Wednesday, 2 October 2013

Sanding an Old Boat

I have been sanding and sanding. Getting rid of yellow Gel-coat and cutting back to pristine white. I have polyester in my eyes, my ears and my hair. It gets into your clothes and it irritates especially if you break into a sweat. I have a face mask but I can still taste it.

It’s all about getting an acceptable finish. My good friend John suggested the 100ft test. Basically, if the boat looks good from 100ft, then you needn't sand, compound or polish any more.

I applied this test to other boats last week by focusing on several boats laying to swinging moorings in the estuary, and then visiting each in turn on my kayak. The closer I got, the more the dings, chips and imperfections became obvious. From 100ft however, even some quite sad and neglected craft seemed fine.

So, I guess I’m inclined to a more rigorous standard. My good friend Helge provided advice at the other extreme – sand down to grades P1000 and then P2000 used wet. Problem is I couldn't source sandpaper so fine – so I settled for P600 as the finishing grade. To date I have sanded, compounded and polished the cabin sides. Other parts of the boat have been sanded to P600 but not yet compounded or polished.

So, is P600 enough? Well ‘yes’ if you apply the 100ft test but ‘no’ if you apply a 15ft test. A more compelling question for me is ‘For how long will she look good?’

I ask this because when I was sanding her down, I noticed that much of the grime on the gel-coat was embedded in grooves previously created by sanding discs. The grime actually followed circular patterns – so this boat has been sanded back before, but not enough, or at least – not fine enough. The grime has returned and settled wherever it can get purchase, i.e. in those grooves which should have been sanded away with finer and finer grades.

Ok so here I am trying to apply a test, achieve a standard, that only time can validate. It does seem however, that the finest finish I can get will be the most likely to stay clean. So, it’s back to Helge and the P2000 grade sand paper. It’s a bit depressing to think that I need to keep sanding with P1000, P1500 and then P2000 wet and dry, especially on the two cabin sides which I have already polished – but I feel I have to do right’ by this little boat. It’s as if there is a belief (call it superstition if you like) that she’ll look after me at sea, if I do right by her during the restoration process.

So, the question last week was - ‘Where I can obtain this mysterious P1000 and P2000 paper that has eluded me so far, and can I buy it cut into discs or triangles for use with power tools?’

The answer came to me on Friday when I had dinner and more than a few drinks with a neighbour in the village. Andrew has just become the proud owner of a Cornish Shrimper, perfectly seaworthy but in need of a facelift. Guess what? He’s got P1000, P1500 and P2000 sanding discs – I saw them and held one! I had the holy grail of boat restoration in my hands. Andrew is a car enthusiast as much as a yachtsman so whereas I was seeking these papers in DIY stores and chandleries, Andrew simply headed for the nearest vehicle body repair shop and came home with the goods. Since then I discovered its also available at the following link:Sungold Abrasives 023212 5-Inch by 5 Hole 1000 Grit Premium Plus C Weight Paper Hook and Loop Discs, 25-Pack  

I went to St Malo) on Monday and now I have my own supply of discs – P800, P1000, P1500 – sadly they are out of P2000 at the moment but I also have a P3000 disc which I am told is the final disc used by professional polishers – so I have a further week or two of sanding to do. Yippee!