying to get this project done so the owner could take his new 60' Hatteras sportfishing yacht to the islands for the Bahamas billfish tournament this weekend. In this first picture we have glued down more of the deck panels.Each panel has been built exactly to the width required to fit between hinges and hatch edges.We start gluing in the center and then work out towards both sides.

While we have been gluing the deck panels we have also milled out the material for the coamings.These coamings are functional as well as beautiful. When the fisherman is working in the cockpit landing or releasing a fish, he can wedge his knees under the bottom and lock himself in freeing both hands for use.

In this photo you can see two pieces of bullnose margins for the steps from the cockpit up to the cabin door. Also visible are the routers we used to rabbet out the backside.It's easier and faster to have lots of routers set up with the various required bits rather than changing bits for the many cuts needed.

Layed out and ready to start making noise, dust,and pretty parts.

After the noise and dust here are the rough parts ready to be fit on site and radiused and sanded.

Here we have glued on the first side covering board.We have to shape blocks for clamping down the outboard edge and clamp these blocks in to keep them from rolling up.

Before we started gluing on the covering boards we had to fit in the corner pieces.These are cut with a very slight taper and sanded to fit.Very time consuming, several hours for each.After the corners are fit we sand the top edge of the coaming with a long hard block to ensure a tight fit between the coaming and the covering board. Later we will shape this corner piece to flow into the coamings and the covering boards.

This is a view of the forward end of the port side coaming.This new Hatteras yacht has an extra kink in the coaming.Just a little something extra to make it more of a challenge.

This shot sows the margins for the mezzanine.The bullnose pieces are milled out of 12/4 teak lumber.

We're closing in now. We have glued and clamped the aft covering board to the boat. We still have to cut across the board in two places for the tuna door but we prefer to do this after the board is epoxied down securely.Several years ago we cut one before we glued it down and just as we finished the first cut the board exploded and within 3 minutes had split several times from end to end , a lot of expensive trash.We had used wider strakes to make up the board and when we disturbed the equilibrium the stress in the laminate just shredded the fibers of the teak.Part of the learning process.

the picture below shows the decking almost completed on the mezzanine.

Here we have installed all of the teak decking and the covering boards and coamings. The tuna door has been cut and rehinged. we still have some detailing to do .The tuna door hinge is not correct and we will have to build and polish a new one.But right now we are off the boat while the owner takes his boat back to play with.We will have to wait several weeks until they return from the Bahamas to complete the final touches.

Sunday, April 13, 2008

Laminated coaming and aft margin

Here we have pulled the coaming off the mold and it's laying next to the cover board. Both of these pieces stll need lots of shaping before being attached to the boat. On the right is a stack of deck panels ready to fit and install on the same boat. These panels are fabricated to fit exactly between the edges of the hatches and the hinges. We do this by adjusting the width of the indavidual planks. your eye won't see this and it eliminates extra seams and cuts in the finished deck. This is the aft margin board for the deck.This has also been resawn and then laminated back together on the same mold to match the cover board and coaming. It's subtle but when it is all completed ties everything together very nicely. Next week we will continue installing deck panels and glue on the coamings.

Saturday, April 12, 2008

Teak decks being installed and curved covering boards get laminated

Alright, here is the aft cover board and it came out very well. The glue lines
are virtually invisible and it looks like we found a bent log to mill this board out of.

These are the first two deck panels installed with epoxy in the cockpit. You can see the bags of lead shot we use to hold them down while the glue dries.Also in this shot are a couple of other tricks which make sure everything stays in the right place. On the forward margin(border) you can see small pieces of wood (tongue depressors) that are glued on with super glue. We put the glue on the small piece of wood , Then spray the accelerator on the teak and then press the little piece to the teak, hold it a second or so and it will hold temporarily but pop off with a chisel and just break thru the glue line without damaging the teak. The little blocks along the sides of the panels are attached in the same manner.

Now we are forming the aft coaming on the same molds we used for the cover board.This board is 2" thick and would take a ferocious amount of pressure to clamp into the required curve. We resaw a 5/8" slice off the back side and then laminate them back together on the mold. We only slice the one piece off because we need to keep this glue line under the cover board far enough to stay out of sight.This junction of cover board and coaming will get a large radius and and we don't want to go thru the glue line on a bias because then the glue line would be quite noticeable.

Wednesday, April 9, 2008

Teak cockpit for a new Hatteras sportfishing yacht.

One of the mainstays of our business is installing teak decks and covering boards on high end sportfishing yachts. Here in Jupiter we are close by many custom builders and also are a destination/jumping off location for boats coming down from the north for the winter.

Currently we are fabricating and installing a teak deck and covering board/coaming for a new 60' Hatteras sportfisher.We have developed a style of covering board/coaming that we call the Palm Beach style. Traditionally very wide teak boards are used for covering boards.These boards are very expensive and are only available with lots of flat grain in the board. Flat grain boards are inherently unstable and very prone to checks and splits, especially around penetrations such as rod holders and hawse pipes.This is sometimes dealt with by fiberglassing the bottom side of the covering board before it is installed. Our belief is that we are epoxying the teak to a fiberglass panel on the boat . A teak to fiberglass epoxy glue joint is a teak to fiberglass epoxy glue joint.

Hatteras sportfishers have a very pronounced sheer in both the vertical and fore and aft directions. We have a technique that was developed specifically to address both the large curvature and to minimize checks and splits. We purchase rough slabs of teak that are from the center of plain sawn logs that are very straight grained and as clear from all natural irregularities as possible. Then we resaw the boards to bookmatch them and then resaw them in the other direction to a width appropriate for the curve of the transom.

The first step is to make accurate templates of the shapes required. This helps us pick out boards that we can use and avoid knots, lightning marks, bug holes and other blemishes.

Then its off to the lumber dealer to sort through piles of teak slabs looking for just the right ones for this project.This is fun because you see many beautiful boards, yet a bit stressful because these boards are pricey and they all have the potential to have bad surprises inside

Once we have the boards and have laid them out its time for cutting. Our shops primary large band saw is this Italian Centauro 800.It has a 5hp motor and it is so far the smoothest cutting band saw I've ever used. It looks like many similar sheet metal saws but is almost a ton of cast iron. The controls are easy and the guides are tough to get aligned just right but every time we shut it down we are saying ,wow what a great saw.

Here we have assembled our bending knees according to the templates plus just a little bit more for spring back.Springback is pretty much a guess, a composite of strake width, strake thickness, curvature, and the number of strakes in the assembly.

Before we can glue the stakes together we plane the edges to get a very tight fitting glue joint. It is a very satisfying thing to take a single shaving off the edge of a board 16' long. After the edges are planed we then sand the very carefully with a small block with 80 grit to give some tooth for better adhesion.

Here the strakes are prepared and on the bending form ready for gluing.

Here you can see the side covering boards, one set glued and clamped, and the other ready for gluing.

Now we have glued and clamped the aft board. The next step will be to form the coamings . That will be in our next post.