1970 Sunfish Repair - Needing help to bringing order to the chaos!

You have a Folboat? Awesome! Would love to see a photo or two. Those are great examples of engineering.
I also have a blue Folbot (wood frame). This green and yellow (metal-framed) Folbot came with a complete sail kit: A tower of power with 45 square feet of sail. :rolleyes:

As you can see, it's a long reach to bolt on a bow handle! :(
 

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The pin is held in place because the carriage bolt is tightened, spring tension on the spring plate pulls up on the latch plate and vertical hinge plate, which traps the rudder pin between the vertical hinge plate and horizontal hinge plate. So it doesn't really matter if the swivel tang straightens. There is also a little tension on the swivel part.
 
"...Rivet nuts (rivnuts) were used back then with marine grade stainless machine screws, but a rivnut gun and rivets will run you about $150+.
"Riv-nut" pictured to the far left in the photo below.

I might have the "proper" rivnut stored elsewhere, but it occurred to me that the special rivetnut "gun" is not essential.

While it's a slower process, adding a washer, threaded nut, and long, threaded bolt could save the day...
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Light and Variable, I have to say, we think alike when it comes to finding a way to make it work. We call that red-necking-it down here.
 
I'm having a little panic attack. After an aggressive hull cleaning, the subtle defects in the gel coat are more obvious. In particular, as I prepped an area for Marine-tex at the transition between the hull bottom and the gunwale I noticed not only these horizontal hairline cracks, but a consistent distribution of tiny pores in the gelcoat toward the waterline. They are irregularly distributed all around the gunwale.

Did I create these pores from my bleach cleaning? Is there a filling compound I should consider, or JUST FORGET ABOUT IT!

Help!

Gelcoat Pores at Gunwale.JPG
 
Here are all the mahogany component hanging with their first coat of spar varnish. The long skinny thing is our replacement tiller extension we made out of... white oak, of course. My son thought it was supposed to be ash. We stained it "Red Oak" to make it colored more like the mahogany, but I rubbed off some coloration only to notice later the sealed mahogany darkened more. I should have kept it "Red Oak" full strength.
I believe I read somewhere that they need 8 coats? Is this true? I know they need to be as tough and waterproof as possible. 8 coats?

Spar Varnish Process.JPG


I noticed a few interesting features after the sanding.
Damaged screw hole in the dagger board. I planned on building a masking tape dam on each side and filling the void with two-part epoxy, maybe filled with glass fibers.

Good idea?

Dagerboard Screw Damage.jpg


What is this metal thing in the rudder hinge area? Probably intended for strengthening. It appears to be steel. Is this OEM or aftermarket?

Rudder Reinforcement.jpg


Should I try this to reinforce this crack in the rudder/tiller bolt hole area in the same way as above mentioned method?

Cracked Rudder.jpg


And what is this little black sticker on the tiller near the joint for the extension? OEM or aftermarket? Do I need to put it back?

Tiller With Black Sticker.jpg
 
1) Rub some dirt on those gelcoat divots, you won't notice them from a galloping horse. See Problem Solving Matrix #1: Galloping Horse. Can you back up and take a photo of where that area is?

Those pores appear to be defects in the gelcoat, probably came from the factory that way and got bigger through the years. Maybe the mold was not cleaned properly, prepped with release agent or sprayed well. The hairline cracks come with age as gelcoat shrinks faster than the fiberglass underneath. You didn't create them, you just cleaned them out. Probe the area gently with a dull awl or small screwdriver to makes sure there are no soft spots in the fiberglass, I don't expect there would be as impact or stress damage usually has gelcoat cracks radiating out from a point. I'd fill them with something, as the gelcoat is primarily there to protect the fiberglass, from sun and long term water intrusion. Some folks go aggressive and take off an entire area of gelcoat, others would spray or brush on gelcoat and sand it down. Paint could be used or Marine Tex or a fairing compound, and if it were me I'd lightly skim it with a tube of Pettit EZFair and sand it flush.

2. Your Son is right, but on a small piece like an extension the weight gain of oak is negligible. Oak will last longer.

3. We have never thinned stain, but have applied additional coats to darken.

4. 2 is minimum, and usually maximum coats for us. That old daggerboard is probably pretty sealed up from years of varnishing. Go for the finish you like, and if someone else doesn't like it, they don't get to go on the boat. See Problem Solving Matrix #3: If They Don't Like It

5. Yes on the thickened epoxy repair. Or grave in a new bit of wood and fasten it with thickened epoxy....or skip the wood...we're back full circle to thickened epoxy...you see how this boatbuilding decision making thing works?

