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Discussion Starter #1
My first big project on my little boat!

The Catalina 22 was built with a garden-hose style valve glassed directly to the hull for the sink and cockpit drain. I'm replacing it with a bronze thru-hull.

This might be mass overkill for a tiny boat that will be sailing on a tiny lake, but one of my goals with this boat is to learn how to do things The Right Way so I'll have the experience for future, larger boats.

So I've got a printout of Maine Sail's instructions, and a big pile of 1" bronze hardware:



Any tips, tricks, or advice?
 

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Discussion Starter #3
The G10 plate arrives tomorrow.

Since the three holes are sealed and glassed over is leaking really an issue?

I do like the idea of three fewer holes, but then again the screw-through-the-hull thing seems like it would be bulletproof strong.
 

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Daniel - Norsea 27
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I used G10 for the base too. I didn't use studs, nor did I use bolts through the hull.

I drilled through the bolt holes, then drilled a little larger area for the bolt heads so they would be recessed into the G10 plate.

Next time I haul out, I will have 6 or 7 more to replace and plan to install the same way. MaineSail's instructions were great help.
 

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Barquito
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Minnesail - Are you going to need to do some modifications to get rid the old fiberglass horn and make the hole the right size? Not sure what you mean by glassing over the studs. They should screw in from the outside of the hull. Can put some fairing over them for smoothness, but doesn't seal them. If you drill holes for the bolts that are the same size as the bolts, and use sealing material, it will be very water tight.
 

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Discussion Starter #7
I have Sikaflex 291 to use to seal the machine screws. I guess I didn't mean glass over the heads, I just meant to put some thickened epoxy over them. You're saying that's not necessary?

The existing fitting is on the keel slot, so it's on a sharply curved surfaced. I plan on putting the new thru-hull off to the side of that, on a flat part of the hull.



My plan is to cut off the "horn" and fill the hole with a thickened epoxy plug, then fiberglass over that plug on both sides.

I've never used epoxy or fiberglass before, so this weekend I'm going to play around a bit on some scrap wood to get the feeling for the stuff.
 

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No more curry buffets
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if you can get some chopped strand mat and make 3 or 4 little circles to fill the hole you're patching, that would be better. Wet them out thoroughly and stack them neatly in the hole. The foregoing sounds easier than it is.

I've not read Mainesail's article, but I have found that the shrink wrap plastic that is filling boatyard dumpsters everywhere this time of year makes a great backing material for filling a hole. It's got some body to it, and epoxy will not stick. Put a sheet against the hull, back that further with a piece of plywood, and jam it all in place with a stick and a wedge.

Edit to add: Holy heck that's a manly pile of bronze.
 

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Discussion Starter #9
if you can get some chopped strand mat and make 3 or 4 little circles to fill the hole you're patching, that would be better. Wet them out thoroughly and stack them neatly in the hole. The foregoing sounds easier than it is.

I've not read Mainesail's article, but I have found that the shrink wrap plastic that is filling boatyard dumpsters everywhere this time of year makes a great backing material for filling a hole. It's got some body to it, and epoxy will not stick. Put a sheet against the hull, back that further with a piece of plywood, and jam it all in place with a stick and a wedge.

Edit to add: Holy heck that's a manly pile of bronze.
Ain't it though? :)

My wife got no end of giggle out of saying "full flow ball valve seacock"

Anyway, you're saying chopped strand mat would be a better plug that sticking in thickened epoxy? How about woven fiberglass, would that work? I already have that.
 

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Discussion Starter #11
I have that printed out and that's what I'm going for, but the sharp curve of the keel slot confuses the matter slightly. The article says to make a plug and then seal it in with thickened epoxy, but I was thinking I'd just make the plug out of thickened epoxy that way I could mold it to the shape of the curve.

But again, I've never worked with epoxy before so it's highly likely that I don't know what I'm talking about.
 

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I don't believe the way to go is mixing epoxy super thick it needs to flow somewhat ?

