Tuesday, May 29, 2018

End of the Sportfisherman Fairing

Kevin has been finding muscles in places that didn't have muscles before. Longboard sanding large surfaces tends to have that effect. But it is a process that must be gone through if the boat is to have a really nice standard of finish. Any shortcuts at this stage of the build will show in the final finish and take even more work to improve later.

I described the general process of filling/sanding/fairing/sanding in my previous sportfisherman blog post. Now, to round off the process, Kevin sprayed on three coats of high build epoxy for the last sanding operation. This layer is much harder than the sprayed fairing layers, so much tougher to sand. Before sanding he sprayed on a guide coat composed of denatured alcohol with food colouring mixed into it. This is sprayed on in a thin film that leaves a very thin coating of colour after the alcohol has evaporated off. Longboarding this surface removes the colour on the high spots and leaves it in the low spots of any texture on the surface. Continuing to sand until the last of the colour has gone ensures that there is no orange peel or other texture left to detract from the gloss finish coats that will follow later.
The blue in this photo is the guide coat of food colouring and denatured alcohol that was sprayed on to assist sanding.
With sanding nearly finished, the hull is showing a good standard of fairness and finish to form a smooth foundation for the high gloss finish coats.
While Kevin was developing his muscles I was stripping out the temporary frames and formwork from inside the hull, items that are no longer needed to support the hull. This is to reduce weight for when the hull is turned over.

The next step was to start building the frames around the hull that will protect it and provide support while the boat is turned 180 degrees. These frames are at permanent frames 3.5 and 7, which spread the hull weight evenly and also are of similar width, allowing two similar frames to be built. The first parts added were the bottom frames, bolted to the frame bases, stiffening them considerably. With those in place the hull was raised with a trolley jack and blocked a few inches clear of the building stocks. Then the stocks were taken apart and much of the timber reused to build the turning frames. Once the stocks were out of the way we jacked the hull again, removed the blocks and lowered the hull to stand on the frames, resting on the floor.
Turning frames built around the hull, with carpet padding between the frames and hull. The diagonal braces needed to stabilise the frames must still be added.
With the temporary frames removed, the structure of the hull is more easily seen.
Work on sanding the hull, applying barrier coat to the bottom and completion of the turning frames is continuing, in preparation for turning the hull this weekend.

This design is not yet on our website, I am still drawing it. To see our other designs, go to our main website or our mobile website.

Wednesday, May 16, 2018

Fairing the Sportfisherman

Since my last post about Kevin Agee's 26ft sportfisherman project he has completed the glassing of the planing strakes and transom, after which the hull was ready for fairing to start. The fairing system chosen is from Alexseal Yacht Coatings.
Alexseal products for primers and fairing.
First to go onto the hull was 3 coats of high-build primer applied by roller. This formed the white base onto which the fairing/sanding layers were built up. It also gives a visual warning that sanding must not go any further into the coatings, instead more thickness must be built up to fill low spots before sanding can continue.

Next came a sprayed tan-coloured fairing coat that is sanded with longboards, removing high spots and revealing low spots that are missed by the sanding boards. The low spots are filled with a grey troweled putty, followed by more longboarding. Then the sequence of fairing coat, sanding, putty and sanding is repeated as many times as necessary until the hull is totally fair.

Sanding each time until the white primer is just starting to show on the original high spots ensures that there is not unnecessary build-up of fairing material on the hull. This is when the first fairing step showed its value. That first step was sanding out the bulk of unfairness from the raw wood strip surface before glassing the hull rather than adding filler to the low areas then glassing over them. Omitting that step would have increased the amount of fairing material on the hull, with resulting increase in weight.
This photo shows the bow after the first sprayed fairing coat. The white showing on the hull bottom is high-build primer. The edges of the fibreglass tapes on the bow show as ridges, even after feathering by sanding ahead of applying the high-build primer. The trowelled filler will be used in such areas to build them up flush.
Camo boat, good for duck hunting. After 2 or 3 cycles of sand/spray/sand/fill/sand the hull fairing is almost done. The white is high-build primer, the tan is spray fairing and the grey is trowelled filler.
Next will be a final layer of spray filler ahead of preparations for turning the hull over in coming weeks.

This design is not yet on our website. To see our range of designs, go to our main website or our mobile website.

