seat mounts on new deck

[fireman57]

Just put a new deck in a 14.5 fiberglass boat. Had to use 1/2 in marine plywood as structure would not accept 3/4" as would have been above old floor. Put in new stringers and built a new mounting box for the front. All fiberglassed in. Resined both sides of plywood. shot screws in stringers and glassed it all. Looks good. Problem is with mounting the pedestal seats. I don't want them ripping out this deck.<br />Thinking of using a 2ft round piece of 1/8" steel with pedestal flange bolted to the underside of it. I would then shoot screws around the outside of steel plate and glass it in. Do you think that this would be sufficient to spread the weight across this 1/2" floor and prevent it from tearing out? I take two guys fishing regularly that weigh around 230lbs. I don't want to redeck this again. I would rather overbuild the seat mounts than keep replacing the deck.

 

[Sean Riddle]

Re: seat mounts on new deck

Sounds like that idea will be plenty strong. The weight distributioon should be quite good. The only drawback you might have there is that is an awful lot of holes to put in that brand new deck .If you put resin on both sides of the deck that will help to strengthen the ply considerably. I wouldn't think you would have to worry with the mounting screws pulling out. Have you thought of trying to fabricate a mounting plate with a larger base to help with weight distribution or you may be able to find a wider base already made to replace smaller bases you have. If you used epoxy you should be able to secure bases with resin , then when you put your mounting screws in you can coat the holes and screws with 3M 5200 for a good watertight seal. The fewer holes you have in that new deck the less chance you will ever have to replace the deck again , and that is a real good thing .................Hope this helps , RR

 

[fireman57]

Re: seat mounts on new deck

I have already resined both sides of the deck before screwind them down and then resined the top side again to seal any holes left by the installation screws. The widest base I have been able to find is 9 inches diameter. That would not be sufficient for weight distribution. I never thought about your suggestion of too many holes. I was going to mount the 9" flush seat mount to the plate with bolts and then secure the plate to the floor with about 8 screws. These screws will be around the 2 ft diameter so I don't think they will be close enough together to harm too much or weaken the deck considerably. I will then glass the whole shebang again to keep water out of these holes. Just wanted to get the opinion of somebody who has been there and done that. Thanks.

 

[fireman57]

Re: seat mounts on new deck

Sorry Riddler, I forgot to thank you for the suggestion of the epoxy. I'm going to coat the deck and the underside of the 2 ft steel plate with that and then but down my few screws and glass.