But a picture of what your trying to change would allow better advise









http://i565.photobucket.com/albums/ss91/tommays/Seafever/2010_0515
_133044.jpg







On plugging just plain holes I have just beveled the carp out of the glass (12:1)and built up back to the surrounding thickness housing with various sized circles

I have also built various dams when i needed to fill and area or hold the stern tube in proper ailment until it could be reinforced with enough cloth for strength
 

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No more curry buffets
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I am just thinking that some chopped mat added to your thickened epoxy makes that part of the repair much stronger. Remember, epoxy hasn't much mechanical strength on its own. It's the glass that gives it all the strength. Woven mat would work too, it's just not as easy to work with or malleable in such a circumstance.

I imagine you are proceeding sort of like the "low stress hole" in the West Systems link, where you'll plug the hole, fair the outside, and back up the inside with a couple of layers of glass. My contribution just makes that plug a little better.
 

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I used G10 for the base too. I didn't use studs, nor did I use bolts through the hull.

I drilled through the bolt holes, then drilled a little larger area for the bolt heads so they would be recessed into the G10 plate.

Next time I haul out, I will have 6 or 7 more to replace and plan to install the same way. MaineSail's instructions were great help.
The removable studs are by design and there for a reason. Try to get a flange off that has been bedded and you will invariably damage the bolts/studs. You usually need to pry it at an angle and with studs in place that does not work, BTDT... If they can't be double nutted, removed and replaced you're pretty much going to need to cut the whole plate out.. Use tapped studs NOT captive bolts.... Each 5/16" stud, into just 1/2" fiberglass far exceeds ABYC strength standards and you have three!
 

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My first big project on my little boat!

The Catalina 22 was built with a garden-hose style valve glassed directly to the hull for the sink and cockpit drain. I'm replacing it with a bronze thru-hull.

This might be mass overkill for a tiny boat that will be sailing on a tiny lake, but one of my goals with this boat is to learn how to do things The Right Way so I'll have the experience for future, larger boats.

So I've got a printout of Maine Sail's instructions, and a big pile of 1" bronze hardware:



Any tips, tricks, or advice?
Decouple the tee from the valve with a length of hose that gets it above static waterline. If it is in a safe location that would be okay but best to come off the valve with hose, then to the tee...
 

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I agree with Mainesail. The higher the bronze fittings are the less force it requires to damage something.

If you use fiberglass mat beware that most mat is not compatible with epoxy. The binders that hold it together dissolve in the styrene in polyester. There is no styrene in epoxy. Only use mat if it is specifically stated "to be used with epoxy".
 

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Groco has backing blocks similar to Mainesail's no through bolt method. They don't state what material they are, I guess fiberglass.

From Groco's catalog:

 

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Discussion Starter #18
Decouple the tee from the valve with a length of hose that gets it above static waterline. If it is in a safe location that would be okay but best to come off the valve with hose, then to the tee...
That sounds like good advice, fewer hoses and fittings below the waterline.

It would take some heft away from my manly pile of bronze though :)

I suppose the thing to do would be to have both cockpit drains go right to a 90º pointed towards a T in the middle. That hose could be supported to the floor of the cockpit and they'd meet in a T and there'd only be one hose going down below the waterline. I may have to order more stuff.
 

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Learning the HARD way...
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That sounds like good advice, fewer hoses and fittings below the waterline.

It would take some heft away from my manly pile of bronze though :)

I suppose the thing to do would be to have both cockpit drains go right to a 90º pointed towards a T in the middle. That hose could be supported to the floor of the cockpit and they'd meet in a T and there'd only be one hose going down below the waterline. I may have to order more stuff.
If this is for cockpit drains, I suggest that you eliminate the "T" entirely, and bore another hole - meaning that you'll need another manly pile of bronze. By using a "T" you are effectively cutting the total draining capacity in half, and doubling the time that it would take to empty the cockpit, and doubling likelyhood of a plugged drain.
 

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A slight deviation of the thread please. Does anyone build an enclosure around seacocks? The top of the enclosure would be above the water line so if something should fail the water is contained in the enclosure ?

I now return you to the normally schedule subject of this thread.
 
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