Through hull or new hull? Contessa 26

[stormalong]

Originally Posted by skipmac

Glassing in the hole, if done properly is a bit of a job. You shouldn't just fill the hole but instead grind back the hull to allow a 12:1 bevel for the layers of cloth you lay in. So if the hull is 1/2" thick at that point you need to grind a 6" radius circle around the hole, 1" thick would be a 12" radius grind.

I would just put in a new bronze thru-hull without a seacock and screw the proper cap on the inside.

A 12 to 1 ratio is only needed for a structural repair. Filling a 1-1/2 inch hole is not a structural repair. This is how I have filled such holes, many years ago with no sign of failure.

1) Clean off an area inside the hull a couple of inches beyond the hole with a grinder.

2) Taper the hole, wider on the outside than the inside at about 45 degrees making sure that the hole is clean glass and free of all caulk.

3) Apply a patch on the inside of the hull consisting of one layer of mat and one layer of cloth. Let it cure completely.

4) Sand the outside to again expose clean fiberglass.

5) Lay up alternating layers of mat and cloth discs until you have overfilled the hole. You can do about four sets of mat-cloth at a time without it getting too hot.

6) Grind the patch pair to the hull.

7) Optionally seal the patch with a barrier coat. I use the barrier coat as a primer to see how fair the patch is. If you can't tell there is a patch under the barrier coat you have done a good job cosmetically.


I filled in some unneeded holes this way over 20 years ago. I still have the same boat and other than seeing the patches on the inside of the hull you would never know they were there.

[skipmac]

Originally Posted by Pegu Club

We re-glassed five thru hull holes, a couple as big as 12” radius it was more time consuming than difficult to do, for me less holes in the hull the better,

Fair winds,

After taking on my first fiberglass DIY a few years ago I agree it's not really difficult. Just time consuming and messy, very messy. More so for the job I did that had to be done inside the main cabin because the finished bit (new fridge box) wouldn't fit through the companionway when done.

One problem with glassing in through hulls is the cosmetics and how much you do or do not care about the perfect repair. If any of the new glass is visible above the waterline you will have to do a LOT of sanding, filling and fairing to make it nice and smooth and then paint the hull or try to match the original gel coat. Below the waterline, meh. Bottom paint covers a lot of sins.

I do agree fewer holes are better. I have 11 below the water line and 13 about 4" above and would love to get rid of several of these.

[Cadence]

I would reinstall a through hull. Easier and a patch is always suspect unless a lot of work has gone into it, inside and outside. You may find a use for it in the future.

[MJH]

Originally Posted by Glass lizard

Hey guys! Thanks for all the advice so far on the refitting of my newly aquired contessa 26. Ive been giving some thought to this dilema for some time but cant settle on it. Ive removed the pump out toilet, y valve and all the waste lines. The lines and holding tank were total FUBAR and i have put in a composting toilet. Now theres a 1.5" hole in the bow below the waterline that doesnt need to be there anymore. Im not sure if i should re instal a through hull and cap it or just glass it shut.

Removing the 1 1/2" hole is a bigger job than most think if done correctly...are you confident you can do that level of hull maintenance? Get a professional fiberglass guy to do it or replace the thruhull and cap it off.

~ ~ _/) ~ ~ MJH

[billgewater]

So to summarize: -
A)
Glassing up the hole taking really great care to do the correct taper, ensure the resin adheres, cut and lay in the correct amount of skin irritating glass, let it all cure, sand back on both inner and outer surfaces, prime both sides, apply topcoats to match the existing surfaces, paying for the shore time, and resin etc. Face/dust masks, a heap of power tools, clean up solvents etc.
Asking friends if it looks OK. Feeling possibly a little emotionally insecure about the repair quality and constantly checking it over the next few years.

B) The hole already exists. Clean the two surfaces. Buy the largest quality skin fitting, valve and cap that fits the existing hole (later you can reduce the plumbing sizes inside the boat if needed). Install it with proper sealants. No grinding, no resins or glass no extra painting. Later, you, or a new owner will always have the option of using the fitting for some unforeseen purpose. If you are dealing with a buyer, you can gently brag that you put the fitting in to provide the buyer with options. What a thoughtful guy! With the valve installed any new use can be done while the boat is in the water. No lift out required. Big savings all round. More money and time for beer.
Bloody obvious to me.

[thomm225]

The thruhull plug the PO installed on my boat around 16 years ago is doing fine.

it appears like it would take maybe 30 minutes to an hour to install the plug.

The exterior photo shows how closely it fits to the hull.....

[CMO Tashina]

Originally Posted by Glass lizard

Hey guys! Thanks for all the advice so far on the refitting of my newly aquired contessa 26. Ive been giving some thought to this dilema for some time but cant settle on it. Ive removed the pump out toilet, y valve and all the waste lines. The lines and holding tank were total FUBAR and i have put in a composting toilet. Now theres a 1.5" hole in the bow below the waterline that doesnt need to be there anymore. Im not sure if i should re instal a through hull and cap it or just glass it shut.

My predecessor owner used the existing through-hull and designed a pump out for the composting toilet's urine tank. Makes it a lot easier dealing with urine discharge when off shore.

[Jasoninbarrie]

I recently found a Contessa that I'm starting to work on as well, just a bit north of you in Meaford.

On mine I have to seackocks in the V berth. I have the small water inlet thru hull for the head, and an unused thru hull likely put in for a potential overboard discharge long ago.
I hope to glass in both as the seacocks are under the V berth will get little to no attention, and would prefer the space uncluttered. Personally considering the compost toilet (and associated space) as more a perk for resale on a small space boat.

What compost toilet did you go with?
I have not removed the old Jabsco yet, so not sure what space I have as a footprint.
If I need to keep the Jabsco, I would hope to move the seacock to beside/behind the head. Some holding tank repairs are leave me hoping for the simple compost toilet.

Hope this doesnt high jack the thread too much.
😁

[pcmm]

Originally Posted by skipmac

Glassing in the hole, if done properly is a bit of a job. You shouldn't just fill the hole but instead grind back the hull to allow a 12:1 bevel for the layers of cloth you lay in. So if the hull is 1/2" thick at that point you need to grind a 6" radius circle around the hole, 1" thick would be a 12" radius grind.

I would just put in a new bronze thru-hull without a seacock and screw the proper cap on the inside.

If you have access to the interior where the hole is, the better "repair" is to do the same type of patch on the inside as outside, which requires grinding a taper in the inside also. which in the end means the radius you have to grind on either side is based on half the thickness of the hull. If you don't have good access to the inside to grind then yes. Of course that is most of the time, lol!!

I did this to close in 15 old thruhulls on my boat! For a while we thought about changing its name to "swiss cheese"

[Glass lizard]

Yah my olding tank and all the fitting and lines were total junk. I ripped it all out and the pump out toilet and got a small composting toilet called a C-head. They produce a small composting toilet that fits neatly in the cubby in the v birth. The toilet works fine with very little odur (as long as you stear clear of taco bell). But you could make your own fairly easy and it would save a pile of cash. It is essentially a 500 dollar bucket to crap in. I use the space where the toilet used to be for storage.