Fiberglass Sheathing a 1962 Carvel Hull

[Larks]

You can use an oxalic based acid to clean the SS and apparently the SS will then passivate itself over about two weeks - it works but is slower than using Nitric acid or citric acid. Clean the SS with the oxalic acid and a green scourer (ie not a steel or metal one), rinse it off and dry it with paper towels and put it aside for a couple of weeks and it will re-passivate itself.

(Stolen from here - I only learnt this myself a few weeks ago : https://spaco.org/Passivate.htm)

[gypsie]

Thanks larks - i have used oxalic (wood treatment) to clean SS. It's also really good at getting rust runs off paintwork - like when your old mild steel stem head fitting weeps down the stem.

[Larks]

Agreed, it’s very useful stuff - when I was with Paspaley Pearls we’d regularly go around the entire ship in the dinghy with a back pack pump of Oxalic acid to clean any rust runs from the hull sides (from working with old pearl farm mooring chains and anchors on deck rather than anything rusting on the hull).

[Slacko]

I boil SS parts in Citric acid for 30minutes if it is small enough.
It cleans the SS pans at the same time.

[gypsie]

You can buy Citric Acid is the supermarket.
I should get a half a kilo just to have.

What's the ratio? Table spoon per cup of water? Stir it in until it can't take any more?

[Slacko]

I make it probably 5 tables spoons per cup, or just a solid pour into the pot.

[gypsie]

Sorry for the lack of pictures. My phone has completely failed on that front. The dust has frozen it so it doesn't focus anymore.
As i get to know the camera in my phone i must admit i really admire it - so much packed into such a tiny little cube.

Anyhoo; Things accomplished this weekend.
First topcoat on the topside. I'm using Norglass enamel.
Cabin top primed with epoxy primer - norglass, not the high build primer.
First of the seacocks in.
swapped out the failing fridge compressor for a new unit that turns on. But doesn't make anything cold - i think there may be too much gas in the system now.


Question about painting - whats the opinion on sanding between topcoats?

The layer is thin, so sanding may take off a bit, but it'll be a week between coats. I was thinking of a 240 sand, quick skim, to key in the next layer.

[Boatsbgood]

FWIW I really prefer sanding between coats, even with simple one part paints, the finish just gets better (even if not perfect, it gets better).
With multi part, its the difference between "meh", and "oooh". Old-school enamel, the second coat hangs on better and the finish is better, even if not "oooh' level. 240, 0r 320, (taking off the gloss, not sanding hard for flat)for the reason you suggest as well as appearance.

[Andrew Donald]

Trev I’m using Norglass Weatherfast with a dash of Penetrol. Takes the pull outa the brush once you get the ratio right. I don’t sand between but I get next coat on within a day or so while first coat is still green. I’m too lazy to sand more than I have too. Mind you I’m talking about interior of boat, when I paint ext may be a diff story once I kick up the dust inside my shed.

[Lugalong]

Tricks mentioned about final cleaning of ssteel with citric or oxalic acid and a Scotchbrite pad sound like a good option after flapper disc and polishing, that is if there is no way to get nitric acid.

[gypsie]

Yeah it is tricky to get Nitric acid. Possible but tricky.

Gave the topsides a quick sanding. just enough to dust off the gloss and applied the second coat. as you'd expect, a definite improvement.
I'm using foam rollers. I've found you roll on as normal but then feather out to the point where the roller is dry. Then going back over the area you just did with the roller tips the paint really well. At least it looks like it did, I'll see next week.

My fairing is not that hot. Not rubbish, but don't look too hard. I'm surprised that the surface is not perfect at the local, 10mmx10mm, scale. that much fairing and sanding with 240....
As my mate pointed out, its more like Trev working on his boat on Saturdays while paying a mortgage and getting two kids to school, finish - which is about right.

Picked up my new rigging - shinny! looks good, old style bottle screws which i do like. Haven't noticed how to mouse them but.
Forgot to keep the bloody forestay - I'm fitting a furler so the end of the forestay is bare. But i don't know how much to chop off! The guy at Infinity rigging has the measurements. Nice guys and affordable.

