Preparing old boat for paint
 

I'd like to start prepping for paint. Plan is to paint everything from the chines up (except transom which is already done). Everything has been removed so it's ready.

The boat was previously painted and I don't with what. The paint has been there for at least 5 years and sticking pretty good. First question is do I 'need' to sand it back to the original gel? I hope not because I don't see that happening. Next question is where to start?? The boat is not flat. Some of it I have to live with, but some I'd like to straighten as much as possible. What I was thinking to do is spray it all over with a rattle can and then use my 36" flat board with like 40 grit? This way I can really see the peaks and valleys... and most important, hire a kid or day laborer to stand there and sand all day.

No need to remove old paint unless its falling off. I would start blocking with 220 grit and no less than a 36" board. It would be very easy to hire day labor but you will have to keep an eye on them. Rattle can "guide coat" will help if you don't know what to look for. You will need to finish sand with 600 grit before you seal and paint. Anything less will give you sanding scratches in new paint

If you feel the paint that is on there is stuck pretty good no need to remove it. You can actually use it like a primer and do a bit of fairing with it. Hate to say it but as the owner of the same hull i doubt long boarding is going to do much on its own. The problem is that most of the non straight areas are the result of long hollows and just the natural way those boats cured in the mold. I would probably do just what you were saying with black rattle can lacquer primer as a tracer and go after as much of the details as you can. I usually break it down with 180 for heavy leveling then step to 240 and up to 320. I never go past 320 for solid colors or single stage paints and use a short orbit finish DA, i also tend to use disks longer and they break down to about 400 grit level. Unless your shooting metallics or pearls no need to go finer. Spot repair and prime anything that doesnt sand out, What color is the boat now and what color is it going to be?

Wow thanks guys! glad i didn't start whacking it down with 40 grit lol!

Here are a couple start pics. Side3 shows waves, i have to live with those. Side4 shows lumps. This is from a crappy prep job the previous painter did. It had bottom paint and you can see pretty clearly where it was. In side5 you can see my makeshift sanding board up on the fairing (which I'm still working on) It's aluminum C-channel I put a couple handles on. I also have a 12" flexible sanding board i use for the curves.

So what I will do now is get some 180 grit, lay down a tracer coat and hit it by hand. I'll post some more pics as I make progress.

I have a gallon of snow white awlcraft 2000. I also have a matching quart of PPG DCC Concept I planned to use for the dash. I don't know why I planned that. They are both acrylic urethane. The boat now is more like a grayish/white compared to snow white.

you can see the lumps from the reflection of the roof line (middle pic)

yep . . . looks just like mine :D

i use DDC on boats that i am painting just white with no graphics. Great stuff and looks awesome when buffed. My signature color is 91050 and works well with all colors. Its a very clean white but not overly bright. I sometimes use an 8 inch gear drive DA when leveling big stuff and knocking down paint thickness.

Ok, so I went and put down a guide coat. probably too much but I get the idea now. I tried sanding with my long board and couldn't. This place is like really concave, with the high spots being the transom and the bulkhead. So I had to change to the 12" flatboard. I'll be happy with the outcome if I can just get it smooth.

The guide coat after sanding pic is real. all that dark is just plain disgusting prep work from the previous owner. I think they tried using a metal grinder... even a belt sander would have done a better job. Some of the dark spots are actually down to the original glass... it's bad.

So my first instinct is to stop here and lay down a layer of fairing compound. The rest of the boat is fairly straight, it's only where the bottom paint used to be that's real bad.

yikes that does look pretty rough. Dueatec makes a great sprayable fairing primer that fills great and sands easy its called Duratec VE but its only for use on ester surfaces. If those ruff spots are isolated to just those areas may be better to just pull on a couple coats of filler.

i would rather use to much gude coat then not enough, that looks fine.

Thanks Dave! by filler do you mean the 865 final fair? For these places I plan to fair, can I back down to 80 grit first? Forward of this mess it's fairly straight (except for the windscreen)