Boat seats

[terzaghi]

I purchased three seats for my boat over a year ago. the seats all have the standard swivel base on them and the swivel is removable. I want to mount a seat on the front. Below the front there is a waterproof compartment that I would like to keep water proof. The only way I can see to get this seat mounted is to use self tapping screws. I don't think this method would hold up to years of wear and tear. Anyone have any advice?

[irishfield]

HIGH Quality blind rivets!

[pikehunter]

I have the type that are on a set of aluminum slides so the seat can be slid from left to right. They are screwed to the aluminum seat and haven't had a problem yet. Been there since the boat was new in 2005, not that many years true, but they hold my weight so that says something!

 

Link

website picture of sure mount seat bracket

 

You can buy these brackets at most marine dealers, some tackle shops and I think BPS has them too.

[Greencoachdog]

What type of material are you fastening to? Is that aluminum or ply wood? Either way, self tappers won't hold up. The integrity of your waterproof compartment will depend on installation procedures, use lotsa high grade marine grade silicone caulk in any drilled holes and on your fasteners too!

 

If thats aluminum, I'd recommend stainless steel machine screws with loc-nuts and a reinforcing plate or plates on the underside. If it's plywood I'd use Stainless star nuts... and then there's always good ol' Construction Adhesive!

[NANUK]

Looks like an enclosed floatation foam chamber to me,

for a durable solution, here is what I will do, cut a 3/4" pressure treated or marine grade plywood to the exact shape to fit the top of that platform, then cut a 6"x6" hole in the side of that aluminum chamber, in the middle and about 1" below the top edge, you'll be looking at some foam now, cut and remove about 3" of the top of this foam all directly under the aluminum to gain access to the underside, glue the plywood on top using marine grade sealer and then screw it down with SS machine screws, flat washers and lock nuts(you can cover the plywood with marine carpet if you like).

now put your choice of seat base(aluminum) and screw that down right through the plywood and the aluminum together, again use SS machine screws, flat washers and lock nuts and a marine grade sealer , once everything is screwed down get a can of spay-in.foam or Handy Foam(Home Depot) and fill up all the gaps where you had cut out the old foam, starting from the back area(the bow) don't over do it because the stuff expands a lot, and use rubber gloves, give the stuff at least 24 hours to expand and dry. then just clean up whatever foam is sticking out of the 6x6 hole.

cut a 8"x8 piece of aluminum sheet, put a bead of marine sealer on all 4 sides, place it over your 6x6 access hole so that it is square and evenly overlapping by 1" on all 4 sides and screw or rivet it together.

its a bit of work and will cost more then just screwing the seat on top of the aluminum but it will be solid and the top aluminum will not flex and crack under the weight of a person after a few years.