Chance,

I went thru what you're doing a few years ago. Had the boat soda blasted and it left the surface pretty rough, going all the way thru the gel coat in a few places, quite a bit rougher that what you're getting. The pressure washer eliminates the need for building a tent under the boat to capture all the debris and greatly improves visibility, which I think makes a big difference in the final surface finish. Here's a link to the post I did on it including some slide shows showing the soda blasting, priming, filling, sanding, filling, sanding, etc. http://www.classicseacraft.com/commu...inting+project I'm sure the final Interprotect thickness is less than optimum for blister protection, but I wasn't worried about that because I never leave the boat in water for more than a couple weeks at a time. The Signature paint has worked out very well. It's tough stuff, very easy to apply, and it's easily repairable, which is important for a trailerable boat because a few random nicks and scratches are almost inevitable.

I see you have a roller trailer, so it should be easy to pull out from under the boat as you put some boat stands under it for easier access for sanding and painting. If you can't find boat stands, it's easy to make up some pyramid type stands like the soda blasting place had using a few 2x4's. Suggest you totally refinish the spots where you'll put the support stands before pulling the trailer, as that will save a lot of time later. Hope this helps. Denny

Wow. That does help Denny. Thanks

Looks like maybe there were some voids in the layup between the gelcoat layer and the glass layer.
The gelcoat gets sprayed in the mold and then when the glass gets layed on top sometimes it can be tricky to get the glass to lay up right against all the gelcoat.
Especially in the nooks and crannies, like those chines. So you end up with a little bubble between the gelcoat and the glass.
The gelcoat is super thin and has no real strength of it's own so it eventually just kind of "pops" exposing the bubble.
It happens. You still see it on newer boats too.

No real harm there. I'd fill it and fair it though.

thanks Zak, i read somewhere that 6-10 epoxy is good for filling those kind of voids. Does that sound right? Thanks.

6-10 is handy stuff and good for filling screw holes, etc, but it's expensive! I used the Fasco Fas-stone #7 Epoxy http://www.fascoepoxies.com/products.html that Capt. Chuck recommended for ALL the filling and fairing work. It's very strong but about the same hardness as gel coat, so it sands great and the 50/50 resin/hardener mixture makes it real easy to use! I got a quart of it (1 pint cans of resin + hardner) and it was more than enough to do the whole bottom of my 20. I think you can buy a whole quart of it for about what you'd spend for one tube of 6-10!

I feel your pain
 

I am going through this right now on a 1969 Formula 233. Try easy off oven cleaner, then power wash. I used about 5 cans, and 3 pressure washings, it did not take all the paint off but took off a few layers that made sanding it much easier. The only place that it did not make much difference was towards the bow where I assume the bottom paint was dry most of the time when the boat was in use and was therefore much harder. I finished removing all he paint on the port side. The oven cleaner also took a bunch of the boot stripe off. I think if it was warmer the oven cleaner would have worked much better. I also tried interstrip and another nasty chemical stripper from the hardware store but I think honestly the oven cleaner worked best. When it came down to it, about 50, 80grit sanding discs and 3 days of sanding worked best. If you want check out my results, the bottom paint removal is at the end. I also have those nasty air pockets on the chine. I was going to use the interlux watertite to fill the dings but now I want to look into that 6 10 http://www.thehulltruth.com/boating-...storation.html

Pretty much any epoxy would be fine for filling those voids.
But because it's below the waterline, make sure it's not thickened with micro-balloons like System Three Quik-Fair or Interlux Interfill, etc. etc. (unless you're going to coat the bottom with epoxy primer)

You could mix up your own filler with a little West System 105 Resin and 205 Hardener and some colloidial silica (cabosil) or other high density structural adhesive filler.
Make it thick enough so it wont run, but not so thick that you cant work it. The thicker it gets the faster it'll kick too. Usually when your trying to trowel it on. :-P

Well, the weather was decent today (40 degrees) so I decided to bite the bullet and sand the bottom after trying many different methods to removing the bottom paint. Only took 4 hours to do the port side. One guy, one orbital sander and two numb arms.

This is what the port side looked like too (I didn't get any before shots). Then how it turned out. Next week I'll do the other side than pull it off the trailer to get the rest unless I can get my hands on some boat stands sooner.

http://i1326.photobucket.com/albums/...pse374b9f1.jpg

http://i1326.photobucket.com/albums/...ps5b8e653c.jpg

Damn, I can't imagine what a bitch that was with the boat being on the trailer. I still have 2 little spots to do where the keel blocks were before I moved them. I keep putting it off. I got a good deal on some 3M marine filler. It's vinylester based, found a gallon on amazon for $79 I think. What are you planning on doing to the bottom after you get the paint off? Home depot in hyannis has diablo sanding discs that are reasonably priced.

