Dings and scratches

[kingfisher]

Im going to repaint the topsides next week. The hull is already fully cleaned and degreased. Phase two is getting rid of all the nicks, scratches, pits and dings she acquired from being a scout training boat. Phase three is sanding, phase four is painting in a two-pack paint.

The boat is under shelter in a rather dimly lit shack.

1) What is the best way to spot every nick and scratch? A halogen floodlight at an oblique angel? A UV lamp? Blacklight ? I'm on a ladder.

2) Sanding before painting: I'm planning to sand the hull with an even gritt, to assure a good grip for the paint. What do i use? A 120 ? Isn't that too coarse?

<hr width=100% size=1>Group of people on the pontoon: skipper is the one with the toolbox.
http://sirocco31.tripod.com

 

[insider]

a very thin mix of epoxy filler and a spatula /scraper, call it what you will ,[an old credit card is good,] pull a thin scape of filler over every visable blemish with a strong light at a angle to the hull.
since you sound like you still need to sand it a thin coat that is extra to the ding or scratch will soon sand off.
remember never jump sanding material, ie wet and dry paper, by more than two grit sizes as while you sand you scratch and each finer level of paper polishes out the previous scratches till you get the mirror finish you want, and your boat deserves.
re paper grade that depend on how bad the hull is and how much you need to tidy up.

<hr width=100% size=1>Logical progression is fault finding tool in every tool box.
Regards,
Insider

 

[kingfisher]

1/ Blemishes
Here's the problem: I want to make sure that I have filled every scratch before I paint, because it will show once the lacquer is applied. So what's the best way to spot them all?

2/ pre-paint sanding
I'm not worried about sanding to a fine polish, as I will be painting. I just want to make sure that the paint has a good grip. But if I sand with a paper that is too coarse, it will leave marks.

<hr width=100% size=1>Group of people on the pontoon: skipper is the one with the toolbox.
http://sirocco31.tripod.com

 

[Phoenix of Hamble]

Kingfisher,

If you are intending to paint the boat anyway, apply a very thin 'guide coat' from a spray... aerosols work fine... make sure you get paint compatibility.... then when you prep sand the hull, use a largish flat pad to sand off the guide coat, and the dings and scratches will retain the paint where 'normal' undamaged areas will sand off.... this is by far the easiest way to find all the scratches.... and is the technique used by high quality vehicle painters to get that glorious sheen that is sometimes seen on classic cars....

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