Skegs Fitted

The Water Rat has 2 skegs to give it some directional stability on the water and to allow it to be dragged more easily across land by the bow. I experimented with a scrap plywood mock up to see how big they could be. Starting with this:

This is the biggest a skeg could be without projecting below the lowest point of the hull. It just looks way too big and, if there were 2 of them. they would look silly! So I cut a strip off and tried it again. After several trimmings I settled on a skeg that is slightly larger than those shown on the plan (without any dimensions). Here are the skegs glued in place with fillets done.

 

 

The next step is to lay some fibreglass cloth over them to give additional strength and to protect them when being dragged over grass and sand.

Gunwales

The firbreglassing is finished, the seams and overlaps are filled and the sanding is done, at least for the time being.

I've fitted some 12 mm square gunwales to stiffen up the top edge of the side plank. I will add some strips across the decks to stop water running into the down into the boat.

Here's what it looks like now.

You can see some pink patches. This is epoxy bog with some red paint tint added so that I can see where the last lot of bog was applied and where I need to sand.

Fibreglass on Bottom Panels

With the decks in place there was no longer any excuse for not starting the fibreglass covering on the outside of the boat. After a final sanding and a thorough vacuuming and a wipe over with a cloth dampened with acetone and several deep breaths I began.

I mixed batches of epoxy as I went along using Boat Cote resin and the "tropical" hardener to gain a longer working time. The epoxy was poured into a paint tray and rolled onto the boat with a 75 mm roller. Draping the cloth over the boat was difficult because it sticks as soon as it touches and pulling it up to rearrange it tend to stretch it out of shape. However, I managed to get it on. I rolled it with a serrated roller to get the air bubbles out and rolled more epoxy on to make sure the glass cloth was saturated. It's a tricky process needing just enough epoxy to saturate the cloth because any excess will tend to run or sag.

That's what it looked like after I had finished. Pretty good I thought as I closed the shed and left it to dry out but while the epoxy is wet and shiny it is hard to see the runs!

Even on this small boat I learned several things about laying fibreglass cloth. Not in any sort of order:
You need good scissors to cut the cloth cleanly.
It would be a good idea to cut the cloth to shape before starting with the epoxy.
You need scalpels or razor blades to cut the cloth in places where it refuses to lie flat, eg on curving corners. The cloth stretches within limits but I needed to make cuts so it could overlap in a few places.
Cutting the wet cloth with scissors is the end of the scissors, I could not clean them. Fortunately I discovered this on cheap scissors!
You need at least one helper because you are working against the clock. A helper can keep up the supply of epoxy to avoid pauses on the application. A helper can help with the rolling on of the epoxy, a priming coat which will soak in pretty quickly and a second coat so the surface is wet. Two people can more easily position the cloth, roll it out and roll on more epoxy to fill the cloth.
The foam rollers can't be cleaned - I put one in acetone to reuse on the next stage but the acetone destroyed to plastic tube.

Decks Fitted

Today I fitted both decks. I gave the underside of both deck panels a priming coat of epoxy and left them for a while until the epoxy started to go off. Then coated the inside of the compartments with epoxy and gave the underside of the deck panels a second coat. Thickened epoxy was applied to the glue line between decks and hull (plenty of epoxy to make sure that the joint was full of glue) and the panels put in place with temporary staples to hold them down. With them stapled down I cleaned up the excess epoxy, easy on the outside and messy on the inside where it had to be done by feel. Here are the decks in place.

Fore and Aft Decks

I've tidied up the supporting shelves for the decks and cut the ply panels to fit. I added a block under the forward deck so that a cleat can be fixed to something more substantial that the 4 mm thick ply.  It is clearly visible in the photo.

As I glue these panels in place I will give the underside of the deck a couple of coats of epoxy. When the first of these is tacky and ready for the second coat I will put another coat of epoxy on the inside of the compartment and finally, put the deck in place on a bed of thickened epoxy. This should ensure that the inside of the compartment is completely sealed.

Fitting Shelves to Support the Decks

The decks over the fore and aft buoyancy compartments need a shelf (or inwale) to provide an area for glue to hold them in place. I made these out of some 12 x 12 mm cedar strip, light and glues well. Here are photos of these strips being fitted in the boat.

The inside seams have been taped and the fore and aft compartments have been given two coats of epoxy applied wet on wet. This has been roughly sanded (appearance not important inside the compartments!) and I will give it another coat of epoxy when the deck panels are glued in place.

Fillets on Inside of the Seams

After removing the cable ties the inside seams have a large epoxy fillet applied. Various size spatulas with a semi circular end are used to create the fillets. The spatulas are home made out of scrap ply. The fillets use a surprising amount of epoxy and I ran out of resin. Fortunately the last cup of resin finished the job! Here are a couple of photos showing the fillets.