Also got all my stop cocks in and plumbed up. Happy bunny, that was straight forward.
Cabin top sanded, not top coated yet.

[RFNK]

That's why it's best to use a shadow coat when fairing the high-build primer. The shadow coat highlights the low spots that you can't see.

[gypsie]

Not so much low spots, though there is most definitely an unfairness across the whole surface - its more at a granular level.

Got word from stainless guy - push and pullpit this weekend.

Man - that's so close to the end! I can hardly believe it'll soon be over.

[gypsie]

In anticipation, i bought one of these; https://www.coffeemachinespecialist....-maker-cx-25p/

[RFNK]

Not so much low spots, though there is most definitely an unfairness across the whole surface - its more at a granular level.

Got word from stainless guy - push and pullpit this weekend.

Man - that's so close to the end! I can hardly believe it'll soon be over.

The shadow coat provides a uniform grey cover. As you sand, the high spots become clear, the low spots remain grey. Once you have no grey showing, if you use the board or sander properly, you're left with a perfectly smooth surface for finish coating. Auto painters use this technique too.

[Slacko]

I discovered that "dry" foam roller technique a few years ago, the lightest pressure possible pops all those bubbles.
As far as the fairing goes, just think how good it will look after a few years and you are ready to sand and paint the next coat.
"Perfection is the enemy of finished". Not sure whose quote that is, but probably from someone who was ready to go sailing.

[RFNK]

Yep, I also tend to think that worrying about a perfect finish, especially on a hull, is pretty crazy. But good to know how to get a really good finish when you want it, though.

I think 'roll and tip' has disappeared with the introduction of good foam rollers. The only time I roll and then tip now is when I'm painting around obstacles or in awkward places, and even then, it's mostly tipping off where I've brushed rather than rolled.

I've also found, with really good enamel, like Toplac, and two-packs that, as long as I've avoided runs, I don't even need to do the dry roll. The little bubbles that the foam roller leaves usually just disappear without me going back over it with the drier roller.

[Smilemon]

In anticipation, i bought one of these; https://www.coffeemachinespecialist....-maker-cx-25p/

That looks like a nifty invention. Do you have a grinder for it as well?

I hope you can get a new camera soon as well, it's been a joy to watch your progress.

[sdowney717]

So, Peter, how do you account for all the older boats that have been sheathed successfully? Divine intervention? A miracle - what? I am so over people claiming to be experts telling us that things that have clearly worked well for many decades, because they've been done properly, won't work!

Looking through this thread and thinking about my coated hull which is still fine since 2005, how I was destroying the boat, would sink, dont do that, your an idiot, etc... brought back memories of why I put a bunch of them on ignore. Maybe they are too old and not familiar with better technological products of today. I just moved beyond them all. I see it still is all the same names. One of their biggest false theories was how PL Premium mixed with 30% sawdust thereabouts would pop out of the seams, which never happened. Fact is you do not need to cut and glue in slivers of wood for seaming. I let the hull planking get bone dry, and caulked it with that PL mix however big whatever gap existed got filled, then the whole hull coated over either with Santred Permaflex, PL Premium or Loctite Black roof flashing. And I have no leaks. I did all that after removing all bottom planks in quarter hull sections, renewing the framing with Treated SYP, and reattaching with bronze square drive screws one size up. I was able to reuse all mahogany planking cause I did not care about perfect seams, but really only one or 2 planks had worn edges.

[willin woodworks]

Splining and glassing is by now a tried and true method if done carefully as Gypsie clearly has.

Smearing a boat with tubes goop is not.

[sdowney717]

You can see what I am saying, got an immediate response too...
Then they will say using polyurethane glues is not a tried and true method, only epoxy is acceptable, well all my hull woodwork repairs is with polyurethane glues. I found the epoxy glue repairs cracked and failed.

[sdowney717]

Here is repair I did few days ago using a poly glue mixed with some mahogany dust, you can see how it swells, which for wood repairs is a blessing as it fill and locks the spline into the wood. I did the same between planks, but with no spline, just imagine this on every bottom seam of the lower hull.

