Monday, January 30, 2017

Update on Our Argie 15 Project

Kevin Agee is working hard at our new Argie 15, completing epoxy coatings on the inside of the boat, including sanding and other tidying up to give a nice standard of finish. These smoothing tasks are worth doing all through the build, or the runs and bumps will accumulate into lumpy surfaces and rough edges.

A few years ago I was asked to do a talk to a yacht club meeting. The club members were building some sailing dinghies at the time, which they showed me. The plywood stitch-&-glue hulls had been built and epoxy-coated. Later, during my presentation, the members were looking through my photo albums of my own projects. The photos of the Paper Jet, with its mirror finish, brought a few questions. They wanted to know how I had achieved such a finish, using the same build method as their lumpy boats.
A finish to make any builder proud of what has been achieved. Get there by simply sanding out all imperfections on each coat before applying the next. This is not an Argie 15, it is the prototype of the Paper Jet.
The secret is to apply enough epoxy in each layer to do the intended job and no more than that, then to ensure that it doesn't dry with runs to spoil the surface. If the coating is too thick then it will run. If you leave the runs then apply the next coat, the runs will become accentuated by the next coat of epoxy and you will have even more runs. After three coats of epoxy the surface will be so lumpy that you may need an angle-grinder or a bucket of filler to smooth it out. It is much easier and more satisfying to just sand out all imperfections on each coat before commencing the next one. The epoxy being used for the Argie 15 build is MAS low viscosity epoxy. Being mid-winter, we are using the MAS fast hardener to shorten setting and curing times.
MAS low viscosity epoxy with fast hardener speeds up curing in the frigid winter temperatures.
The first coat will take the most epoxy because it will soak into the wood. Add more epoxy to areas that look dry until a thin layer stays on the surface. The second and third coats will need less epoxy because it won't soak into the already sealed surface.

The holes for the inspection covers have been cut. We have 15 of them in total for the boat, to get access throughout the inside of the hull. These under-seat spaces are not only buoyancy, they are also dry-storage compartments for clothing, food packages, tools etc. They need to be accessible for cleaning and to retrieve lost items; you don't want to have spots that even the longest arms in the family can't reach. I elected to use Viking 5" inspection hatches, which are currently in the mail. Kevin used a large hole saw to cut the openings. They can also be cut with a router fitted with a circle-cutting attachment or it can be done with a jigsaw. These latter two methods would be easiest done before the panels are glued into the boat but the hole saw method is easy enough to do in the boat.
Holes for access hatches (inspection covers) cut into all of the compartments.
The drains through the centre seat have also been installed. These were made from a length of 32mm ID PVC pipe that was cut in half lengthwise to make two U-sections. These have been glued to the bottom panel and then glassed over and epoxy-filleted. The ends project through the bulkheads and will be trimmed flush. Don't forget to paint your three coats of epoxy to the hull skin before gluing the half-tubes in place, don't leave this for later.
Drains passing through centre seat, glassed over and filleted.
Kevin has also been working on the mast step and partners, getting them ready to glue in when the hull is ready for them.
Mast partners on the left, mast step on the right.
For more on this and our other designs, go to our main website or our mobile website.