Yeah it was a pain in the butt, but it wanted to start this before it got to warm and I don't have any stands. I have many many gel coat failure ares that need to be addresed than a few layers of hard bottom paint. Maybe roll on some gel coat, I don't know, I've never worked with it. What would everyone recommend. It stays on a trailer and I have a limited budget. Spraying any paint or gel coat is not an option. Man hours I have...

My opinion is to roll on some gel coat. You can't see most of what you will be doing when it is in the water, and you will likely bottom paint it anyway. The only place where smooth counts is the planing surface, and that's if you care and had a smooth surface before to compare to.



Gel coat is also relatively safe in terms of accidental exposure to wet material. It smells, but isn't poisonous like urethane paint or a sensitizer like epoxy.

Hermco mentioned the 3M vinylester below waterline marine filler if you need it. Or Mertons has hull and deck putty in polyester. I haven't used either, but just bought the filler from Mertons- just before I heard about the 3M from Hermco.

Cant I just roll and tip the gel coat than wet sand to polish without having to paint it after?

After i fill the dings in mine with the 3m i am going to put interprotect 2000 i think its under $100 a gallon. According to a guy at jamestown it isn't shiny but it can be left as is or painted over with whatever you want.

My opinion- I don't see why not. Gel coat worked for the first 40 years, and I would/ will repair reapply gel coat when I need to.


Mine already have bottom paint, and it looks ugly. Right now, they are trailered boats, so if I were to do what you were doing, I would finish with gel coat and stop there. I would sand it flat, but I don't think I would wet sand mine. I get too little time off work to spend it anywhere but in the boat on the water, not under the boat, if I can possibly avoid it.

I would highly recommend Signature Finish paint instead of gel coat, which I'm not sure you can apply over the Interprotect epoxy anyway. It's not porous like gel coat and much tougher, and one of the few urethane paints that will hold up under water. It's safe to roll & tip outdoors with a good NIOSH respirator. Mine came out fairly smooth and glossy just using a foam roller. It's also easy to mix up small quantities for touch up using small plastic syringes to get the exact mix of paint/thinner/catalyst.

Great advice everyone. I'll get a picture later but I literally have hundreds of dings in the fiberglass on the bottom that are now visible after removing 40 years of paint. I don't have the hundreds of hours it would take to grind them all out to the 12:1 ratio and fill with glass sand fair sand fair etc... Is it okay if I Clean em up with a dremel, clean, than use six 10 to fill and fair them?

These are the chips in the fiberglass I'm talking about. Everyone one of them are on the hull steps the length of the hull. Now what's the best way to fix em?

http://i1326.photobucket.com/albums/...ps79e56e54.jpg

Chance, that white Fasco epoxy I recommended earlier in post #45 would work well on those dings. I had quite a few dings like that. It's less than $30 for a quart and is about the same hardness as gel coat when cured, so it sands real nice. If you look thru the pics of the sanding and fairing slideshow of my bottom painting project in the earlier post, you'll see that I used it all over the bottom to fill nicks, dings and low spots. I put Interprotect over the whole bottom to seal it under the paint, but if you plan to sand Interprotect before painting, do it the next day! It continues to harden and if you wait a week, it'll be like sanding granite! Denny

So I can just grind them out a little bit and fill them than sand before interprotect?

I didn't really do much grinding on the dings and gouges, I just filled 'em, but I suppose some grinding wouldn't hurt. Most of what I had to deal with involved low spots in the gel coat that was fairly porous, so I wasn't too concerned with adhesion. Being epoxy, the Fasco stuff should have good bond strength. It seems to have about the same strength as Marine Tex when cured so it's pretty tough stuff, but it has a thick creamy texture when first mixed, so it spreads real nice. It's been 4 years since I did the bottom; I've run the boat well over 1000 miles since then, some of it in pretty rough stuff, and I've had zero problems with cracks or disbonding of the filler.

Good to know. Thank you for the insight.

I got a few hours of sanding in today. She's coming along. Notice the difference from post #48. Shrink wraps coming off this Tuesday or Wednesday!!!

http://i1326.photobucket.com/albums/...ps11a5d45e.jpg