Strange old thru-hulls

[tyrol]

So Sean and Gord, when you say seal the edges of the hole, is that with the 5200, or do you paint it with a little epoxy?

[DeepFrz]

Tyrol, use epoxy to seal the laminate. Also, have you checked with your supplier about exchanging the ball valves with the proper seacocks?

Deep

[tyrol]

Okay, will seal with epoxy, thanks.

I can't return the ball valves. I could always sell them, but unless there's a safety or reg's reason, I'd rather not... I'm still not sure why they aren't acceptable?

[Joli]

Tyrol, they are not ok because the valve can break off between the flange face and the valve.

Sell em or give em away or use them for applications above the waterline.

[tyrol]

Okay Joli, will do. Thanks again for the help.
Anybody need any 1 1/4" Marelon ball valves?! ha...

[hellosailor]

AFAIK, if the flange we are all talking about is the dame flange shown in the big "orange" illustration as being a flanged nut? The flange is there to ensure that the nut has more surface area where it is fitting/pressing against the hull.

That flange would appear to be or do nothing more than what a separate barrel washer (large wide washer) is, just a means of spreading the load against more surface area. In which case, a flangeless nut should be no problem as long as a barrel washer was used with it, or a flanged nut used instead.

No? The flange does anything else?

[tyrol]

My understanding is that we're talking about the flange (or lack of one) on the seacock itself, not the flanged nut on the thru-hull . In other words the load from the seacock also must be spread over the surface area, not just transferred to the thru-hull, even if the thru-hull has a flange.

[Cyndimarcus]

Hi, we are looking at a Buchan 37
Are you happy with your purchase? How is it comming along? Marcus and cyndi
cyndimarcus@yahoo.com

[Roy M]

Having replaced a couple throughhulls in thirty years of practice, I agree with much of what has been said. I add only the following:

It doesn't matter a fig how big the hole you make in the hull when you remove the thruhull. Whack it out, however you can. Then, by installing a butt block on the inside, using care to make sure you have adequate support around the perimeter of the hole, and that all surfaces are well sanded and cleaned, and epoxied, you will have the base needed for the next step.

From the outside you will see your original hole, covered on the inside by a butt block. Feather the edge of the original hole with a grinder, then epoxy and glass the hole flush with the hull exterior. Now your hole is permanently and securely sealed, much like you'd do if you punched a hole going on the rocks.

Now, look at where you would IDEALLY rather have the original thruhull. Locate it for ease of maintenance, a better hose run, or cosmetic appeal. Place another butt block in that location, drill a hole, seal the interior edges with epoxy, grind the outside (or drill and epoxy putty) if you want a flush thruhull (you can make a flush fitting this way with a mushroom head thruhull fitting). Install the thruhull and voila! This isn't rocket science. Just make sure you can get a good base for the butt block and that you seal the thruhull well.

[tyrol]

Hi Marcus and Cyndi,
That's a tough question... I bought mine very cheaply ($9k) so you can imagine the condition it was in. I was looking for a project though, one where I could learn intimately about sailboats as this was my first boat and first experience even working on boats. Needless to say, after 8 months in the boatyard, about $20k in materials and hardware and countless hours (I did all the work myself) I was at the point where I was pretty sick of it. I got a LOT done (completely rewired, rebuilt galley, rebedded all the hardware, redid all thru-hulls, and on and on..) but certainly not everything I wanted to (I'd like to install a windlass, reno the head, replace cushions, install headliner...). And I had a LOT of free time.
It's now in the water (Point Roberts, WA) and I've had her up to 8.1 knots which I think is pretty darn good for the old sails that I haven't updated yet. She seems to handle seas quite well, you hardly notice the wake from big power boats, she doesn't heel excessively... Basically I think she sails better than a lot of modern boats but that is at the expense of some comfort (her beam is only 9.5 feet) and the expense of some convenience (no roller furling).
And when looking at your head (the one in the boat), you'll definitely envy the modern molded-fibreglass ones.
Bottom line is that I could have probably bought something more modern (or in better condition) for $30k that I think I might have been more happy with, I'm just not sure... I sure wouldn't know as much as I do now about my boat though!
Feel free to ask if you have more specific questions...
Cheers,
Ty