6. OEM. Drift pin showed up at one point to help prevent grainwise fracture, mostly from folks letting the rudder slam up. A lot of folks pick on the old style rudder for popping loose but at least the blade didn't split chunks off... Hmmm, seems like I'm up too early...but I made a friend selling him a new rudder blade...

7. I'd scrape a small valley in that crack and inject some neat epoxy, shaken, not stirred into that crack, let it soak in, one side at a time. And I like the screw idea, similar to the drift pin. Pilot hole and countersink if you have em.

8. Rubber Baby Buggy Bumper...looks like a rub pad, or remnants of one, to keep the tiller extension machine screw end from scraping a half moon into the deck. One hack is to put the screw head down and nut on top, but if the nut falls off, away the screw goes to. Another hack, make sure the right size bolt is used so no extra threads are exposed.....make sure tiller is set to correct height...the list goes on...
 
Here are all the mahogany component hanging with their first coat of spar varnish. The long skinny thing is our replacement tiller extension we made out of... white oak, of course. My son thought it was supposed to be ash. We stained it "Red Oak" to make it colored more like the mahogany, but I rubbed off some coloration only to notice later the sealed mahogany darkened more. I should have kept it "Red Oak" full strength.
I believe I read somewhere that they need 8 coats? Is this true? I know they need to be as tough and waterproof as possible. 8 coats?

View attachment 43451

I noticed a few interesting features after the sanding.
Damaged screw hole in the dagger board. I planned on building a masking tape dam on each side and filling the void with two-part epoxy, maybe filled with glass fibers.

Good idea?

View attachment 43452

What is this metal thing in the rudder hinge area? Probably intended for strengthening. It appears to be steel. Is this OEM or aftermarket?

View attachment 43453

Should I try this to reinforce this crack in the rudder/tiller bolt hole area in the same way as above mentioned method?

View attachment 43454

And what is this little black sticker on the tiller near the joint for the extension? OEM or aftermarket? Do I need to put it back?

View attachment 43455
The metal thing appears on all of my five Sunfish rudders.

More coats?

You say "spar" varnish, but is it "polyurethane" spar varnish?

You'll need fewer coats with polyurethane. Older varnishes (what I use) could account for the "several coats" you'd been previously advised.

I sand and revarnish with roughly one coat each season. (Adding a few bugs). :confused:

After the above repair, I'd drill a third hole for the daggerboard handle. Sometimes that board can slam down.

...I recall winning a Snipe-class boat race, and then needing a tow back to the beach. :oops:

The daggerboard slammed down and, although the handle suggested nothing was wrong, there was this annoying sloosh-sloshing sound coming from beneath it. Moments later, I realized the metal board had broken free, and had "sailed" to the bottom! :(

I suspect that rudder crack is "working" to relieve the torque in abusive rudder stresses. How many of our mahogany rudders are like that, and still operating well?

Still, that rudder could use a screw reinforcement--as you suggest. The crack could be enlarged slightly with a hacksaw (metal cutting) blade, filled with epoxy--then drilled for a stainless screw.

Not only is there a reoccurring twisting force there, the mahogany is brittle, so select your drill bit size carefully, and go easy on the screw-tightening. You don't want to add stressors in that area.

I'd be tempted to use a thin (3mm) stainless nut and bolt--tapping it gently in--and countersinking both ends minimally. (Or just let it go).

Even small spots and cracks aren't likely to be made invisible with painting. But, being on the bottom, it's not going to show. :rolleyes:
 
There is a slight curvature to the plate that seems to match well to the keel? This is correct or should it be flat? Maybe the CARRIAGE bolt had been over tightened at some point?

I think you guys skipped over this question. Any tips?

Also, what was that black round thing that came with my packet of used parts? See end of page two, please.
 
I learned a lot from my first Marine-Tex experience. I'm a total novice so my difficulty, I'm sure, is no legitimate commentary on the product. Everyone seems to really like the product so I'm not going to waver in my confidence in using it.

