December, 2014

The Carlins (Continued)

After testing the fit of the starboard deck carlin, I taped the deck edge and setup a dry run with the clamps to see where the clamps needed to go to ensure a tight joint.








Prior to fitting the carlins, I scarphed both carlins' ends to 13 cm off the ends to round off nicely around the front and aft curves and be ready to receive the next pieces.

To protect the gunwhales I used a pipe insulation foam tube that comes with a slit on one side.

View of the transom from the bow. I marked the location of the different clamps along the carlin.

I used a cedar timber as counterweight on the port side as the starboard side clamps were heavy enough to tip the boat a bit over the cradle.

Depending on the angle of the carlin, I used a smaller clamp to secure the bar clamp and prevent it from slipping

Same counterweight technique used on the starboard side when clamping the port side deck carlin. 

Then, the all important dry run to set up the clamps at the right place to obtain a tight joint between the carlins and the top edge of the deck





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The dry run setup view from the front.

Placing the clamps near where I'll use them during fitting.

View of the port side from the stern after fixing with epoxy resin and colloidal silica.

View of the port side from the bow after fixing with epoxy resin and colloidal silica.

View of the port side carlin after removing the clamps. I used the hand plane as the first step to remove the excess material.

The hand plane does an excellent job at removing the excess material and the blue tape at protecting the top of the deck.

View of the port side carlin after removing the clamps.

The inboard edge of the forward deck is covered with a 60 mm wide x 2 mm thin Mahogany veneer I cut with my table saw. The veneer goes around from the inner edge of the king plank to the end of the scarph on the starboard side carlin. The veneer bent nicely around the curves without problems and were held in place with clamps during the dry run show on this image.

Because of the torque applied during the three-dimensional bend, small gaps appeared between edge of the deck and the veneer.

To ensure a tight joint between the deck and the veneer, I used the same counter torque and clamping technique used when fitting the rubbing strakes.

I carefully clamped a cedar timber over the deck where the timber was not actually touching the deck. I used scrap pieces of wood in between to prevent imprinting on the deck. Later, I used bar clamps to pull the upper edge of the veneer tightly against the edge of the deck. 

View of the counter torque and clamping technique used on the forward starboard side.

 View of the counter torque and clamping technique used on the forward port side.

When building the deck frame it really pays to plan where to place the reinforcements blocks to also serve as clamping blocks perpendicular as much as possible to the tightest curves.

Another view from behind.

And a final view from the port side, completing a 360° view of this clamping technique.

I have collected a small amount of Mahogany dust from my belt sander to mix with epoxy and apply it to any of the deck joints. This ensures almost invisible joints once varnished.

For the transom veneer I used two separate pieces since I didn't have a plank wide enough (about ~16 cm) to trace the transom curvature and cut it out in one piece.

View of the transom after adding the protective blue tape and ready to fit the transom veneers.

View of the transom from the starboard mid section after applying epoxy resin and colloidal silica to fit the transom veneers in place and securing the pieces with a few clamps.

View of the transom from above after applying epoxy resin and colloidal silica to fit the transom veneers in place and securing the pieces with a few clamps.

The ends towards the port and starboard carlins were scarphed to meet the corner pieces.

For the aft corners around the transom, I followed a similar technique (if not the same) as used by Laurie Smith on Rob Holroyd's MR 3708 Wicked.

Designer Keith Callaghan was kind to share the reference photographs and explain the technique.

A veneer is fitted to the port side rounded corner with epoxy and colloidal silica.

A veneer is fitted to the port side rounded corner with epoxy and colloidal silica.

View of the concurrent fitting of the venner over the aft corners.

View of Pícara from the bow after fitting all the carlins and inside veneers.

View of Pícara from the bow after fitting all the carlins and inside veneers.

Next, as with the rubbing strakes, I followed the same process to remove the excess material until the top of the carlin is flush with the top of the deck.

1) Shaving, 2) Sanding with an electric palm sander, 3) Hand sanding.

Here's an image of Pícara after sanding down the top edge of the carlins and inside veneers.

Next, I traced the bottom line of the carlins from the top edge of the carlins and veneers based on the dimensions recommended by Keith Callaghan and the ones I chose around the curves to give Pícara the stylish look she deserves.

