Sanding undercoat/top coat with random orbital sander???

[Robert Wilson]

Is it ok/sensible to use a sander for fine sanding (400 grit), or must I use sheets and sand by hand to prepare the final u/coat and then top-coats?

I'm going to use International Perfection undercoat (2-3 coats) and gloss (3 coats). These will be on top of Interprotect epoxy primer (2 -3 coats)

Khamsin has suffered badly over the years, but after 63 hours of diligent scraping, filing, fairing - three times over - the hull is in fine, smooth condition.
Epoxy primer should restore the surface where, in places, it's through to the lay-up and the gel-coat is less-than perfect/sound.

My aim is for a superlative, hard-wearing finish which will see me through, hopefully, for 8 - 10 years.
After which time she'll be somebody else's problem!!

As you can guess, I'm a first-time boat painter!

Thanks in anticipation. As usual,

Robert

EDIT: Whoops, looks like I posted something similar before. But this is specifically about fine sanding of the final coats.

 

[Tranona]

If you do a good job on the paint you will have little sanding to do. Wt and dry use wet on a rubber block then wash thoroughly and use a tack rag before the next coat.

 

[Robert Wilson]

I have a rubber block, but won't that cut too deeply on the curved hull?

 

[Tranona]

No. With 400 or 600 you will just be knocking the tops off any specks. If you get runs you will need to be more aggressive anyway.