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.

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

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.

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.

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.

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!

This entry was posted on Thursday, April 3rd, 2008 at 7:44 pm and is filed under Ballast Tanks.