Gorrilla Glue for leak-proofing

I would also point out that while Gorilla Glue does foam to fill gaps, this is ONLY a cosmetic fill, and has no structual strength. The foam has about the adhesive properties of dried whipped cream.

 

A lot of very valuable info here, thanks guys.

Just to give you a better idea of what I'm aiming for, it's basically going to be a box - shaped hull that will have the sides bent together at the bow. I'm planning to build it with 1/4" exterior grade plywood around a simple frame. The structural integrity is definitely not intended to come from the joints between the panels. I'm aiming to nail and/or screw the panels to the frame in such a way that it's as watertight as I can get it (with my limited woodworking experience ) - and then just adding in the adhesive to be damn sure there's not gonna be any water seeping into that thing.

From what I understand, a good paint job also helps somewhat with this.

 

Randomguy, are you working from an existing set of plans, or is this your own concept? That construction approach sounds a bit odd. Do post more info (plan reference, sketches, photos). You will surely get some additional feedback to help you out

 

alright, here's what I cooked up designwise

I realize this probably looks nothing like professional boat plans you might find in a book. I'm a CAD nerd by trade, so i figured I'd whip up a design on the computer that'd help me get the exact dimension right when i build this thing

 

Let me clarify a few things that these plans dont show. Firstly, the rods that secure the outrigger to the hull will be lashed to raised portions of the frame (this is a design that's intended to be dismantled and put on top of a car). The mast is also lashed at the base, and secured by ropes from the top to the bow, stern, and outrigger to hoops with a clip-on hook. The hull will be open on top, and the outrigger will be closed. Ideally, a person should be able to sit either inside the canoe, or on one of the boards resting on the rods that join the hull and outrigger.

That's the idea at least. Can't say how the actual thing will pan out, since I've got very little woodworking experience

 

The shame here is that for a few extra dollars and a little more research, working from a set of properly designed plans you could end up a nice little vessel. Actual build time would be less as you will not have to build in trial and error but follow a layed out set of instructions.I am not trying to discourage you here but the materials are very poor and your plans and approach just too vague. You will not be happy with the results. Be kind to yourself, locate a set of plans( I'm sure the members here can refer you to many, pratically free right off the internet) build your firtst craft from these using proper materials. It will be a good learning tool and a confidence building experience to aid you into your own design and build for the second project.

 

Not bad for an initial concept. At a glance it appears to be an outrigger sailing canoe. However, to get any sort of performance out of the hull it should have improved design & hydrodynamics on the hull & outrigger. You'll get nowhere fast with a flat bottom hull. Also, forget treated plywood & gorilla glue.

You need to think like a boat builder. I would suggest examining some existing plans.

e.g.

http://outriggersailingcanoes.blogspot.com/

And take a look at some good books on construction.

e.g.

http://www.amazon.com/Building-Outrigger-Sailing-Canoes-Construction/dp/0071487913

You're a CAD jock, so you should make decent enough cash to scout around & round up materials for a good price, and track down a good set of plans.

Such boats are not they're not that difficult to build. Building any boat out of wood is forgiving. Moreover, reviewing existing plans will help you hone your ideas. If you're lucky, there may be a set of plans out there that will suit you just right & save you a lot of trial & error.

If I were you I would go with a strip canoe. You can round up materials and build one very nice boat you'll be proud of...very strong, light, stable & fast. Best book on how to build a strip canoe is CanoeCraft, and for outrigger sailing canoes the reference above covers the outrigger & mast too. Between both books you'll have some great resources at your finger tips for building a nice boat for a good price. Properly cared for it may last you the rest of your life

 

RG, some good advice posted here. Make your first boat build with proper plans. You will get more satisfaction from a boat you can actually finish and that won't discourage you, one that sails as it should, one you get genuine compliments on and one that has resale value. When you understand how a sucessful design works your next design will be so much better.
Just my opinion. Keep us posted.

 

I may be the only one, but I like Gorilla Glue for building boats. I would recommend coating the outside of the hull with epoxy and a layer of glass. My approach is to use gorilla for the assembly and then seal with epoxy once it's together. Sure, epoxy is stronger than Gorilla, but for most applications Gorilla is strong enough and I find the mixing and measuring to be enough of a pain to prevent me from using epoxy on small jobs. Gorilla can also be used as a foaming sealer, though as someone mentioned it's not terribly strong when used this way. That said, if you have a gap you can't easially get to that needs to be filled, Gorilla will do the job.

 

Please correct me if I'm wrong, but when I used Gorilla Glue, I looked at what it was made out of (in the MSDS) and saw it was just superglue that foams up on contact with humidity. Is that correct?

Also, I did use it one one part of my boat build. I connected the dagger board foam together with it because there was just so many tiny NACA foil sections to bond to each other.

