Polishing Paint

[Rich]

Hi All

Owing to my poor painting skills, my newly painted gloss finish on the hull of the wooden Phantom I'm refurbing looks awfull despite hours of prep work preparing the old painted surface. I have therefore decided to flatten the gloss finish and then polish. I would appreciate any views you may have on the following:-

1) How long should I leave the new paint (Interlux Yacht Enamel) to harden before I try flattening it.

2) Which grade wet & dry should I use, and should I use it wet with plenty of water?

3) Is Autoglym OK to polish with or should I use something else?

Cheers
Richard

[DRLee]

I think you would be better off wet sanding the last coat flat and trying to paint again - see Ed's varnishing document for some top tips. Use a medium grade wet and dry then progress to fine, plenty of water and a drop of washing up liquid.

[Rupert]

Runs take months to dry in the middle, so sanding back will generally remove the run completely, right back to the previous coat...If you thin the paint by at least 10% before you try again, you will find it easier. I then sand the paint back with 1200 grit, and if feeling keen, use rubbing compound and caravan polish. Doen't work for runs, though, I'm afraid.

[stotty]

salut
agree with rupert although i use a moquette covered roller(last one shed some hairs - cheap french diy store product - chandlers sell better quality jobs) with about 15%dilution plus standing paint container in warm water for 30 mins - helps flow charateristic - flattening - of paint - on final coat
just used interlux on my nymph - left it 4-5 days before wet n drying with 1200 then car rubbing paste followed by brasso type liquid rubbing compound then straight car polish - bit difficult here in france finding stuff as per uk so lots of experimentation and 'that'll do'!

[stotty]

more thoughts
try using a stanley blade to scrape the surface of the run to level of surround then leave for a couple of days to dry/cure - had some success in past however more often than not need to fill the furrow of the run with undercoat ie only if a final final coat to be applied (u/c tends to be a little thicker than paint and fairly quick drying )flat it down then apply a very thin top coat layer in that area then feather area out and topcoat whole side boat etc
tony s

[Garry R]

To be fair to Rich he doesn't actually say there are runs. It may be that there are "bits" on the surface caused by dust etc and so a flat off and repaint might do the job. I have become a convert to the roller and jenny brush for paint and varnish. But those damned flies and dust get everywhere. I also agree that the Idiot's guide to varnishing is a gospel!

[Rupert]

You are right about the runs...I must be thinking of my last paint job...
For dust and flies, and a matt finish, sanding back and polishing will work, and as a matt finish is faster, just what you want! you will always have a little mark where the bits were, though, which no one but you will notice!

[Rich]

Many thanks for the input. Unfortunately there are a few runs in the paint and loads of dust. I am reluctant to start again as I am not confident about doing any better a job next time, especialy as I have to apply the paint outdoors. I was therefore thinking of leaving the paint to harden for say 3/4 weeks whislt I varnish the decks & apply non-slip to the inside., hopefully the paint will be hard enough by then to allow me to flatten the runs with say 400grade wet & dry, before moving on to the 1200grade & polish. I realise I'm not going to get a perfect finish, but as long as it's waterproof and doesn't look a complete dogs breakfast it will have to do for now, I'm keen to go sailing.

Richard

[Ed]

flattening with 400grade and then polishing with 800through1200 and rubbing compound and polish certainly makes it look a whole bunch better.....but does not really move the nasty marks. I did it once on Jollyboat after it rained at just wrong time.

won't really move runs or bad crap.

be careful with any edges, really easy to go through.

How long you wait depends on how warm and how many coats and what paint. With normal oil-based paint you should be OKish after about a week or so. You can always do the main rubbing down then and leave the polishing for a month or so.

And yes....do all rubbing down with copious amounts of water.

cheers

eib

[chris]

...and wrap the abrasive round a cork block rather your hands.

[jpa_wfsc]

I know conventional wisdom is very much pro wet-and-dry sanding. But I have always found it very hard to then get rid of all the dust. So I tried something else recently (inside an optimist)...

I was quite astonished how good a vacum cleaner is at getting rid of the dust! I have a cheapish B+Q sander which has a vacum attachment. Plugged in my Dyson, sanded - no dust and a good finish. However, the sander broke down very very fast! (About 2 hours of sanding). OK that was an old out of waranty sander, but I recon the very high suction the dyson can produce overloaded the sander. I then used a lightweigt orec hoover which has bad suction but for this job it was very effective.

I did not have to wash off the boat, and just used a tac-rag for a quick wipe-over before spraying the varnish on. Nive flat clean surface resulted (and very few ¨o¨#347; if you know what I mean).