Small speed boat mold construction

[ondarvr]

This thread has got me thinking that I need to make a new dinghy, because after 15 years or so the one I made has seen better days. It is going to be about the same size as the old one (8’6” x 3’6”), but I want to modify the bow somewhat.

I’ll start a new thread as I get going on it.

I'm going the other direction. I'm downsizing everything, with on

Impressive Resume, I have no choice but to admit it. Congratulations! You've left me speechless.

My "impression" is that in the longer version you'll tell us about the moment you planned and launched the company to build small plastic boats, thus completing your experience in "the industry," as you call the boatbuilding sector.
For my part, I will end my participation in this thread here. Again, congratulations!

I never really started building boats because after having lived on the water and having been around boats from a young age, plus building them early in my carrier, I learned it was very difficult to make any money owning a boat manufacturering company. There were a few big players that made great money until they went bankrupt. And every week a new wide eyed dreamer would jump into the market with a pocket full money and try to make a new design and sell it for less.

If you did everything right, including your timing going into business, plus had a great plan, you were very smart and the people around you were too, then there was a slight possibility you would succeed, at least for a while.

I did other things where there was less competition and more money to be made with less stress and fewer liabilities.

 

[Tomsboatshed]

I'm going the other direction. I'm downsizing everything, with on

I never really started building boats because after having lived on the water and having been around boats from a young age, plus building them early in my carrier, I learned it was very difficult to make any money owning a boat manufacturering company. There were a few big players that made great money until they went bankrupt. And every week a new wide eyed dreamer would jump into the market with a pocket full money and try make a new design and sell it for less.

If you did everything right, including your timing going into business, plus had a great plan, you were very smart and the people around you were too, then there was a slight possibility you would succeed, at least for a while.

I did other things where there was less competition and more money to be made with less stress and fewer liabilities.

The old adage: How to make a million dollars in boatbuilding? Start with a billion…

 

[rnlock]

Regarding vacuum bagging, it works fine with fiberglass. For a week, I helped a semi-professional boatbuilder using molds and vacuum bagging with foam cores. We were using epoxy. If there was a really slow-setting polyester, and if I could hold my breath for hours at a time, I'd consider using it with vacuum bagging. For people who can set up leakless vacuum bags (not me), there is vacuum infusion, which apparently improves the resin ratio even more. This, presumably, reduces the thickness of the layup even more, but a bit more fiberglass could be used to make up for it. We were making fiberglass "wakeless" launches. I think they're mostly used for coaching crew, but maybe if I lived in Florida on a canal I'd want one so I could go 15 mph without splashing the neighbors docks or eroding the shore much. I think he may even have made money doing this. A niche market may be the right sort of thing for a guy who wants a small business. He wouldn't have to compete with the huge economies of scale available to those with deep pockets who produce thousands of examples of any one design. It's hard to get rich that way, though.

It probably makes sense to make the first boat with wood. If it turns out well, it might be used as a plug for a mold. There are a bunch of designs which are quite small to work from. As I recall, either Glen-L or Clark Craft has a plan for a tiny, nine foot runabout with an inboard engine. However, they are talking about a 250cc, two stroke motorcycle engine. I think there's another one, for kids, that's even smaller. A glass version would probably be significantly heavier unless it used a foam core or some carefully designed framing inside. Maybe hat sections with some tow or uni on top. Thomas Firth Jones, in his essay on his Tuckahoe Catboat*, says that he thinks it may be worth it to make molds if four or five hulls are produced from them. I suspect that his molds are less elaborate than the ones used for mass produced boats. He has some other interesting comments about fiberglass, and about people shopping for fiberglass boats, in that essay, not all positive. Back in the late 1920's, Lockheed was using concrete (!) molds for some of their molded wood fuselages. I think this was before there were suitable glues for cold molding, but if so it must have taken a long time to warm up the concrete for hot molding. Something tells me these molds weren't very portable, but maybe they would be in ferro-cement. I'm guessing such molds could be useful for fiberglass. I think Fairey, a British aircraft company, made some well regarded hot molded boats, using birch they had left over after WW2. I wonder what their molds and their process were like. Fairey Marine history

*From his book Boats to Go. The Tuckahoe Catboat looked like a typical catboat, and was rigged like one, but the hull was very different. Apparently, it went very well. Another book of his, New Plywood Boats, has a bit of discussion of molds and of the boat building business.