Countersinking a thru-hull fitting

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Surveyor
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Countersinking a thru-hull fitting

Post by Surveyor »

I wish to install a flush mount garboard drain plug and countersink it so that it is truly flush. How does one create the countersink depression?

My first thought is to use a dremel. Any suggestions will be greatly appreciated. Pic of the fitting I intend to install is attached. It is 2-3/4" dia.

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Rachel
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Re: Countersinking a thru-hull fitting

Post by Rachel »

Not to take anything away from any of our suggestions, but when I was thinking about putting in a garboard drain (and we have discussed that here so there may be some threads in the archives), I found a page with a pretty good photo-report on flush-mounting a garboard plug. Scroll about halfway down the page:

Link to article showing flush installation of garboard drain

I can't tell if that's the Buck Algonquin one you have or not (looks like it might be), but the BA is the only one I've found that has both a bronze body and a bronze plug. Many have brass plugs even if the body is bronze. I did once get a BA one with a small casting flaw (hole) where the "key" meets the spigot, so you might want to check that area over.

One change I would make to the way the fellow did it in the linked article is I would not use stainless fasteners there but would use bronze ones.
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earlylight
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Re: Countersinking a thru-hull fitting

Post by earlylight »

Jim,
I installed a flush mounted garboard drain plug like the one in your photo in the keel sump of Early Light. The procedure I used is documented with photos on my web site at: http://earlylight160.110mb.com/InstallG ... Drain.html I hope this is helpful.
Dick Coerse
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http://earlylight160.net76.net
mitiempo
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Re: Countersinking a thru-hull fitting

Post by mitiempo »

If you have Dremel with the router attachment it could be used. I would go slowly, increasing the depth a bit at a time. A Dremel is small and easy to control freehand. I think it would be easier than using a grinder as in Rachel's link.

Also, not only did he use stainless fasteners, they were screws. Even though there is not any strain on a garboard plug I would fee better using bolts I think - in bronze.
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Rachel
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Re: Countersinking a thru-hull fitting

Post by Rachel »

mitiempo,

Good point - I didn't re-read the entire linked page, but rather just glanced at it to make sure it was the one I was thinking of, and happened to see the stainless fasteners mentioned.

I think I would use either tapped machine screws, or... maybe screws/nuts if I could get at the back/inside? I say "maybe" because between the sealant (think I'd use 5200) and tapped fasteners I might choose that rather than have the snaggy/non-smooth nuts and etc. inside the bilge.

Since the writer of that page said "pre-drilled" screw holes I would assume they were not tapped.

Now to go read Early Light's page...

...Ooh, that is the King of garboard drain installation pages - nice! I see you also felt that tapped fasteners would be a good idea (and, good enough vs. through bolting). Thanks - that is a great web tutorial and I'm really glad to have that linked here (so I can read it again when the time comes).

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Re: Countersinking a thru-hull fitting

Post by Surveyor »

Thanks everyone for the outstanding replies!

I am a little sad to only now realize that my fitting is a Perko and the plug is in fact brass :( Why on earth would they even consider selling something like this knowing full well that there is a high probability of it being exposed to a salt water environment. What is worse is I read the product description and it didnt register :) At $83 I hope Jamestown will be understanding and accept my return!

I will try to use the best ideas from all of the information that you guys and gals provided and do a first class installation.

CapnK, if you happen to read this, would you mind changing the title to "Flush mounting a garboard drain plug"? The fantastic info here might be lost otherwise. Thanks!
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