Saturday, 28 March 2015

Will it ever end......

As I am working Saturday I decided to take Friday off as the weather looked good and it turned out very fine in the end.

I was continuing my mission to peel back the layers of epoxy paint back to the gelcoat/primer, the Port side is finished now and its just the starboard side left to do.

I was hoping I would manage to complete this in a day but it turned out that time just wasn't on my side, it takes much longer than you would think and is quite hard on the arms.

I have tried several different methods with 2 polishers and a variety of pads and disks, by far the easiest way is a mini grinder fitted with an 80 grit flap disk.

It doesn't too long before the disks clog so I needed to have a good stock, I spent 6 hours grinding and used 4 disks so not that bad.

I bought several types but the most economical are the ones that cost £1 each! They seem to last just as long as the ones that cost £3.50, although if your were using them on metal that may be different.

I didn't manage to finish it all and got about three quarters of the starboard side hull peeled, although I still had plenty of daylight left 6 hours was more than enough working with a grinder what with the noise and dust, without the fact that i was starting to find it difficult to hold my arms up.

Another job that needs doing before the primer is applied, is to scrape back the boot top, this is the top 6 inches of anti-foul all around the water line that is particularly thick, often this can be 2 or 3 times thicker than what's applied to the rest of the hull.

Previous experience has taught me that scraping anti-foul is a painstaking task that leaves you with an awful lot of filling to do and really is a marathon, sanding or grinding anti foul off is a particularly nasty and dangerous practice due to the chemicals that can be inhaled in the dust, it would also be unacceptable in most yards, not so bad if you can keep it wet but dry sanding is a no no.

With this in mind I have decided to try chemical stripping, normally you might use nitromoors or similar, downside to this is that it damages gel coat and is far from ideal for boats, the alternative would be something like dilunet gel, but as with most things in the marine trade can be quite costly.

I did some homework and decided to try a caustic soda solution which does not harm fibreglass, 250g of caustic soda added to a litre of cold water and some wallpaper paste to thicken, again this can cause burning to the skin so normal precautions were taken.

Most of the advice I read suggested leaving it on for 12-24 hours before scraping off, as it turned out I needed to return to the boat Saturday afternoon which gave me the opportunity to have a look after 24 hours to see if it had made a difference.

It obviously had an effect, wasn't  sure how many layers it would take off so I decided to scrape a few sections, I found that it had worked better on the sections that I had stippled as opposed to using long strokes and I found that there were at least a couple of layers that came off at ease with a quick scrape.

Not sure it will make a difference but decided to leave it on until next week and will see what the situation is then, if needed I can always go around with a scraper and apply another coat if needed.

As with most projects for every job you plan several more are found along the way, one of these I only noticed on Friday, whilst grinding the rudder I noticed that the bottom couple of inches of the skeg had broken away on one side.

My initial instinct was to work out how to rebuild it to its original shape, this can be done but will take some time as well as skill with resin and fibreglass, upon reflection I wonder if there is much to be gained so I will grind it flat so it is equal then asses it again, it maybe the case that I leave it flat with just some fibreglass tissue on the underside to seal it off.

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