Sunday, May 13, 2018

Argie 15 for Okoumefest

Chesapeake Light Craft (CLC) hosts Okoumefest on Saturday 19th May, next weekend. This annual event is a day on the beach with a whole fleet of plywood boats of all types available for the family to try out.  CLC cut kits for us for the Argie 15, as well as a few of our other designs. I will be there and will have the Argie 15 that we exhibited at the Wooden Boat Show at Mystic Seaport, CT, ready for sailing. This boat was built by Kevin Agee from a kit supplied by CLC and was runner-up in the sailboat division of the Concourse d'Elegance at that show.
Argie 15 at the 2017 Wooden Boat Show at Mystic Seaport.
The Argie 15 is big 3:1 dinghy, for family fun under sail, oar or outboard power. It has a multi-chine hull built by stitch-&-glue plywood methods and detailing. It can comfortably carry a family of 2 adults and 4 children for day-sailing and is also well-suited to camp-cruising. Come to Okoumefest on Kent Island, Maryland. For more information, visit CLC Okoumefest.

For more info about this and our other designs go to our main website, mobile website or our plywood kits page.

Didi 40cr2 Builder Sheri Bamboat

Sheri Bamboat is the owner of XS-Marines, boatbuilder in Mumbai, India. They built the plywood Didi 40cr2 "Stargazer" for a customer and took moulds off that boat for future production building of the Didi 38/40 design range in sandwich GRP. Today an article appeared in Indian newspapers about Sheri Bamboat, telling the story of his involvement in sailing and boatbuilding in India. Read Sheri's story in the Mumbai Mirror.

Didi 40cr2 |Stargazer".
To  see our range of designs, go to our main website or our mobile website.

Tuesday, May 1, 2018

Progress of the Sportfisheman

The glassing of Kevin Agee's 26ft sportfisherman has continued. After completing the sides and bottom with a single layer of biaxial fabric cut from a roll 50" wide, the centreline was glassed with two layers of biaxial tape. The transom and bracket followed, also glassed with biax fabric from the roll.
This photo shows all stages of glassing the hull side. The light section in the bow hasn't been started yet. The dark section aft of that has been pre-coated with a layer of epoxy. Aft of that the glass fabric has been laid back against the hull so that the contact face can be wetted out prior to being laid onto the wet epoxy on the hull. This speeds up the wetting out process of the glass. Aft of that the glass has been rolled with ribbed rollers to remove bubbles and a layer of peel ply has been applied over the top with squeegees.
A few days later, the peel ply layer has been removed and the centreline has been glassed with two layers of biaxial tape, from transom to tip of the bow.
The transom and bracket have been glassed, lapped over onto the sides and bottom of the hull. The centre portion will be glassed after the hull has been turned over.
After removing the peel ply, the hull was examined to find and repair any air bubbles that formed in the laminate. A few were found and repaired. Sanding them out with an orbital sander, I could see that most were the result of out-gassing from the wood and one appeared to be from contamination. The out-gassing bubbles have a complete coat of epoxy against the wood, while the contamination bubbles have little or no epoxy against the wood. In this case the contamination showed as a pattern of four fingertips and a palm. The out-gassing bubbles were sanded down to the epoxy coat and the contamination bubble was sanded down to clean wood, to remove the contamination. All were sanded out to form a dished profile with a feathered edge on the glass. Then a patch was laminated into each one, to be sanded flush later.
An out-gassing bubble has been sanded down to remove the glass that hadn't bonded to the wood, forming a dished surface. This is then filled with a glass patch was laid in to fill the depression. This will be sanded flush before the fairing layer is started.
Next task on the list was shaping and fitting the planing strakes, one on each side. The strakes are parallel-sided over part of the length but must be tapered both horizontally and vertically, terminating in a point at the forward end. They must also be planed to a triangular shape so that the hypotenuse matches the slope of the hull bottom over the entire length. Most of the timber can be removed with a power plane, then finished with a hand plane.

We did a dry-fit to check for correct shape, placement and fairness, held by temporary screws. The target is a fair curve when seen from all directions, as well as matching alignment between the two sides when viewed from the front. The screws were used later for alignment to ensure that the strakes were glued on in exactly the right positions.
Planing strakes dry-fitted for alignment check.
Planing strakes glued on. After removal of the screws they will be glassed over.
This design is not yet on our website. To see our range of designs, go to our main website or our mobile website.