Building the Ballast Tanks
from start to finish

Fitting the bulkheads

Saturday, March 15th, 2008

Saturday at Howth, drizzly weather, today we fit the bulkheads with epoxy. However, everything is a bit dusty because yesterday an aggressive angle grinder was used to grind back the flowcoat on the keel pan, prior to strenghtening. That is an electric oil heater in the middle of the sole, trying to dry out the boat, assisting the de-humidifier.

Fitting panels 1

Here the portside ballast tank bulkhead has been fitted, using WEST epoxy thickened with colloidal silica to make fillets on each side of the panel. Later, biaxial fibreglass tape will be epoxied in place to provide great strength. An angle grinder was used on the inside of the hull to remove the white flowcoat and to provide a roughened surface, a good mechanical key for the epoxy.

The copper pipe on the right hand bulkhead is the gas feed to the cooker. The large white pipe is the fresh water inlet to the tank. The funny circles in the picture are specks of gelcoat dust floating in the air.

Fitting panels 2

Here is the starboard side, with the grey diesel pipe and a number of electric cables, prior to fitting the tank bulkhead. The black silage tape is applied to protect everything from stray epoxy during fitting of the bulkhead.


The starboard bulkhead has been fitted, again with epoxy filleting.


Here is the starboard side insert to block off the storage bin…it will become part of the ballast tank.


Easter Weekend

Wednesday, March 26th, 2008

Four more days working on Dinah last weekend. No huge visual transformation like the weekend before, but a lot acheived.

On Friday myself and Bob cleaned up the new keel pan. We ground down any little bumps or sharp bits left behind when it cured, to make the whole thing really smooth. Then the edges all round were straightened and made really smooth, then masked off, so when the whole thing is flow coated in a few weeks time it will look like original build detail and blend in perfectly. Finishing that major job off will really be a big moment. Hopefully everything will be ready for it the weekend after next.

Saturday Bob brought along the front panels of the ballast tanks for initial fitting. We had to make a few small adjustments, but soon they fitted perfectly.

Ballast Tank Front Panel Ready for Fitting

We made templates for the baffles, which will be made from the same plywood as the tank panels. We also fitted the water ballast pump and engine blower, and fixed the door (Hmm, who will I need privacy from in the middle of the Atlantic?).

Sunday and Monday I got out the angle grinder again (I’ve grown to hate it…) to grind away the parts of the boat where the ballast tank and baffles will be bonded to. It’s a really horrible job with lots of airborne glass dust. I’ve taken to wearing two masks when doing it, and it’s still horrible. But it’s a necessary evil, and hopefully this is the last of it. You can see on the picture below how the surfaces are down to bare glassfibre where the tank panels and baffles will be bonded.

Hull to Tank Join

A huge clean up afterwards and the boat is looking great. Even the cooker is sparkling now! More after next weekend… Electronics should start arriving soon!

Fitting the first ballast tank hatch

Thursday, April 3rd, 2008

Time to drill and fit the ballast tank hatches, this one is the starboard aft hatch cover, the closed cell neoprene tape (6mm thick and 25mm wide) has been fitted.

hatch 1

A cardboard template was made as a drill guide, the first five holes have been made, M6 bolts installed to keep it all steady.

hatch 2

Holes have been drilled, absent a drill press, some care is needed to ensure the holes are absolutely straight. The ballast tank panel has three coats of epoxy resin on the inside (the wet side) and two coats on the outside (the dry side). The hatch covers get the same treatment.

hatch 3

Next, a 13mm spade bit is used to widen the 36 drill holes in order to countersink the bolts. A bit of blue tape shows the depth (4mm) to drill.

hatch 4

All of the bolts have been inserted and the nuts tightened from below (thanks to a battery drill with a 10mm socket attachment). The neoprene has squeezed from 6mm to 2mm.

hatch 5

The countersunk bolts have been inundated with thickened epoxy resin, which, when dry, will prevent the bolts from spinning as the outer nuts are loosened or tightened. The blue tape is there to catch any epoxy overspill. If this first hatch releases okay, the other five hatches can be installed in the same way.  If not: back to the drawing board!

hatch 6

Ballast tanks 2

Saturday, May 24th, 2008

We have fitted the starboard ballast tank, with hatch covers temporarily in place.  Next step is to seal the seams with biaxial fibreglass tape and epoxy resin.  Note the quality black stereo speaker.

starboard tank

On the port side, here is the hole cut in the aft bulkhead for a sump tank which will be fabricated on the aft side of the bulkhead.  Inlet pipe (one and one half inch) and crossover pipe (three inch) will be fitted to the sump tank.

port tank