hobie 16 hull restoration!

Hey everyone,

I bought a 1984ish hobie last year that is in relatively good shape, no leaks or blisters, and was able to sail a full summer without any problems.

Knowing the boat has never been restored or painted I decided that I should do that this spring to protect and preserve the hull for a number of good sailing years ahead.

I found this great write up http://hobie16bottomjob.blogspot.com that I have been following to the t but I still have a few questions for my boat specifically.


1. I plan on sanding the whole hull (top and bottom) besides getting a smooth base from sanding how much should I go down? What depth scratches should I fill rather than sand? Im guessing light scratches I can sand and any that are a little darker in the cut I should bevel the edges and fill.

2. I worry a lot about 'soft spots' and don't know exactly how to identify them. I have not come across any spots that are uniquely soft but I do notice some play in the sides of the hull over a large area Is that natural? How can I better identify these? I don't see any layer delimitation.

3. I have some hairline cracks on the 'rub rails' on the outside of each hull. How do I correctly fix these. I was thinking about taking a triangle scraper and digging out the holes as much as I can, hopefully below the initial crack, then use some formula 27 to fill.

4. I have one spot on the top and bottom seam of the rub rail (visible when the boat is upside down) where the seam has delaminated. It's about 4 in long but I'm definitely worried about this being a week spot and cracking more. Do I dig out and fill with epoxy or resin, or sand down to fiberglass on both sides (8in or so length wise), create a U shape wrap of fiberglass and build up layers?

5. Last question I promise. I have some beach landing scrapping on the bottom of both hulls. It's to the point where the gel coat has worn away but looks like the fiberglass is unharmed. In the blog he goes ahead sands down and re glasses the strip that was uncovered. Is there any reason I should do all of this? Should I add a single layer? Should I just gel coat?


Pictures to come!

Thanks so much for your time and helping me with my project! Sailing the majority of my life on a bunch of different boats large and small I have never had as much fun as sailing a hobie. Which is why I want to make sure I can keep it for as long as it floats.


Tadd

the bottom scraping of the hull past the gelcoat down to fiberglass.


here is the delimitation point under the rub rail where the top and bottom of the hull meet.


here are the 'spider cracks' in the rub rail, theres unfortunately a bunch.

I have plenty of time to work on this a do it right. I just want to make sure I actually am doing it right so I can do this once and have a great boat.

Thanks again for your help.

Tadd

The seam splitting fix is pretty easy, especially since you have already flipped the boat over. We did this repair to my dad's 14 last year. There was a very long section of the seam on one of his hulls that was separated / had voids. The voids were just filled with silicone (either from the factory or the previous owner). Anyway, we scraped out all the silicone with a small flat blade screw driver. Then we spread the seam apart and cleaned it with acetone and roughed it up was much as possible. Then we filled the gap with West Systems Six10 thickened epoxy. The Six10 was very easy to use since it is self-mixing and can be applied using a caulk dispenser. Then we clamped the seam back together using spring clamps, wiped off any excess epoxy, and let it cure - good to go.

The soft sides on your hulls would be a bit of a concern. The hulls will always have some degree of "give" to them, but if you feel a new boat, the sides are very rigid. If you can flex the sides of the hulls significantly then it means the composite is breaking down. It doesn't necessarily mean the hull is going to fail tomorrow, but things are starting to head down that road. I'm actually in the process of restoring an old set of H18 hulls (same vintage as your boat) that are a bit more flexible than I'd like. I'm adding support stringers to the insides of the hulls. It is a pretty involved project though, not a simple fix.

Personally, I would not re-paint the boat. There are a lot of discussions on the subject already. Usually, you can restore the existing gelcoat quite nicely by using some of the many available polishes and waxes that are readily available plus a lot of elbow grease.

For the hairline cracks on the edge of the hull, you can scrape them out using a can opener and fill with gelcoat, but they will probably return. The problem is that since the gelcoat is not reinforced, as the flange flexes, the gelcoat just cracks. These cracks are very common on older (and some newer) boats.

sm

sanded faired and ready for paint

5 coats of gel coat later.

wet sanding 800,1000,1200 followed by compounding and waxing left.