Of course the planks are wedge shaped, closed at the frame between planks and open to the outside which was used for pounding caulking cotton and payed over with putty which hardens like a rock.
I just filled my seams with Loctite polyurethane PL glue and sawdust. Maybe it is just too easy... Mixing that glue with sawdust gives it plenty of moisture for curing and makes the dried material harder than the glue alone, it is sort of like as liquid soft wood which perfectly conforms to the available space.

Another nice advantage, this glue takes on the color of the wood dust you use mixed into it. Then it also easily takes stains or paint. And looks very much like the surround stained wood. Epoxy forms a dark glass like line when staining over wood repairs.

[sdowney717]

You want a nice sheathing goup, mix Loctite roof and Flashing Black polyurethane with 30% fiberglass milled fibers.
Take a 6 inch plastic putty knife and slather it on the hull, spread it like frosting a cake, The final layer you want about 1/8 to 3/16 inch thick. The Fiberglass milled fibers really strengthen the polyurethane rubber a lot (it is already very abrasion resistant without the added fibers) . It creates a waterproof tough membrane like a rubber tire on the wood.
It is very easy to spread onto the surface, not hard at all to do. And can easily added to with more on top. Plus paints, bottom paint too stick very well to rubber.
It will keep out the water, and the critters that eat wood. The coating is easily renewed in spots if needed when hauled out

You can also coat under metals to prevent corrosion as it is 100% water proof.

And mixed with the milled fibers, it can be sanded or even use a round steel brush in a drill to smooth any areas you want. When you do that, you will see the fiberglass embedded milled fibers glistening and sparkling in the sunlight.

The obvious advantage or rubber on wood, is wood is going to move and the rubber will move with it. So it can not crack and let in the sea.

[sdowney717]

Here it is


And here is is on the hull forward

[sdowney717]

Here it is going over some Sanitred Permaflex (a polyurethane coating I put on about 10 years before that) (no leaks, solid )
I stopped at this point as using the Loctite Roof polyurethane was an experiment, which turned out so far now after 7 years to be good.

I personally decided the Loctite mixed with milled fibers is easier to use and better than the permaflex (which has to be mixed and drips ), so that Is all I use now.
At this time, I did coat the entire keel in Loctite roof flashing polyurethane. The worm shoe was off here. I then put on a new worm shoe and overcoated with more Loctite roof flashing. I did not mix in the milled fibers into the keel coating. ( I ran out and thought ok, another experiment) (turned out fine). But I really recommend mixing in fiberglass milled fibers for the added strength etc, as I had been thinking might be good cause the bow could hit something... makes it go farther too as an extender.

[sdowney717]

I did the Loctite Black roof flashing coating 7 years ago now. Every summer I get in the water and clean off the hull with a scraper. Of course the bottom paint is well worn and it needs hauling, which I keep putting off. I dont see any real problems with the coating yet. except on the transom below the water where so many barnacle grow, and I scrape so hard, I ripped off some black coating. Barnacles are always going to be a continual problem.
the boat is slipped in a briny creek, not too salty. but the barnacles can still grow unfortunately in that marina.

[gypsie]

Thanks for sharing your technique sdowney. If it works it's hard to argue with it.
the patches you scraped thin, obviously you'll have to use the same material to fix up? How does new PU goop do on the old stuff? Good adhesion? Any UV damage. I've seen PU varnish last about 7 years outside, but it's a pain to touch up.

[gypsie]

Photos!

Got a new camera, but within days its got dust inside the lens. I'm going to throw this phone away once i get this project finished.

Raising the lowest point of the bilge;
The lowest point of the bilge is under the motor and more than one of my long arm's lengths away. So i want to build up that corner and have any water that does make its way into the boat, come forward to under the aftermost part of the cabin sole. I'll keep the bilge pump there and the whole issue of managing unwanted bilge water should be heaps easier.

Three boards in decreasing lengths that my 15yo cut and fitted roughly. (roughly - a chip off the old block).

IMG_8102.jpg

I've gooped them in place and poured some more somewhat thickened, but still runny, epoxy in around them. Not fully completed - i realise i'm low on epoxy and there are other jobs that need it - aka, the toe rail.

The board slook patchy and old - but they're perfectly good 15mm marine ply that has been liberally soaked in CPES.

