Let's talk about reattaching caps

[theFunsmith]

As I get close to getting my deck stuck down, I am looking on to rebuilding and reattaching the cap. I am looking for advice on getting it stuck back on to the boat. I am thinking of loosely screwing it into place and then attempting to squirt epoxy in between the hull and cap before tightening the screws and nuts fully. Anybody who has been here before and would like to share any advice or a maybe better method would be very much appreciated.

[RickK]

Some people have glassed the cap on

[mshugg]

Rather than screw before squirting, you can squirt your adhesive, screw every few feet, then go back and add screws about every foot.

If you’re useing thickened epoxy to bond the hull/deck seam, you probably would want to glass the inside seam.  Thickened epoxy by itself can be a bit brittle for the stresses that the hull/deck seam gets.

You could also use methacrylate adhesive which is stronger and has less elongation than 5200, but is more flexible that the epoxy.  Downside of the methacrylate is it's expensive and requires a two-chamber caulking gun. 

Even 5200 and mechanical fasteners is superior to what the factory used.

[Levi]

 Anything beyond 5200 is overkill since the two parts were designed to have some flex.

[Fish Head]

Newbie here, why would you want to permanently affix the cap to the hull unless you are doing a enclosed transom? Maybe I am not understanding the post ala Roseanne Roseanne Dana.lol So here I go anyways. Thank God the previous owner of my 72 19’6 did not because that would have sure added to the fun of my rebuild. Between the screws that were used to hold the cap on and the screws to hold the rub rail on , Geez , I mean that cap was not going anywhere. Silicone was used in the gap between hull and the cap on the outboard sides and that was completely wrong I am told. Silicone is good for compression forces and not sheer forces. The silicone looked like somebody used a razor knife to cut it once I removed the rubrail. I plan on just screwing the cap back on and using 3m4200 to fill in the gap outboard to keep water from getting through. Also checkout the “Gorrilla” construction adhesive (waterproof) $8 a 9oz caulking tube at Lowe’s. I used it to affix the 1 inch thick PVC trim boards to the top of my stringers to raise the floor. Did a test with a 4 inch long piece attached to my stringer. Let it set for 3 weeks just to make sure it was dry. I needed a small sledge hammer to remove and it took part of the stringer with it. Figured that was good enough!

[mshugg]

Anything beyond 5200 is overkill since the two parts were designed to have some flex.

Overkill, maybe?  Remove the rubrail on a boat that has been run hard, and you’ll find spider cracks around the screws, enlarged screw holes and screws backing out.  That’s because you have a joint flexing around inflexible fasteners, and  fiberglass, while flexible in some directions, is relatively brittle.  The shoe box joint with sealant and screws is more an artifact of trying to economize on labor rather than because it is the best way to do it.  High end builders, building boats with high end prices, are useing adhesives like methacrylate, and glassing the seam. Is it strictly necessary? No, but most of us can’t resist little tweaks to improve on stock.

[theFunsmith]

I will be doing some research on those. Thank you guys for the info. Still all ears if anybody else has anything they'd like to add.

[mshugg]

Newbie here, why would you want to permanently affix the cap to the hull unless you are doing a enclosed transom?

Separating the hull and cap is not all that common even in complete rebuilds.  It's only really necessary if the joint itself is compromised.  If the joint is sound, its almost always easier and better to leave the joint intact. You can cut the sole to replace the tank, or even for complete stringer repairs.  Even in cases where the coring in the cap is rotten, there are almost ways to repair the core without separating the cap.

So, if doing a complete rebuild using all composites, there will never be a need to separate the cap and hull. The next rebuild on my boat will be to install the hydrogen fuel cell or the warp reactor, and it won't be my problem.

[Fish Head]

Hmmm..I think separating the cap from the hull in almost all rebuilds is very common. Especially when rebuilding the transom. Being my first rebuild and not wanting too bite off more than I can chew I was thrilled to learn I could just unscrew the cap about half way and support it with some 2X4’s to get it out of the way. Cutting the cap over transom and than having to reattach both end caps later seemed like a big PIA. I also decided to replace the transom from outside in because I did not want to cut into the liner and lose all that detail or have to recreate it. I understand every build has its own nuances and level of expertise of builder and of course budget. I am at the frugal end of all those but I do respect value! My father was a accountant what can say?
Who knows about the future, the future does not exist. Might be nice to remove the cap easily if some psycho runs into me with his jet ski and I have to make some repairs, just saying.
I think I might leave some room in the console for a flux capacitor 😁

[mshugg]

Fish head, If you check through the rebuilds on Classic Aquasport and other sites, you’ll see that most people just separate the aft 18 to 24 inches of the cap.  The cockpit sole too.  Tabbing the pieces back together is not a big deal.  It’s just basic fiberglass work, and It’s much less work than dealing with  the whole cap. 

Here’s one example: https://classicaquasport.com/smf/index.php?topic=8458.30

I actually removed the cap from my CCP, because the hull deck joint was in pretty bad shape.  I ended up tackling some other modifications too, but it addd a lot more work to my rebuild.

[Fish Head]

Seriously only took 20 min each side to remove screws with the help of my lovely wife!
Less glassing to do now.

[mshugg]

 

Seriously only took 20 min each side to remove screws with the help of my lovely wife!
Less glassing to do now.

We were talking about two different things.  Most Aquasports are 2 piece, and that’s not an option.  Funsmith’s rebuild is useing all Coosa board.  Shouldn’t be a reason to ever rebuild the transom again.