What is the best way to protect against water intrusion when screwing things to deck?

joe_nj

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I'm installing a new wooden floor using marine plywood, epoxy resin, and 10 oz cloth. I've got to reattach pumps, battery, seats, and a few other things.

What options do I have to prevent water seeping into my deck around the screws?

I read one thing that says to make a larger hole, put filler in it, then drill through the filler. Is there an easier way?
 

Scott Danforth

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Re: What is the best way to protect against water intrusion when screwing things to d

or use 4200 on each and every screw.
 

jigngrub

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Re: What is the best way to protect against water intrusion when screwing things to d

Mount your accessory and then remove it, squirt 5200 in the screw holes and dip the screw threads in 5200 and reinstall.

You cand also glue a mounting block to the deck and then glass it over and mount to that, if anything rots it'll be the mounting block and not your deck.
 

joe_nj

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Re: What is the best way to protect against water intrusion when screwing things to d

Thanks!
 

Yacht Dr.

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Re: What is the best way to protect against water intrusion when screwing things to d

Yup.. I agree on the 5200 and not 4200 for screws.

YD.
 

srollin

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Re: What is the best way to protect against water intrusion when screwing things to d

I'm sorry to ask this; what is 5200?
 

Woodonglass

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Re: What is the best way to protect against water intrusion when screwing things to d

It's a marine sealant.
00000776.jpg
 

srollin

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Re: What is the best way to protect against water intrusion when screwing things to d

Sweet thanks!
 

jbcurt00

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Re: What is the best way to protect against water intrusion when screwing things to d

Often available at HD (here in WV anyway) in a tube just like painters caulking.
 

Mark42

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Re: What is the best way to protect against water intrusion when screwing things to d

There is no better advice than you have already. Over drill the holes, fill with epoxy or thick resin and re-drill to a smaller hole for the screw. There is no better or safer or more water intrusion preventative that that.

i think once you have a cordless drill in your hand, with a depth ring (or even masking tape) on the bit, you will cruise through drilling the holes. Then mix up the thick epoxy or resin, and stuff in the holes with putty knife.

BWT, a sure way to ensure that putty makes it to the bottom of the hole is to stick a "coffee stirrer" or "mixed drink stirrer" in each hole. That way when the filler is pressed in, the air comes out the skinny straw. Pull the straw and pack afterwards to be tight.

Dont be a reaneck and use a "big gulp" straw. Use the skinny stirrers.

Regards

Mark42
 

joe_nj

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Re: What is the best way to protect against water intrusion when screwing things to d

They had 3M 5200 at two national home stores. I bought the 4200 also at West Marine before reading the subsequent posts - 3M says it's half the strength of 5200 for screws that might have to be removed, e.g., the trim pump or bilge pump. Sounds like the consensus is to use 5200 in all cases.

I liked the idea of epoxying in a board on top of the sole and screwing into that. I'll try it with the battery and see how it works out.
 

Yacht Dr.

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Re: What is the best way to protect against water intrusion when screwing things to d

What options do I have to prevent water seeping into my deck around the screws?

I read one thing that says to make a larger hole, put filler in it, then drill through the filler. Is there an easier way?

We ponder the question and answer. Predrill all the holes and dry fit..then squirt some 5200 into the holes and screw it down.

I liked the idea of epoxying in a board on top of the sole and screwing into that. I'll try it with the battery and see how it works out.

If the application can allow you to do such a top block.. I think its way overkill and is not an easier way of doing things..

Doing Just the epoxy in the oversized hole thing is not the best without 5200 involved. Again..you asked for an ez way that would hold up.

I personally dont like the oversized drill thing.. I would pilot just the same no matter if you used epoxy or not ( Use 1/8" drill for a #8 screw .. epoxy coat if you wish..re-pilot with 1/8", 5200 and screw down ( this is if you want that Extra added epoxy coating around the screw threads ))

So..what is it that you want to do..best on the cheap..or Best of the best of the best no matter what cost or time..

YD.
 
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