Dogbolter's Hull

5 December 2011

Dogbolter is in my garage.  I have a sideways trolley for boats which don't quite fit.  It is much easier on the auld back to work on boats when they are on their side, rather than stooping low over a hull upside down on its trolley.  Besides, the Dog doesn't have a trolley. Many thanks to Dublin area Fireballers Barry, Dave, Glenn, Henry, Mary and Mick who helped me secure the boat and her broken, rusty and rotten trolley onto Louise's road trailer and home to Terenure.  The mast and boom are stored on the garage roof. The rudder and centreboard are in the store room, not bad condition.

I have begun scraping off the horrible green paint.  Dogbolter was not built with gelcoat on the hull.  Instead, when it came out of Peter Delange's mold it was spray painted with a dark grey primer / undercoat followed by a lighter grey. I have no clue as to what kind of paint was used.

At some later stage, a numpty owner brushed on a coat of grey primer.  Two years ago, the last owner brushed on what appears to be Primocon primer followed by the green topcoat which I think is International Perfection "Jade Mist Green", also brushed.  That's five layers of paint!  In some areas, three layers scrape away quite cleanly, even showing the gloss of the original second coat.  In other areas, it's a bit of a struggle.  The two-pack green paint is so hard that sanding it off is simply not an option.

This is the tool of the moment: a Stanley Window Scraper.  I use a very shallow angle to scrape off the paint.  Each blade lasts about 20 minutes, then flip the blade over for another 20 minutes.  Then insert a new blade and continue.

I am finding previous repairs such as this one which is obviously Gelcoat Filler.  Those "islands" of green paint are dents in the hull, the scraper skates over them.

7 December

A couple of hours scraping (three blades) and one hull panel is ready for light and careful sanding, 320 grade 3M Hookit Gold on a random orbital sander.  Dust outside is better than dust inside. My car is the same colour, a complete coincidence!

I found a "rocker bump" at one of the hull measuring points at the aft end of the centreboard case.  It's about two mill proud.  And it's a very gummy kind of filler.  The muck around the centreboard case is impact cement left after I pulled off the centreboard gasket.

In a few places, the outer layer of glass has been pierced / punctured.  I use Mr Dremel to grind through the foam layer to check that the inner kevlar layer is still sound.  A small wound, it will be filled with epoxy and microfibres.

Here, the chine is split and hollow underneath.  Hmmm. A builders failure, resin starved at the foam joint just inside the outer layer of glass.  Easily fixed with epoxy and microfibres.

Small hollows (the green islands) can be sanded out with Mr Dremel and levelled with Marine Filler. There are several spots featuring the cream coloured filler, previous repairs?  The brown area is the glass weave and brown foam sandwich, a large dent which I have sanded.  It will be filled with epoxy resin and fine fairing filler before being wet sanded smooth.

Several hollows here, at the starboard bow, rather artfully abstract.  Remember: dark grey first coat of paint, light grey second, off white third, silver grey fourth, green fifth coat of paint.

6 January 2012

Lots and lots of wet sanding, filling dents with epoxy resin and fine fairing filler (if more than 1 mm deep) and marine filler (if less than 1 mm deep).

The side chine was badly rounded after all these years, so I applied a coating of epoxy resin with microfibres to tidy up.

This little SurForm does a good job of skimming of the excess cured resin, followed by wetsanding with 180 grit.  You can just see bits of masking tape I applied to collect resin overflow and delineate the edge of the chine.

12 January 2012

Starboard aft has been sprayed with grey primer, a tell-tale coat to show any and all blemishes.  My plan is to get the hull to this stage and then final fair and spray in early May.  That's an ancient Fireball red spinnaker catching the overspray.

A picture above showed hollows beneath the rocker chine forward of the centreboard case.   Here the hollows have been filled with resin and microfibres and sanded smooth.

The bow plate...plenty of previous repairs here.

The alloy keel band on the portside rail has been badly bent, so I used Mr Dremel with a cut off wheel to remove the damaged section.

Here it is, resting on the starboard rail, bent in two dimensions.  I'll need to obtain a new length.  Interestingly, the keel band was attached using grip-fast nails hammered into the epoxy rail.  I'll use countersunk screws to refit the new 70cm length.
The finished hull, spray painted with grey primer and faired with 800 grit wet and dry.  New slot gasket has been installed.  A good bit later than planned, but it has been a busy summer. 
The distinctive "wide bow" is quite evident.

Back to the Intro page, Repairs to the HULL, to the DECK, to the COCKPIT, to the FOILS