Holes for Self-Draining Cockpit

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blueflood
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Holes for Self-Draining Cockpit

Post by blueflood »

Hi all,

I plan on drilling six 1-3/8" holes for scuppers in the cockpit. Even thought all holes are oversized-putty-redrill anywhere where mechanical fasteners are used for cleats, handrails, grab bar stainless deck fittings, motor etc, I elected to not do that where only clear holes are present (motor well and those scuppers), not high stress areas. With the experts out there; Is min 4-6 coats of epoxy on the inside perimeter as an acceptable compromise ? (in my guts I know I should do but I am thinking engineering in this boat; not to spend resources on where it is not needed). Reasoning is that the hole bottom is so close to the deck, why bother with an epoxy "ring" evolution when the bottom portion of material would be no thicker than if applied as coats. The hole hugs the deck right at the bottom. Maybe I am thinking too much :lol:

Marc

Steven
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Re: Holes for Self-Draining Cockpit

Post by Steven »

I emailed System Three about the overdrill and fill vs. coating and they said just coating is sufficient. I still prefer to overdrill when practical. Another options is to use a strip of 3.25 oz cloth and line the hole. They sell it here and it just melts into the epoxy. It's cheap so I keep some on hand. I use an acid brush to smooth it into place. A 1" hole is about as small as is practical, but it works well. I keep it a little wide and then trim after it dries. One builder did something similar and inflated a balloon in the hole to hold the glass in place. I tired but could never keep the balloon from popping out. Since the drains are in the wet zone, I'd overdrill if possible, and glass if not.

blueflood
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Re: Holes for Self-Draining Cockpit

Post by blueflood »

Hi Steven,

Yeah great idea :idea: ! I am casting my own outside scupper flanges for detail so I will blend in the lightweight cloth and fair on that piece.

...maybe he used one of those long sausage balloons clowns make mutant animals from :lol: 8O

Marc

Steven
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Re: Holes for Self-Draining Cockpit

Post by Steven »

Tried those. I don't know how he made
it work.

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Re: Holes for Self-Draining Cockpit

Post by jacquesmm »

There is no need to email System Three: they know more than I about resin but I know more about boats.

The over size drill and plug with putty is mostly for bolts and things you anchor like a cleat.
A plain drain hole is not under any stress and can be coated with or without the addition of glass.
If you use glass, it helps to have something pressing the resin and glass to the hole.
I have done it with bicycle inner tubes, it works. I never tried latex balloons, it could work but the bicycle tubes stay in place and are easy to fill if you use the part with the valve.
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cali123
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Re: Holes for Self-Draining Cockpit

Post by cali123 »

It is a bit challenging to get the 12 inch party balloons to stay in the hole but with a little practice ,its fast and easy, I used 12 oz. biax rolled up and saturated with a ketchup like mix of epoxy and wood flour. I like how the large balloons conform to the outer part of the hole. You need an air compressor, air blower, and most importantly, balloon clips to seal the opening once the balloon is inflated. The clips can be purchased at a party store and are absolutely essential.

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Re: Holes for Self-Draining Cockpit

Post by jacquesmm »

cali123 wrote: . . .I used 12 oz. biax rolled up and saturated with a ketchup like mix of epoxy and wood flour. . . .
Agree that is an important part, wet glass saturated with a slurry of resin.
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