what sandpaper to use

[bassmaster8100]

Im redoing a fiberglass boat. Im not sure what sandpaper to use to sand it with, plan on repainting it. A couple of years ago I wet sanded it and recleared but it didnt hold up its now starting to flake off. I want to paint top and bottom side. Dont wanna mess up my hull or anything , any suggestions on what to sand it with??? Also is it ok to use automotive paint or should I find someone who sells some kind of marine paint???????

[bassmaster8100]

Can anyone help????????????????????????????????

[Way2slow]

If you're going to spray paint it, you will have to do a final wet sand with about 400 grit. Automotive paints don't hide scratches, no matter how small. If you sand with anything larger than 320 grit, you will probably see sanding scratches.

None of your automotive paints are going to stay on gel coat. They will chip easily and once it gets a chip, the chip will keep growing. I stick by the rule, if your going to sell a boat, paint it. If you're going to keep a boat gel coat it. Now, even recoating it with gel coat, the gel coat will even peel if you get lifted but won't chip and flake like paints. If you've never worked with gel coat, you don't want to learn by doing a whole boat for starters you will be bitting off a whole lot more than you're gonna wanna chew.

There are some guys on Scream and Fly that do a lot of fancy painting of boats and could probably give you good pointers on what's the best way to chase that rabit and the best products to use.

[bassmaster8100]

I had started out with some 320 but didnt seem coarse enough to me, I dunno. The clear coat is flaking off and I figure Ive got to at least sand the clear coat off. I want to fill in some holes and all where the guy that had it before me had like some rod holders and all but I didnt need that crap because all I do is bass fish. I was gonna use like some filler primer whenever I got it down but I dunno. I know if I get too close to the fiberglass tho Im gonna find alot of little pits and imperfections in that fiberglass hull. ????????????????????????????????????????????????????

[Low_Budget_Hooker]

Look into a full system from interlux paints.

[bassmaster8100]

Im gonna have to check into that interlux paint, thanks for the suggestion. I talked to a guy I work with I knew painted cars and he recommended 180 grit sandpaper. The old clearcoat was flaking and I knew I had to cut threw it or whatever I put on it was just gonna flake off as well. I finished sanding it with the 180 today worked out great. Few screw holes and all I wanna fill in now and then itll be time to prime and paint, Im gonna check into that interlux paint. Where is the best place to buy interlux paints?

[tritonman]

I would use 1200 to 1500 sandpaper for fiberglass if you are looking at a fine finish. You can also use this on the gelcoat once you are done painting.

[Way2slow]

If you're wanting to remove the old gel, you will probably want to start with 120 work up from there.  That gel is going to be a lot harder to sand than your average auto point.  I also think you're opening a can of worms you might have a hard time closing if you start trying to do some heavy sanding on that gel, if the top coat is gel.  From what you are describing about the clear coat flaking off, I seriously doubt you are dealing with gel on the top coat and if it's not gel, it all realy needs to come off to get down to the original gel for anything you spray back on it to even have a chance at holding up.  

I just hope you love this boat because by the time you get done, if you do it right, you are going to have a hellava lot of hard work and more than just a few bucks invested in it.

There is another product I hear people say works very good on fiberglass and gel coat called AwlGrip, but I have never used it.  

[Bass Smacker]

This is what I did. Paint /clear coat will not stick to fiberglass. Automotive primer will and paint will stick to primer. But it will be soft and scratch. Unlike gel coat it will not hold up.

I used just reguler sand paper start cors and work to fine

     

[bassmaster8100]

Im not sanding down deep enough to get into the gel coat, I was talking with a friend of mine last night , I had forgotten he used to work at a boat manufacturer, so here the deal uve got that fiberglass hull , u gel coat it, then u use etching primer, and then of course you put ur marine paint on top of that, he tells me that what Ive sanded it with (180) all i need to do is prime and paint that i havent cut deep enough to effect the gel coat.

[mudcatwilly]

I did a whole paint job on a fiberglass boat about 2 months ago.  Here's what I did:

1.  Take off old decals using a combination of acetone, a heat gun, and elbow grease.  I had to remove two 8-inch wide decals that ran the length of the boat.  The heat gun was the only thing that would take those things off.  Acetone helped get some of the old glue off and sanding took the rest off.

2.  Once the decals are gone, buy a random orbital sander.  It's worth it's weight in gold just for this project.

3.  I took off the "shine" of the gelcoat using 60 grit paper on the sander.  The hard to reach areas were sanded by hand.  Be careful not to sand all the way down to the fiberglass.  You just want to dull the finish.

4.  I then filled all the little cracks, gouges, screw holes, etc. with 3M marine filler.  It's basically a 2-part epoxy.  Use a little bit at a time and work fast.  It sets up quick.

5.  Sand down the epoxied areas with the 60 grit and do any touch up with the epoxy if needed, then sand the patch again.

6.  Sand the whole boat down once with 120 grit, then sand it down again with 180 grit (or finer if you like).  For me, I'm not such a great painter that you could tell the difference between a 180 or 320 grit paper.

7.  Wipe the boat down thoroughly with a tack cloth and then go over it with a clean rag soaked in acetone.  Repeat if necessary.  You don't want any dust on the boat.

8.  I used 3 coats of interlux brightside paint.  This is topside paint that I used on the topside and bottom of the boat.  You can use the topside paint on the bottom as long as you don't store your boat in the water.

[T_Dot]

saftey first

do you have gloves, a mask and a suit?

[bassmaster8100]

got the safety thing covered

[FIN-S-R]

Aircraft paint...its tough stuff. Did a ski rig in black...figured out along the way that the most important step is sanding. The quality of your sanding job will dictate the quality of the finish...unless your doing white and then it doesnt matter as much. Wipe the boat down good, and then wipe it down better before your shoot it.

[bassmaster8100]

The color that Im actually doing is navy blue on the bottom side with yellow top side and blue carpet