I know another builder who glued every piece of his entire boat core together with Gorilla Glue.

 

I'm not saying you're out to lunch here and it might be a case that I'm brainwashed or just plain stubborn but I just can't bring myself to using this general purpose product when i compare all the research and testing that has been done with epoxy specifically for the marine industry. Maybe for interior furniture and so on but I just can't convince myself it is suitable for majour use in high strenght applications such as laminated ribs-deck and cabin beams. I'd have to see alot of testing and results, compariable to what has been done with epoxy. Sorry but Gorella Glue doesn't have a big fan here as far as boat construction is concerned.

 

If you just want a waterproofing caulk, why not use a caulk? There are marine caulks, but if you want cheap and are using nails or screws then regular outdoor house caulk will work better than Gorilla Glue and is way cheaper and easier to use. If, on the other hand, you just want to avoid mixing epoxy, there are several types of epoxy in tubes which fit into a caulking gun. They’re expensive on a per-once basis, but you only need a little for adhesive and you'll save on the fasteners. Sure you can use Gorilla Glue, but it needs to be prevented from pushing the joint apart as it tries to expand or it will not develop much strength.

I question doing your own boat design to save money, that is taking a risk with the time and money spent on the boat, and risking your life in it. As a self-described CAD nerd do you have the design and engineering skills to create a boat design that will provide a return on your investment and preserve your life? If so, go for it, but look at real boat plans first and work out why boats are the way they are first.

BTW, there are several free boat hull design applications on the web including FreeShip and Carene2008. They don't do structures but they'll help get the shape right and analyze some stuff you really should know about before starting construction, like hydrostatics. They’ll be a piece of cake with your CAD skills.

 

When you say this builder "glued" every piece of his boats core material together with Gorilla Glue, do you mean it was bedded with strictly Gorilla Glue in a open lay-up process, say after the outer skin cured and before the inner skin was lay-ed up? I've used Gorilla Glue plenty of times in bead and cove construction and various interior projects, but never for major structural jobs that arent getting glassed over or for bedding.
Im a big fan of experimenting with materials and what not, but i would just feel really uncomfortable using something that didnt have that above/below waterline sticker.

 

I mean he used an open male form and stuck all the Corecell together with Gorilla Glue, then glassed the core on both sides at once via infusion.

50+ft catamaran and these were his hulls and bulkheads/beams.

I did the same on my daggerboards because of the number of hours to glue together 26 linear ft of foil sections cut from foam a little over an inch thick.

The rest of my boat is epoxy, but I have also seen this method of bonding foam online. I think you can Google it.

 

I've seen those, but I've always wondered if they can be closed or if once you start a tube then it's all going to go off if left sitting? Are the mixing tips single use only?

I won't speak for the original poster, but for me, designing my own boats is not about saving money, but about having a boat that does what I need it to do. Each boat I build comes with the risk of failure, and not being an engineer or NA I don't know how to figure out just how little I can get away with. As a result, I tend to make things bigger and heavier than they really need to be, and so far it's working.

Sometimes it's not really about the finished product, either. The kayak I'm finishing up now wasn't really ever intended to be finished, but rather as an experiment to figure out how to build cedar strip boats. Fortunately, I figured it out as I went along and ended up with a great result. Sooner or later I'll build one that doesn't turn out so well, and that's OK. That possibility is built into the calculus of the design.

Sooner or later I'm going to build a fat rowboat not because I need a rowboat, but as a learning process for cold molding and a step up to the next project which will be significantly larger. The goal is to build each iteration a bit larger and more complicated until I'm ready to build something in the 42' class which is the final goal. Each one, in addition to being larger, is also more complicated in terms of systems such as propulsion, plumbing, etc.

If it were all about the finished product then, for larger boats anyway*, it would be worthwhile to either buy one or else find a plan that was "close enough" and build from it. Instead, I'm teaching myself boat design and building by trial and error, and learning what I can from looking at how other people do it. The end result is a boat I designed and built, a boat that works well for me, and a step towards building a better one next time.

I guess the big question to ask an aspiring amateur designer is "Can you afford to fail?". Can you afford to build your design and then junk it if it turns out badly and start over? Can you afford, in terms of time, money and energy, to go through a couple of design iterations before you get it right? If the answer is "no", if you can only afford to do it once or can't stand the thought of failing at it, then designing your own is probably not the way to go. I would argue that you will learn more from building a mediocre boat you designed than you will from building a perfect one from a set of plans. Is it about the journey, or the destination?


*Kayaks seem to be an exception. The Raptor has cost me less than half in materials what even a used boat of it's size would. If labor time was considered a cost then the equation would change, but for me the time spent working on it is a benefit, not a cost.