Repair Advice

P Sib

New Member
Bought a cheap Sunfish as a first boat in need of quite a bit of repair. Figured it would be a good winter project in the South. Pretty heavy, have started drying it out via two inspection ports and a four inch duct fan from a project that never worked out (pretty much an enclosed litter box that vented the litter smell to the outside.) After washing it, however, I've started to take stock of the gouges and scrapes that it has. I'm fully prepared to go ahead and patch as much as it needs, keeping in mind that I'll probably have to fix some of the "repairs" that have already been made.

Here are photos of the three places I'm most concerned about. I didn't notice any leaks (soap bubbles), but may be concerned about any seeps that may let some water in slowly. Right now, I'm wondering if these will need to be patched with fiberglass or if I'm good to use a filling compound.
 

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Bought a cheap Sunfish as a first boat in need of quite a bit of repair. Figured it would be a good winter project in the South. Pretty heavy, have started drying it out via two inspection ports and a four inch duct fan from a project that never worked out (pretty much an enclosed litter box that vented the litter smell to the outside.) After washing it, however, I've started to take stock of the gouges and scrapes that it has. I'm fully prepared to go ahead and patch as much as it needs, keeping in mind that I'll probably have to fix some of the "repairs" that have already been made.

Here are photos of the three places I'm most concerned about. I didn't notice any leaks (soap bubbles), but may be concerned about any seeps that may let some water in slowly. Right now, I'm wondering if these will need to be patched with fiberglass or if I'm good to use a filling compound.

Dear P Sib

You're going to have to clean all these places up before you could determine repair needs. Wouldn't worry so much about the ding on the transom - since it should be out of the water most of the time - but the other two places have some significant damage. Start sanding and see where it takes you! Where are you located?

Cheers, and welcome to the asylum,
AQBill
 
I'd remove the old repairs. They are probably of polyester resin, so they can be scraped off using a $12 heat-gun and putty knife. Sand, as suggested above.

The strongest part of a Sunfish is at the bow, so damage there should be addressed. I'd cut the damaged part out, repair it from the backside, and use the "Shoreline" method to put it back in. Allow a 2-inch margin, so all the impacted area can be reinforced.

For a view of general Sunfish fiberglass repairing, peruse this comprehensive Sunfish Talk thread:
Starting at the BEGINNING | SailingForums.com
 
Thanks everyone, went ahead and got the old patch removed and it revealed about half a dozen small plugs, about 3/8" each. Two are blowing air through. I was wondering which technique is the best way to go about fixing these
 

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First, I'd prepare the openings that you can see.

Grind a quarter-dollar sized area around each hole. Take a large drill bit (or a countersink) and taper the edges. Take a 1/4" flat punch, and knock out (don't drill-out) the existing plugs. (That'll prepare—somewhat—the side you can't see). We're trying to make a large fiberglass rivet (however offset and irregular it may become). ;)

Prepare a small amount of Thixo ($24 at hardware stores) and find a nail with a head that'll "clear" the hole. (Or grind a roofing nail to an offset "L" configuration). Using the nail, spread the mixed Thixo inside as much as possible, and allow any extra to (temporarily/clumsily) seal the hole. Allow to set, then sand what remains, so it's not shiny. Add a little more Thixo and cover with a clear, and relatively firm, plastic film such as found on ice cream (Breyers) or margarine tubs. Smooth the film flat over the new Thixo layer, so it's only slightly "proud" of the surface. Some sanding may be necessary before painting. (Spray paint will show small imperfections, whereas a brushed paint should cover all the repair well).

Thixo is a prepared resin-mix ideal for small holes or small cuts in Sunfish. West Systems makes a comparable cartridge in it$ 6-Ten product, available at West Marine stores. Realizing this may be a bigger project than intended | SailingForums.com

Krylon spray paint makes a white color that is "warmer" than Rustoleum's [appliance] white, and matches Sunfish's "white" hulls better.
 
I have the glass and resin on hand so I would use by 5" DA sander (a Makita) to sand a taper around each of the holes. While doing this I would make sure the glass was not separated. Then just lay about 4-5 layers of glass around it. I start large, that is covering the whole sanded area and then go smaller. Wet out the glass and the area around it. You want the glass wet out, but not dripping. Then lay the glass over the holes. Sand then gel coat. Done.

The alternate way would be to get marine tex epoxy. You might also need some thickener. Do the same sanding and then cover with the marine tex. I am not sure if normal marine tex with try to drip into the hole, depends on the size.

To do a poly resin repair you would need to get a qt of resin, a quart of gel coat (without wax is my preference), some glass cloth, some disposible brushes and small mixing cups. You would have to buy a lot. On the other hand, you are likely to need to do other minor repairs as you use the boat. Once you get used to doing the glass work it is pretty quick and easy to do. Having the 5" da makes it go faster. You will need 80 grit for the initial tapering. Then 180 and 220 to smooth out stuff.

Marine tex is one and done. But it stands out more then a decent gel coat repair.

You have options. Go watch videos and look up costs and think about how you want the boat to look like when done. Then make informed decisions. I needed to do some major work so I bought a bunch of what I needed. Over the summer I did some quick fixes with the marine tex and saw how well it held up long term. Basically with marine tex you need to do the same sanding and feathering to get a good bond. Over time the marine tex yellows and stands out. But it works when done right.

I have only used the thixo for bonding the deck to the hull. It would likely work. Again how it works is directly related to how well you get a bond to the base. You can also use both marine tex and thixo with glass cloth to help get over the holes.

If you have a boating community local to you reach out and ask if someone will help you do the repairs. If they are like me they will look at how little needs to be done and do it with stuff they have laying around, or I should say show you how you can do it and let you do the work.
 
To edit my quick/inexpensive technique:

1) Thixo is a strong epoxy resin, bound with a small amount of thickening agent. These cartridges contain a 3-inch plastic plug, so it is not particularly an abundant source of epoxy. (Just FYI). :oops:

2) My described repair (above) is only for the six 3/8-inch hull holes near the transom, as described by the OP.

3) Consider every drilled hole in fiberglass Sunfish as weakening the material around it. :(

4) Stored, and exposed to sunlight, MarineTex applications will yellow.

BTW: I've rescued another Sunfish--a 1971 "transitional model". (My 7th Sunfish in as many years).

Stored as it was--and unable to inspect it--I'd intended to make a "donor" Sunfish out of it...but it turned out to be in better condition than the 1979 Hurricane Irma Sunfish that I've nearly finished refurbishing--given to me by a neighbor two years ago! :rolleyes:

'Will trade this hull for an earlier, not-restorable Sunfish hull within Florida ZIP-codes 33852 through 33042.


But to get this new-to-me Sunfish back on the water, donations of mast, board, rudder, and spars would be appreciated. ;)
 

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