Re-Fastening shoebox deck/hull joint

I'm about to refasten my deck/hull and I have rivets and washers. I have the largest rivets I can get without a special riveting tool. The boat has been taken apart before and the lip of the deck and hull are full of holes. I'd like to use the same holes that I drilled the rivets out of, but I'm afraid that the rivets won't catch. I have washers for the rivets, but I don't really want to spend a couple of hours up under the deck (small boat) holding washers on while someone else rivets. I've contemplated having a piece of thin sheet metal bent into a "v" and slipping it over the lip on the hull before reassembling. There should be enough room to fit something the thickness of residential flashing. Probably even thicker. My worries are that this will keep the sealant from glueing the two halves of the boat together. Even if I goup the inside and outside, metal isn't as good a surface for adhesion as the rough fibreglass. <br /><br />I also don't really want to do fibreglass work all along the edge of the hull.<br /><br />Anyone have any thoughts, comments, or experience on this?<br /><br />Thank You.

Re: Re-Fastening shoebox deck/hull joint

Are you using poprivets? If so, if there is any slop in the hole you should really go to the next size up.. Sorry... Could you glue the halves together with either thickend epoxy or 5200? I can not make out from the pics if you are having to through rivet or are going into a tab. If you goop the joint up with adheasive and then rivet, the joint strength will be in the goop and the rivets will serve to hold the halves inplace until the stuff sets up. Just pray that you will not be the poor SOB that takes it apart next time...

Re: Re-Fastening shoebox deck/hull joint

I was the poor SOB that took it apart last time. Lucky for me it was put together with what I think was residential exterior silicone sealant. It was brown. Don't know if that's an indication of any popular marine make. I shoved an old kitchen knive into the shoebox joint after drilling out all of the rivets and hammered the dull side of the knife until I got all the way around. Good way to find rivets you missed.<br /><br />I don't plan on putting it back together with epoxy, but I do plan on using the 3m above waterline marine sealant. That's another reason I'm a little concerned about riveting. I'm not sure how long I'll have to work before everything sets up. My biggest worry is the bondo bed for the motor mount. It will only give me about 10 mins to get the deck on and in the right place. I think it means that I will have to carry the deck with sealant gooped all on the inside of the shoebox lip, drop it in place, pin a few rivet holes to make sure it's in the right spot and the transom is bedded right. Then it's set. I have to rivet it where it is.

Re: Re-Fastening shoebox deck/hull joint

just a couple of extra thoughts<br /><br />-I want the rivets to pull the two lips of the shoebox joint together. I'm hoping that I have enough working time with the sealant that I don't end up just putting pressure on cured sealant. I think the sealant has a "dries to a skin" time which is in the order of an hour or so, but has much longer full cure time.<br /><br />the bondo bed for the motor mount is my big worry.

Re: Re-Fastening shoebox deck/hull joint

One thing to remember also is that the aluminum rubrail carrier also provides strength to the joint. Considering that a lot of boats had the joint stapled together with no glue at all tells you that anything more than that is sufficient. Personally, if I where doing your boat, I would set the cap on, apply 3M 5200 in sections between the cap and hull, rivet every six inches, and then screw the rubrail in every six inches with stainless screws. By the time you are done the whole joint is stronger than the rest of the boat. I didn't bother with any bonding compound between the splashwell and transom on my boat. The motor clamps it together, there is no strength advantage to it so why bother. Of course, now the splashwell is the only original part of my cap left now, the rest is in the local landfill....

Re: Re-Fastening shoebox deck/hull joint

Mark,<br />Jason has it right.. Check out the 3M site, 5200 or 4200 will work fine. You could set the deck in place all lined up on say 1" spacers, shoot the 5200 in (get a powered caulking gun) take the spacers out and let the deck down and mush the stuff out. 5200 is the invention of the devil for those who have to remove it, and strong as moonshine and gets in more places than marshmallow fluff...<br /><br />I am not sure what you mean by a bondo bed for the motor but having to work that fast with a piece that big does not sound like a good time.. For a filler piece how would a form made up of small foam blocks/wedges cut to fit around where you want the piece to be solid for the motor work? The edges can be held with high quality duct tape to stop leakage and the top can be placed in a dignified fasion. Then shoot your favorite thickened goop in through a small hole drilled in the top of the deck in to the void made by the foam blocks....<br /><br />I have never had any luck with rivets pulling stuff together, but have had really good luck clamping stuff then rivetting to hold it together. <br /><br />Better you than me on this one !

Re: Re-Fastening shoebox deck/hull joint

The bondo bed for the motor mount is because the top of the transom and the underside of the deck at the splashwell aren't perfect surfaces. The bondo fills any voids and eliminates the chance of any weight cracking the deck. Or at least that's what I thought it was for.<br /><br />There may be a way to fill it after. I like the idea of working in sections.<br /><br />I have no idea how I would clamp the shoebox joint for riveting.

Re: Re-Fastening shoebox deck/hull joint

oh. by the way. my rubrail is held on with the rivets as well. the rivets pass through the the rubrail and both lips of the deck/hull joint.

Re: Re-Fastening shoebox deck/hull joint

NOW I see the light... How much gap is in the joint?<br /><br />Remember, a bunch of little rivets can support a pile of stress TOGETHER. Sum of the parts idea. I used to fly a helicopter that weighed 10,500 pounds and all that held the transmission case together were about 20, 1/4 inch bolts and Proseal. In flight the weight of the ship was supported by the upper mast bearing which was in the top of the transmission case. I didn't really want to know that....