1) Really tough to get the putty out of the measuring spoon after scooping.
2) The virgin putty is very sticky so anything that touches it gets the stuff stuck to it.
3) The mixed putty is much easier to work with than the virgin putty, so that made things better.
4) The plastic film trick for smoothing the application did not work for me. It trapped air bubbles and left a rippled surface.
5) The wet trowel idea for smoothing the application did not work for me. I found myself pressing the putty down creating a low place which required a follow-up filling later.
6) I was perfectly content with using a dry putty knife for applying. It stuck to the knife, but I was able to spread what was needed by heaping up more than was needed on the knife. Like trying to put sour cream on the top of your taco.
7) I found the sanding relatively easy starting with 100 grit on a wood block and finishing with 320. It seemed to me to have sheetrock mud response to sanding, except it was easier because the gelcoat around the work was tougher than sheetrock paper. If I had known it was this easy to sand I would have erred on the heavy side for the first application. The mix/apply part was much more stressful to me than sanding because of the unfamiliar set-up speed of the goopy stuff. And sanding I could take my time and sneak up on a feathered edge. I had watched one guy in a popular youtube use the stuff and he was a hack that made it look impossible to sand. It looked like he used an angle grinder and made things worse that when he started. So one concern I have in light of the easy sanding is, is it really so tough?
8) The sanding dust stays put and does not fly around much which made clean-up easy.
9) The finished work is bright white and my hull off-white (maybe it was white 50 years ago - don't know). The white splotches of irregular shape filler made the hidden injury appear like it might be really scary under there. "What kind of structural hole is under there??" (That would be a resale concern.)

1st Puty Application.jpg


After second coat and sanding.

I think I'm done?

Final Marine-Tex.jpg
 
Here is the area where I took the photo of the gelcoat pores. The photo is bottom up. This condition is present on the gunwale more or less all around.
So I did not cause these pores either?

Some delicate vines will leave small pits upon removal of their tiny rooting attachments; however, it would take years and years to do that kind of "damage". Lichens, not so much a concern.

You don't really need to do anything, but rolling on Rustoleum might hide most of it. (Spray paint definitely won't hide it).

If you're unsure of your Marine-Tex finishes, spread a little rubbing alcohol (or just water) to detect any imperfections. In automobile panel repairs, I was advised to spray with gloss-black paint. (Which I did just once). :rolleyes:

Light and Variable, I have to say, we think alike when it comes to finding a way to make it work. We call that red-necking-it down here.
My Wisconsin-bred neighbor, says, "You're a Yankee Redneck"! (Though I grew up in Hawaii :rolleyes: ).

I actually own a Rivnut "gun", but I'd given up on saving it after Hurricane Irma rusted it into one piece. :( It took a few days of WD-40 soaking, a little tapping, and using brute force on the handles, to restore it to normal working condition. :) (Stamped, "Made in England", FWIW).

There is a slight curvature to the plate that seems to match well to the keel? This is correct or should it be flat? Maybe the CARRIAGE bolt had been over tightened at some point?
The only Sunfish I've owned that would provide that answer was sold ($800) within days of my purchase ($150). :) I had only polished a tiny fraction of its faded maroon deck before I had a buyer! (Sold to my future ophthomologist :p).
 

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I think the round rubber thing is a cushion to go between a main sheet cleat of this type and the deck. Given the age of this boat, I think the cleat actually had an offset cam in it to snub the sheet, but I cannot find a pic of that style cleat.
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The circular black thing looks like an aftermarket drain plug, not an original Sunfish part. Yes, your bronze keel plate is bent and should be flat to work best. Fortunately cast bronze is ductile. Just clamp the thin part in a vise and gently tap the thich part back to straight with a small hammer. An easy fix.

Alan Glos
Cazenovia, NY
 
I think the round rubber thing is a cushion to go between a main sheet cleat of this type and the deck. Given the age of this boat, I think the cleat actually had an offset cam in it to snub the sheet, but I cannot find a pic of that style cleat.

Is this the cleat?

It has an offset cam, and on a very original Sunfish—the one mentioned above.

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ou say "spar" varnish, but is it "polyurethane" spar varnish?

You'll need fewer coats with polyurethane. Older varnishes (what I use) could account for the "several coats" you'd been previously advised.

Yes, it is modern polyurethane. May not meet specs, but it is what I'm already using on a dresser project for my boys.

The name sounded appropriate...:rolleyes:

Minwax® Helmsman® Spar Urethane

I'm up to 3 coats so far. I'll probably end at 4. I'm a sucker for pain.
 
Rub some dirt on those gelcoat divots, you won't notice them from a galloping horse.
Yeah. I know they are not visible (at 60 miles per hour - as I say) but at high magnification they sure look scary and like I burned the holes with clorox. I'd love to squeegee some sealant in there, but I suspect that is not appropriate - too much like painting.

Thanks for getting up early, Signal Charlie, to detail all that valuable feedback.
 
