Paint

[Admin]

Found some more info on boat paints. All these sites sell Epoxy paint systems especially designed for painting GRP boats. They also have guides and videos on how to prepare and use them.


www.yachtpaint.com

www.marineware.com

www.blakespaints.com

[Ian]

When I bought my Portafold it had been brush painted both inside (in emulsion, including the quilting! ) and outside (many layers with the final one in something that looked like sandtex ) so I took the plunge and had it soda-blasted.

The intention was to do the inside, as well as the outside, but I've had to hold off on this because I found that 8 of the 17 body hinges were broken and had been for some time - no wonder the previous owner erected the damn thing and then left it like that!

Anyway the blaster did the work on the outside yesteday morning and I'm pleased with the results, on the whole (though I'm not pleased that he pulled one of the strap staples off the roof and put a 4" split in the edge of the roof - he obviously took my assurance that "the roof just lifts off" too literally!) The blasting has removed 99% of the paint and left a lightly keyed finish - much, much easier than Matthew's 3 days!

That was the good news, now for the bad - the blasting through up a problem which caused the blaster to ease off on the process and leave some areas undone - pinholes, lots of them and some as much as 1/8" across. His view was that it was probably poor workmanship in the original moulding of the panels, but, on reflection, I came up with an alternative suggestion: osmosis. Osmosis is the scourge of elderly grp boats and seems to affect coloured gel-coats more than clear; but basically water gets into the gel-coat and causes blisters and worse. My Portafold had been poorly painted with several layers of thick paint but the gel-coat does not appear to have been keyed before painting so there was poor adhesion - the paint was sitting like a shell on the panels and it was obvious, from the mould under the paint, that water was trapped in there - hence osmosis. Elementary, my dear Watson. Well, I think it might be the answer, anyway.

It doesn't matter what caused it either way, I've got lots of gel-coat filling to do

[Admin]

Ian,

Have you got those before and after pics? It'd be great to see how the soda blasting went.

[Ian]

Hmmm, I have pictures on my new digital camera, but there is a quantum leap needed twixt camera, or rather my knowledge of the buddy thing, and the forum........

[Admin]

I've found the pictures I took when I stripped the Daytona yellow paint off the bottom part of my Portafold, Easter weekend 2006.

Since these were taken a lot of T-Cut and polish has been used to get it back to the original cream gel coat, but it was well worth it.

Nice and bright yellow, plastic bin liners over the wheels to protect them from the paint stripper.

You can see the bits that have been started on on the off-side front corner.

The yellow patch is actually a repair that they coloured yellow. Took a bit of scratching before I realised it wasn't stubborn paint!

That pin striping is hanging on for dear life.

That pin striping sticks really well!

[hattytheherald]

Hi all

Mark repaired and painted our roof last year. He used International Paints - toplac. He took it right back and repaired large sections before 2 coats of primer (Again from international paints) and then 3 coats of the toplac, slightly thinned with the appropriate international thinner. His words were " its a pig to spray". Two man job - apply with a small foam roller, then lay off with a decent quality brush. Better to build up multiple thin layers than it is to whack a thick coat on as it runs.

Once hardened, if you want a real flat, perfect finish, flat back with 6-800 wet n dry with water and soap. Then polish with G3 polishing compound and it comes up lovely.

Mark's upset as last year he could not get the cream colour in this country and now they sell it so may be redoing the whole van in cream.

[Ian]

Found a neat way to fill those pin-holes - rub the filler on with a rag.

I can't claim to have invented the process cos I got the idea from a chance remark by the local boat-fettler, he uses a rag to spread filler onto hulls after they have been blasted as part of the osmosis treatment process.

Anyway, I tried it with some gel-coat filler and it worked a treat - just spread the filler onto the affected areas rather like rubbing polish onto a car. You have to work quickly as it goes off in 10 minutes, so I only mixed small batches.

Don't do what I did and not wear a disposable glove under the rag - the filler works it's way through the rag and sticks very well to skin (it does wear off after a week! ).

Grumpy Northern git

[Ian]

Soda Blasting II

I've found another downside to soda-blasting - I've had several sessions attempting to fill the millions (well hundreds) of pin-holes that the blasting exposed and, as a consequence, the painting hasn't happened, yet. The downside is that the lightly keyed surface that the blasting left attracts and holds grime beautifully - the damn pressure-washer has only shifted the surface stuff - obvious in hind sight but my own fault really - I suppose the ingrained stuff will have to stay when I get around to the painting.

Ian

[53catalina]

I've rubbed mine down using 400 grade wet and dry paper, and then used Crown X-treme Primer (from a Crown Decorators Store). This sticks like the proverbial to GRP and makes a good base for a top coat.
The top coat on the roof has been painted using Dulux Weathershield Gloss which I had matched to my cars colour. The sides will be gloss White by Crown. I have applied the paint by roller, which leaves a slight orange peel affect on the paint, but on the whole looks good.

I will post up some photos tonight for you of my progress so far, or look here
http://s61.photobucket.com/albums/h59/5 ... Portafold/