[gypsie]

Collected my new rigging and installed all but the forestay. I forgot to keep the original forestay - so waiting for the rigger to send me the final dims. I have to assemble the furler before attaching it.

I like these bottle screws.
IMG_8103.jpg

[gypsie]

Installed all my through hulls as mentioned.
Here's some pics;

The cockpit drain;
IMG_8110.jpg

Through hull for the bilge pump - this is maybe 100mm from the sheer clamp.
IMG_8111.jpg

for those who don't know these valves, the wider peice by the hul skin is a load collar - so you don't put any pressure on the skin fitting when operating it. Neat solution. The cockpit drain is a 38mm fitting, and the bilge pump is 25mm.

All the fittings other than the cockpit drain are 25mm.
One exception is the gas locker - that doesn't have a valve, it is a 38mm fitting straight through the hull, about 400mm above the waterline.

[gypsie]

What say you the value of a scoop for the engine raw water intake? I have a strainer on it. Its a dedicated supply.
I've been trying to figure out how to attach one without piercing the fiberglass sheathing. I've been procrastinating on it - i feel i should have one, but i am very keen to maintain the integrity of the fiberglassing.

[gypsie]

Other than that - painting.

Aft deck primed - with some topcoat on the toe rail section;
IMG_8101.jpg

progressing with painting the cabin top and the inside face of the toe rail.
IMG_8100.jpg

The white paint on the deck is epoxy primer. i went round with a grinder and smoothed out areas of glass that overlapped when i did the deck - and printed through the deck paint. I'll use the same deck paint again.

I think this is with the third coat on the topsides;
IMG_8104.jpg

Up until now i;d been doing a coat a day on my saturdays - first off sanding to key in the new coat.
Last week i got two consecutive days so i was able to hot coat the final one.

here it is still wet, not bad, and as it tightened up as it cured it got even better.
IMG_8106.jpg

IMG_8107.jpg

Thats the fourth and final coat on the topsides.
next visit i mask off for the deck paint, paint a coat of the non-slip. mask off for the first bottom coat of white non-ablative (to be followed by three ablative).


Also need to give some thought to the boot stripe - any rules of thumb on dimensions? thinking 50mm above the waterline and 50mm wide. Maybe 20mm wide would be nice? I used to have 100mm but it was too bulky - though it did make the topside appear to have a lower profile.

[gypsie]

Then dry fitting some cap material for the cap rail.
the cap will be made of three pieces; 5mm x 25mm on the inboard face, 15mm x 35mm on the outboard face and a cap of 20mm high x 45mm wide.
Joinery is not my strong suit, but i'm hoping to do a half decent job on these. I want wood to be strongly present, now that i've wrapped the boat in plastic. The cap will also cover my somewhat rough toe-rail, and hide my functional, but simple scuppers - while allowing them to work perfectly well.

Did i mention that the planking of the topsides is printing through the sheathing

This is some of the inside face strip going in for a dry fit.

IMG_8108.jpg

I'll screw all the sections on, bedded in thickened epoxy. permanent, water proof.

IMG_8109.jpg

IMG_8112.jpg

[Larks]

Nice work Trev. I can’t say that I have ever seen a vessel, power or sail, with a scoop for the engine intake and I can’t really see a reason for one: it’d just induce drag and I don’t know what damage it could do by essentially pressurising the feed side of your water pump when under sail.

Just a thought on your through-hull fittings, particularly anything below the waterline, go for two hose clamps on each fitting and avoid those perforated ones that you’re using - they tend to break too easily and can pinch and tear a hose.

[RFNK]

What say you the value of a scoop for the engine raw water intake? I have a strainer on it. Its a dedicated supply.
I've been trying to figure out how to attach one without piercing the fiberglass sheathing. I've been procrastinating on it - i feel i should have one, but i am very keen to maintain the integrity of the fiberglassing.

I think any scoop is just going to pick up more crud. I think it's unnecessary. Are you concerned about piercing the hull for the water intake or would the scoop require another through hull??

The hull's looking really good!

I don't have a boot stripe. I actually don't like them. I just run the AF about 150 above the water and it looks great. I think your boat would also look great without any boot stripe. Your boat's looking really good!