Sealing Deck Penetrations to Prevent Core Rot

[Bob S]

Maine,
I appreciate the time you take in helping us through all our boat maintenance chores. I am adding Garhauer adjustable fairleads to my boat. I removed the tracks, about (25) ¼” holes on both sides. I read and re-read your “Sealing Deck Penetrations to Prevent Core Rot”. After filling each hole with thickened epoxy I noticed 3 holes that receded. One hole cored out using a Dremel 115 bit took 6+ syringes of epoxy. One big channel or void. I used Gorilla tape and must have ran below 10 times praying it wasn’t drooling thickened epoxy. The Gorilla tape sealed perfectly. Not sure where all the epoxy went? Did this Sunday and noticed today that one hole is about a 1/8 inch below the deck. You mentioned “Don't let the epoxy cure entirely or you'll need to remove the amine blush and this can be a royal pain in a small hole.” When I fill the starboard side I plan on topping off this hole. I used Progressive No Blush epoxy. Any suggestions on removing the amine blush? Can I use a carbide burr to rough up the top surface?

Your workmanship is impeccable! I'm a little worried when I re-drill the holes that I stay inline/parallel to the original ones. I keep in visioning how easy it could be to drill dead center on top and off center below. Any tricks?
Thanks Bob S

 

[All U Get]

Your workmanship is impeccable! I'm a little worried when I re-drill the holes that I stay inline/parallel to the original ones. I keep in visioning how easy it could be to drill dead center on top and off center below. Any tricks?
Thanks Bob S

Hi Bob,
I was thinking the same but the washers are fairly big for my stanchions so being off center a little would be OK. Maybe going half way from top and bottom would work. I had made a depth guage for a different project on my drill and might use it for drilling. Here's a picture of the simple guage. It works when drilling masts and booms when you don't want to nick wires or lines inside.
All U Get

 

[Maine Sail]

After filling each hole with thickened epoxy I noticed 3 holes that receded. One hole cored out using a Dremel 115 bit took 6+ syringes of epoxy. One big channel or void. I used Gorilla tape and must have ran below 10 times praying it wasn’t drooling thickened epoxy. The Gorilla tape sealed perfectly. Not sure where all the epoxy went?

This happens frequently with hand laid boats. Infused decks don't have these issues nearly as bad as the vacuum created draws the resin into the "kerfs" in the balsa or foam. Catalina used a lot of plywood and this is highly susceptible to channeling..

Did this Sunday and noticed today that one hole is about a 1/8 inch below the deck. You mentioned “Don't let the epoxy cure entirely or you'll need to remove the amine blush and this can be a royal pain in a small hole.” When I fill the starboard side I plan on topping off this hole. I used Progressive No Blush epoxy. Any suggestions on removing the amine blush? Can I use a carbide burr to rough up the top surface?

The Progressive Epoxy Polymers no-blush is a no-blush resin therefore you do not need to remove any amine "blush". Just go over it as soon as you can to try and get a chemical bond as opposed to mechanical. Some epoxy has a longer open time window than others. Either way it should still bond well. A q-tip can work though in a pinch.

I'm a little worried when I re-drill the holes that I stay inline/parallel to the original ones. I keep in visioning how easy it could be to drill dead center on top and off center below. Any tricks?
Thanks Bob S

They make drill guides that will keep your drill in-line with the deck. They are kind of sloppy but can work. You can also use a short piece of wood or aluminum as a 90 degree guide if your drill bit is long enough.