As to the whiteness of MarineTex patch, expect it to yellow over a few seasons if left unfinished. Check the contrast after every season, and see if a color match can be made over that small area.

I'd try a clear coating of Krylon clear spray paint to stop the yellowing progress. You can also paint the entire hull bottom with your choice of color. I'd stay with some standard, easy-to-find, white color--like "Appliance White". (Caution--that's still whiter than Sunfish white).

As to "polyurethane", I also use Minwax Helmsman Spar Urethane when a job calls for polyurethane. It puts on a thick coat for interior work, but I'm still hesitant to use it for marine use.
 
Here is the area where I took the photo of the gelcoat pores. The photo is bottom up. This condition is present on the gunwale more or less all around.

So I did not cause these pores either?
Gelcoat is brittle. :oops:

Could the "pores" be an accumulation of damaging gravel hurled from rotary lawn mowers or snow/leaf blowers? :(
 
MarineTex will yellow. We usually paint over it with Rust-Oleum White Semi Gloss, to bump down the gloss. Either spot paint or sometimes we do the entire bottom, 6 cans is usually enough. Touch up as needed, a tip given to us by our Guru Alan many years ago.

Another fun thing to do is get some Sunfish stickers made and cover the patch with fishes, wither tone on tone or contrasting color. When our friend Howie did mast step repairs for AMF he would finish up by painting a large gelcoat Sunfish over the repair area.
 
Drying the boat continues!
I know you guys are seeing me as obsessive. Maybe you can relate. Here is my obsession on drying the boat. Warm winter days are around 50°F. With the black plastic tent I can exhaust air over 70°F with my little 12v RV bathroom fan. It is pulling air into the cockpit through the shopvac pipe then from there into another shopvac hose through the mid-ship inspection port to the innards of the bow. The warmed air has to go all the way back to the stern inspection port and out. I checked later in the day and I had a 60°/90° differential. I’m trying to hold off weighing it again until we can be sure of a noticeable difference. It’s been only one month of varying efforts.

Boat Dryer.jpg
 
Could the "pores" be an accumulation of damaging gravel hurled from rotary lawn mowers or snow/leaf blowers?

Mr. L&VW,

With all due respect, good sir, this porosity is widespread and very regular in form. I'd have to agree with Signal Charlie that it could be a manufacturing defect. Otherwise my widespread use of clorox ate into the stuff based on the localized chemistry or physical properties. Or some other explanation related to a wide spread damage - mildew, freeze/thaw, oxidation, radiation damage.

That being said...

Either spot paint or sometimes we do the entire bottom, 6 cans is usually enough.

Really? Just spray paint the bottom? With common Home Depot Rustoleum??!!

Maybe. We'll see. I've been trying to avoid that. If the pores act like a sieve, I'll do it...later...
 
Q: "Really? Just spray paint the bottom? With common Home Depot Rustoleum??!!" - - -
A: This is the way...and I should have specified Lowes Rust-Oleum. Rust-Oleum has been around for boats longer than everything but Valspar.

"Maybe. We'll see. I've been trying to avoid that. If the pores act like a sieve, I'll do it...later..." I think you'd be well served to fill those pinholes with fairing compound, gelcoat, marinetex, paint, dilithium crystals, whatever compound you decide that you like. Gelcoat dribbled in makes the most sense.
 
If you have some PVC adapters, I'd extend a 3-inch pipe into the rear inspection port (at an angle) and adapt your RV fan to it. Inside air needs to circulate, and have an adequate space to exhaust. Might as well install the forward port...Don't most of us install a 6-inch port, forward?

In hind sight, I have L&VW to thank for the influence on my boat dryer. I think his post has been working on me subliminally.
 
L&VW = Jedi Mind Tricks, be careful...

Pinholes can be caused by moisture in the sprayer lines, among other things. About the time your boat was made the factory was cranking out about 60 boats a day. Day crew popped boats out of molds, glued them up and cleaned the molds. Night crew gelcoated and laid up the glass. It took one day to make a Sunfish. While wearing ties. Can you imagine?

Alex and Cort.jpg
 
Breeze Bender, What's your take on my gelcoat porosity question?
My take is the same as it was earlier- wash, wet sand, rubbing compound and wax. I enlarged your photo and saw only one tiny spot that I might fill with thickened epoxy or Marine Tex. If you want to paint it take Signal Charlie’s advice- spray Rustoleum gloss white on the bottom and sides.
 
Prefer deck to be not shiny to reduce glare on the eyes, one of the reasons we use the BlueGlo White TotalBoat or Interlux vs straight white.
 

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