For tracing the bottom lines at the forward and aft curves, I used a piece of scrap 3 mm plywood I had previously cut across the grain. It proved very flexible and did the job without a problem. 

Rough finish view of the aft starboard rounded corner after shaving off the extra material.

Rough finish view of the aft port rounded corner after shaving off the extra material.

Rough finish view of both aft rounded corners after shaving off the extra material.

I went around the inside shaving and rough sanding of the bottom edge of the carlins. Rough finish view of the inboard edges of the forward deck after removing the excess material on the bottom edge.

View of both aft rounded corners after rounding off and smooth sanding the top and bottom carlin edges.

View of the inboard edges of the forward deck after rounding off the edges and smooth sanding the veneers.

Carlins accomplished!

I then fitted a rough block of Mahogany to cap off the end of the king plank.

Later, after sanding the king plank's end cap down to about 13mm of thickness, I fitted a 15cm x 4cm x 12mm piece of Mahogany stock to be the wedge under the mast step.

View of the Mahogany stock wedge for the mast step.

Selden mast step over the wedge.

Thank you for visiting my blog! Until next month.

Cheers and happy sailing in 2015!

November, 2014

The Rubbing Strakes (Continued)

Next I sanded and finished fairing the entire outer face of the rubbing strakes. Then, I trimmed the rubbing strakes to width per station based on Keith Callaghan's drawings. I would recommend leaving only 5 mm extra material on each end for margin of error.

Unfortunately I didn't do that and decided to cut the excess material after fitting the rubbing strake. I used my circular saw and used an aluminum ruler as a rip fence. It worked well.

Between Station 2 and 3, the rubbing strake begins to widen. I chose to begin the transition at 13 cm before Station 3. Then, at Station 4 it reaches its full 50 mm in width.

I marked the profile of the rubbing strake with a pencil and using my block plane I proceeded to shave off the excess material until the desired width was achieved.

Between Station 6  and 8, the rubbing strake's width changes from 50 mm down to the width of the gunwhale. I again decided to do a step down design from Station 7 to 8. Using Dad's old French curve ruler, I traced the curve I selected. Here's to you Dad!

Using a coping saw, I sawed along the curve...

...and then along the line for a few inches. Then I shaved and sanded the excess material left towards the rear.

After the rubbing strakes were cut to their width per station, I proceeded to round off the outer edges using a sanding block first followed by free hand sanding.

Port side rubbing strakes after rounding off the edges.

Starboard side rubbing strakes after rounding off the edges.

Aft view of starboard rubbing strakes.

Starboard side rubbing strake around mid-section.

Aft view of port side rubbing strake at transition point from from full width.

Port side rubbing strake at transition point to full width mid-section. 

I still have to fit the small rubbing strake section on the bow, right in front of the spinnaker chute. But I'll wait until I can fit a larger piece so I don't waste epoxy resin mix.  

The Carlins

The carlins on my boat are made of 60 mm x 9 mm solid Mahogany wood stock. I purchased a 17' x 8" x 3/4" board and cut an 8' piece for the port and starboard carlins.

But first I had to make the pattern. For this purpose I purchased an inexpensive 8' x 4' x 1/8" sheet of Lauan plywood at the local home center and cut a 12" wide plank.

It was very easy to bend it over the carlin's pine stringers around the side decks and later trace a pencil to outline the shape of the carlin.

Later I used my scroll saw to cut out the template. I added 5 mm on both sides of the lines for margin of error. This is the template I cut out for my port and starboard carlins.

Next, I clamped the template over the stringers to test its fit and realized I had to cut out 3 small notches for clearance where the space frames and the jib sheet cleat meet the carlins' pine stringers.

Then, I placed the template over the Mahogany plank and traced the pattern with a pencil.

Using my scroll saw, I cut along the traced lines on the Mahogany plank.

Here is the carlin stock at 3/4" thick.

Using my table saw, I cut the carlin stock in two identical halves. One for port and one for starboard. 

Next, I clamped the starboard side carlin in place to test its fit.

Here is an image of the process during the dry run. To get a tight joint against the deck line, I had to use bar clamps against the rubbing strakes. To protect the wood work, I used an 8' x 2" section of pipe insulating foam around the rubbing strakes.

View of the starboard side from the transom.

I'll use small clamps to hold down the carlin against the lower pine stringer.

Thank you for visiting.

Happy Holidays and Happy New Year!