I just bought a fiberglass boat and had to tear out the blocks the seats were on because they were rotting. The problem is, I don't know how to build and install a new wooden box to put the seats on. How can you do this to a fiberglass hull?
Yeah, that's a pretty common fix. If you have any pics it will make it easier for us to SEE what you are dealing with. There's a link in my signature that tells you how to post em. Basically you will build em, coat em with resin and glass, grind the deck down to bare glass and tab the new boxes in, paint and your done. If you have carpet then you will have to take it up and reinstall.
Yeah. I'll upload some pics tomorrow. I have already torn out the carpet and sanded down to the bear fiberglass. I just wasn't sure what do to next. I purchased seats from Walmart and want to mount them directly onto the boxes. The boat is a 14' Crestliner Mustang. The motor is a 61 Johnson 40hp Electric Seahorse, but I have no idea when the boat was made.
Also, any advice on what paint to use to cover over the fiberglass on the inside? The previous owner carpeted the interior of the hull. I had to sand all the carpet glue off. I want it painted. What do you think?
What kind of Seats did you purchase? Back to Back Lounge seats? Individual Single Seats? I might have a better Idea for you other than boxes.
As for Paint, Rustoleum Professional Oil Based Paint is what I used on mine. It will last a LONG time in a boat.
Ha. My wife just told me she didn't buy the seats. We were looking at the back to back seats, but weren't sure how to get that big box they sit on in our little boat. We'd like them, but we're also open to the single seats. I am really open to anything. Building those boxes sounds like a pain.
By the way, I've been looking at original pictures online in the old catalogs. Many of the 14' Mustang Crestliners had a bench seat in the front. What do you think about that?
How would four seats like this work?
This is what we're considering. We'd like to avoid mounting them on pedestals but rather onto some kind of structure in the boat. Any ideas?
First off, I would build a Proper Deck for the boat, to give myself a foundation for the seats. I would then build pyramid pedestals to mount the Individual seats on. You would toggle bolt them to the deck.
Option #2 would be Bench Seats and you could mount those seats to the benches
When you say "tab it in with fiberglass" do you mean cover it with wet-out cloth fiberglass? You suggest building a deck. How do I adhere it to the hull. That's my major hang up. Is there some kind of glue? Should I foam in under the deck?
When you say toggle bolt, do you mean the pedestals or the seats to the pyramids? Also, is it simple to bolt the seats included in my post above to a bench? I'm trying to avoid purchasing the pivoting metal pedestals.
This ain't great but it will give you an idea of what I am talking about. You will you Polyester Resin and 1.5oz fiberglass mat to cover the deck and TAB it to the sides of the Hull. Yes I would recommend using the BLUE slap foam sheets you can buy at Lowes to put under the deck. I would also put a center stringer down the middle of the hull for Deck support. I have include a drawing for that as well. Hope this helps. You Don't have to use the 1708 biax to finish the deck. 3 Layers of the csm will be fine.
You would toggle bolt the pedestals to the deck. I would recommend the flat swivels for the seats to be mounted on.
So, I've been doing some searching. Does Lowes sell the materials you suggested? I found a basic PL adhesive but can't seem to chase down and of the fiberglass.
Has anyone had any luck modifying the height of these chairs? The plastic base looks like I might be able to cut it down a bit. They're a bit too high for my boat. If you think it is possible, please give me some advice on what you think might work.
If that's the same molded plastic base that my new pontoon seats came with, then yes. It is very easy to work with. I'd leave the bases of the seats intact and cut them down from the top. A double cut saw, or even a dremel will zip through that plastic with no problem. You may want to purchase a plastic welder from Harbor Freight and maintain the upper lip of the seat base to "weld" back into the box base for structural support, but it should be easy to modify those to your needs.
Has anyone had any luck modifying the height of these chairs? The plastic base looks like I might be able to cut it down a bit. They're a bit too high for my boat. If you think it is possible, please give me some advice on what you think might work.
I will move this post to the restoration section and you will find ton's of information 
