Sunfish Hull Repair

Thread starter #1
below is a link to a video of a hull repair i made.

i had purchased my second sunfish - a circa 1972 complete fish - in a garage sale up the street, took it out the following weekend only to discover a cheap repair masked a split in the hull at the keel under the cockpit

after having it unprofessionally fixed by a purported fiberglass guy it re-split on the next time out (so much for trying to save a buck)

so i took it upon myself to watch a bazzillion youtube vidoes and read as much as i could on manufacturers websites on fiberglass repair before i attempted the work myself.

i'm sure there are better method to do what i did in some particular areas, but if you are a novice at this stuff like i am (or if i may be bold, was), don't be deterred its not so hard and mistakes can be fixed throughout the process.

my process is documented here:

(for the record - cutting the video took more time than repairing the boat - next time - a few simple pics with a narrative!)
douglas - that was awesome! the video is a great presentation with good narration, too, of how to do the repair (and makes it seem more simple than I had feared). very well done, and the finished result looks absolutely great!
Thread starter #5
thanks guys for your compliments, they are much appreciated. one thing i did leave out was duration and prep work - you basically can count a day for every time something had to dry before you could do the next step, then you triple or quadruple that based on getting derailed by real life due to nights or weekends that you cant work because of obligations (or sailing your other boat!) if your a grown up with a day job, it only gives you a couple hours a night to work. one of the keys is preparation - i bought all of the supplies over a period of weeks prior to attempting anything. i usually set up all my materials the night before a step since i was working between 9p and 10:30 to 11p each night and couldn't run to home depot or a marine shop in a pinch. i highly recommend trying it if you are so inclined - very rewarding!


Well-Known Member
Two questions: :)

How much space (or material) is there between the inside—where one's feet would go—and the outside of the keel area that you very-successfully repaired?

Since you waited overnight anyway, why not use a slow catalyst to get things into alignment?
Thread starter #7
there's about 2 inches clear from the hull to the cockpit and maybe another 3/4's of an inch at the keel - i had to cut the jigsaw blade to keep it from hitting the cockpit. there is no material in that space

regarding the catalyst - the stuff is not cheap and i was only going to buy one hardener so i picked 205. in retrospect 206 or 207 would have given me better for pot life, but i really didn't need it for a relatively small area. plus i may have done a thing or two within 8-10 hrs on a weekend - but i can't recall i'd have to look at the timestamp on the source tape. and it is nice to have that fast-cure option on a weekend when you'd like to make a lot of progress.
where did you purchase the fiberglass supplies? care to share a basic shopping list, maybe even approximate prices if you're feeling generous? I'd like to redo some horrendous patchwork from my boats previous owner, but am worried about the cost of supplies and have no idea where to get them.
where did you purchase the fiberglass supplies? care to share a basic shopping list, maybe even approximate prices if you're feeling generous? I'd like to redo some horrendous patchwork from my boats previous owner, but am worried about the cost of supplies and have no idea where to get them.
I second that - would love to get more specifics on what you bought, liked, didn't like, etc.
Thread starter #10
lemme see... 6oz fiberglass cloth, west systems epoxy 105 and hardener (206 was it?) , west system pumps - a must for ease of mix proportion, west systems colloidal scilica, and west systems structural fairing filler; a pack of squeegees, sharpie, scissors, a box of 100 latex gloves, a sanding attachment for my drill, a cheap palm sander from northern tools, a cheap jigsaw from northern tools and blades, small hand saw and blades, release fabric, sandpaper - 40,60,80,100 and 150 grit for dry sanding, and 300 and 600 for wetsanding; bottom paint ( i actually used behrs garage floor paint after a recommendation i found in some old threads in this forum) masking tape, exacto, a half dozen small and large rollers, a pack of various small and large foam brushes, white pigment for expoxy, tack cloth, box of paint rags, masking tape, screws, fishing line (screws + fishing line to the rafters is a good way to press you backing mould to surrounding area,) visqueen, acetone (prep for fiberglass), detnatured alcohol (prep for painting), box of stir sticks, multiple plastic cups for mixing epoxy and fillers. I think thats it.

Fiberglass related items came from local a marine store that undercuts West Marine by a few bucks, tools were from northern tools (probably could have saved a few bucks at harbor frieght,) general supplies came from home depot which were cheaper than the marine store.

$ from memory - i could be slightly off:
I think it was about $90-100 for the west system supplies and fiberglass.
Maybe $15 for the bag of cloth
$6 or $7 for the squeegees
$10 for the latex gloves
$5 for the sanding attachment
$15 for the palm sander (did not have one)
$30 for the Jigsaw and blades (did not have one)
$10 for the hand saw and blades
$15 for release fabric
$35 in misc sandpaper
$25 for 1 gal of bottom paint (in lieu real bottom paint for almost $200 plus it covered two hulls)
$5 for masking tape
$5 for exacto and blades
$25 for rollers and brushes
$15 for white pigment (i seem to recall it being particularly expensive)
$6 for tack cloth
$12 for a box of paint rags
$10 for a few rolls of masking tape
$7 for stir sticks (got them from beauty supply for leg waxing)
$9 for visqueen
$15 or so in miscelleneous plastic cups
$10 for acetone
$10 for dentatured alcohol

Adds up to about $400 (ouch!)- with enough surplus to do it twice or more.
Wow thanks for the very complete list. It's helpful because I'd be starting a projec like this in the same place tool-wise as you. It's amazing how much the little stuff adds up.
Douglas - fantastic video. I have a couple of questions before I attempt the same repair.

1 - dumb question, visqueen is just polyethylene plastic, right?
2 - which fairing filler did you use, 404 or 407?
3 - what has your luck been with the behr garage floor paint as bottom paint?

You made it look pretty straight forward. Great job!
Thread starter #14
shoreline - thanks for the compliment:

1. yes - visqueen is polyethelene
2. 404 - i figured it would add tothe structural integrity
3. the garage floor paint has holds up pretty well - there are a few nicks an scratches: i land on mossy coral rock at low tide at my launching/landing point, and there is some thinning at the place where the hull rests on the trailer bunks, but all-in-all the savings ($25 vs $175) is worth it.