Installing 12 volt socket in cockpit

[amoret]

Hi, I'm about to install 12v outlet socket in cockpit of my boat. I'm wondering what should I use to seal the inside edge of the hole. I'm thinking epoxy resin or oil based wood primer. The cockpit is plywood construction.
Many thanks in advance.
P.S. I'm a novice at this and don't want to stuff it up. Any advice gratefully received

[bletso]

To do it correct it will take two days. First coat the hole with a penetrating epoxy to seal the edge of the ply. When cured use a standard marine caulk such as 3M4200 of 3M400UV. For one hole I would suggest you find someone with the material to let you use some. The caulk, once opened will cure in the tube. (I have had good success storing it capped and in the fridge.)

[hobopacket]

Yup. Also, make sure you dab a little 4200 on the screw holes that actually attach the socket.

Also, do yourself a favor and use good quality connections for the wiring. I always use the kind that have heat shrink built in and then I use heat shrink tubing on top of that. Corrosion finds its way in easily.

[amoret]

Thanks for the advice, very helpful and will be heeded.

[amoret]

BTW, I'm not sure what you mean by "penetrating" epoxy. I have some Wests epoxy resin, will that be penetrating? Maybe thin it with turps?
Thanks

[bletso]

Just thin some epoxy down with a little acetone. You are trying to saturate the end grain around your hole.

[Russ]

To Be Clear:

The epoxy coating is to SEAL the hole edges in the ply. Great, do it as they said BUT If you ever hope to get that socket out again in the future DON'T 3M 4200/5200 You'll never get it out! (without damaging the ply big time)

All you need to do is SEAL the hole/socket interface with silicon around the edges of the hole/12V socket)! The 3M will seal it too but it is a sealant/adhesive/glue. I use it to seal stuff all the time on my steel boat but it is stuff I never plan to remove/can't risk a leak, like a through hull transducer! The 3M stuff is great but "permanent"
Just FYI Russ

[Terra Nova]

Originally Posted by bletso

Just thin some epoxy down with a little acetone...

NEVER add anything to epoxy that is not specifically recommended by its formulator.

OP--Use an appropriate epoxy, such as WEST, for sealing raw edges of bored holes in wood, fiberglass, ...

[Sailshabby]

Originally Posted by Terra Nova

NEVER add anything to epoxy that is not specifically recommended by its formulator.

OP--Use an appropriate epoxy, such as WEST, for sealing raw edges of bored holes in wood, fiberglass, ...

I had to repair a cracked cockpit coaming once a called Gudgeon (West Epoxy folks) and they advised adding a bit -10% if memory serves, but it rarely does - to the mix to facilitate getting the goo in.

[daga]

Don't overlook the fitting itself! Buy the best quality 12V socket, sealed at the back and with a cap that seals, that you can find. The one I bought has a press-fit plastic cap that constantly flicks open. Consequently the inside is already corroded after only a few months.

[a64pilot]

If possible install the socket facing downwards and put a liberal coat of silicone grease on all the metal parts. If done that way they will last many years.

[EmeraldCoastSailor]

In addition to mounting facing downward, I agree that using an adhesive sealant might not be the best choice if you ever want to switch out the cig style unit with a 5V USB unit, or if the cig style unit gets mucked up and needs to be replaced. If there is mechanical fastening associated with the situation involved, and all the 12v sockets I have installed either use a tightening ring or screws on a faceplate, I always use butyl tape for solid leak protection and easy removal if needed. The epoxy or sealant you use to waterproof the edges of the plywood needs to be fully cured before installation of the socket IMHO.

[amoret]

Hi and thanks for all the info supplied.
Install is now complete and looking pretty good thanks to all the advice supplied.
I practiced using the hole saw on a piece of scrap ply then put tape over the surface before cutting in. Drilled a small pilot first then held my breath while I sawed a hole into the cockpit of my boat. To my relief it was a neat, clean cut.
Heat shrink over the terminals/wire connections is good idea.
Used Wests epoxy and when cured installed socket with Sika sealant.
All looks quite tidy and snug.
Thanks to all for your help