Sanding topsides in prep for paint, what grit?

[JWalker]

I'm getting ready to paint the topsides, and have need to remove the old paint before painting....

I don't really want to use stripper, and plan to sand it back off.
 
What grit should I use? I read on interluxes forum to sand with 120 after the primer coat....

can I rip it off with 80? or mabey 80 and then 120?


thoughts?

Thanks!

[Captain Smollett]

I am grinding paint off my deck with 24 grit on an angle grinder. It's still a ton of work.

[Captain Smollett]

PS: I use 80 grit to rough up if I am painting over. 100 would probably do if the old stuff in reasonable shape, but for removing...40 or better. At least that's what what I am up to.

[CharlieJ]

Are we talking topsides or decks here?

Sure as the devil wouldn't touch our topsides with 80 grit !!!!  Maybe 180, but nothing coarser. We'd more likely start with 220.

On the other hand- if we are talking decks, and removing old nonskid for instance, then 80 might be the choice. Just for generalsanding I'd start with 100 though

[Tim]

I agree with CJ, don't use anything coarser than you need. There may be cases (non-skid etc.) where the build-up is great, but typically I go 150/180 to 220.

[Captain Smollett]

And let me clarify that I WAS talking deck, mostly treated with nonskid, not hull topsides.

The only reason I chimed in was because he mentioned complete removal of the paint, which happens to be what I have been doing this week on the deck.  Hard work, even with 24 grit at 11,000 rpms.

In my case, the paint had totally failed, but the primer was bound pretty hard to the under layer.  I'm guessing the paint was not compatible with the primer that was used, or something.

I tried 100 grit on my job, and I'd be working a month or more at the rate it was cutting.   

[CharlieJ]

I knew you were talking deck. Just freaked me to see anyone talking 80 grit for TOPSIDES.

Long time ago I was working in a boatyard in Fl. Guy hired someone to paint his topsides. The dude showed with a disc grinder and 100 grit. He had half the hull sanded before he was caught and run out of the yard. Cost the boat owner about 3 G's to get the damage repaired and then he had the charges to paint the boat still. Yikes!! So it frightens me to see comments about topsides like this.

Of course, as in your repairs you use what you must to get the job done.

[tomwatt]

Sure am glad for the clarification... it caused me to go back to the sandpaper aisle and relook, wondering huh?
I'm fondest of the waterproof sandpapers in 400 to 600 grit, especially for finishing out a surface, and 80 grit looks like gravel to me.
On theother extreme, I have used 0 grit floor-sanding paper before... it really does look like gravel stuck to the paper. But it will take a finish (and excess material) off in a hurry!

[JWalker]

Yes this is for TOPSIDES

the PO had painted it with yachtpaint many years ago and its got some deep scratches and some small areas of peeling.

So I'm wanting to take the paint off and prime/paint.

will be using brightsides and apropriate primer.

I read somewhere to use a foam pad on a sander.....and bring a good deal of patience.

Sooo.....120 grit and then 220 and prime? 

[CharlieJ]

As a professional boatbuilder and furniture refinisher my tool of choice would be a Porter-Cable 7335 random orbit sander, with stik-it discs. Expensive tool but ours is still running strong afte 18 years. Worth the money in my book.

[JWalker]

and you would stick what grit to it Charlie?




OOOOOoooooorrrrrrrrr



should I look at the strippers? (I mean the type that comes in a can...not at a can-can)