Building a Plug/Mold

Eastporter

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I'm interested in the whole boat building experience. Does anyone have knowledge of how to build a plug/mold. I know many of these DE boats started out as wooden boats and then molds were made in the 1960s or maybe earlier to take advantage of fiberglass. Please share photos and stories if you have any.
 

Matt Is Back

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From my quick research, you need to build the hull out of wood, fiberglass it, wax it, then re fiberglass it. After you re fiberglass it, it will harden and you will then get a mold. Proper procedure is a must and it seems easy to mess up. Looks like a lot of work but great satisfaction.

Please correct me if I made any mistakes, Im open to criticism.
 

Eastporter

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Thanks for the reply. It seems like a lot of work and that's why many of the current molds have been sold and resold to different builders.
 

F/V First Team

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From my quick research, you need to build the hull out of wood, fiberglass it, wax it, then re fiberglass it. After you re fiberglass it, it will harden and you will then get a mold. Proper procedure is a must and it seems easy to mess up. Looks like a lot of work but great satisfaction.

Please correct me if I made any mistakes, Im open to criticism.

Basically

But if we told you all our secrets, then it would ruin the magic now wouldn't it? :D
 

ltdann

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From my quick research, you need to build the hull out of wood, fiberglass it, wax it, then re fiberglass it. After you re fiberglass it, it will harden and you will then get a mold. Proper procedure is a must and it seems easy to mess up. Looks like a lot of work but great satisfaction.

Please correct me if I made any mistakes, Im open to criticism.

One of the magic tricks is you have to wax the plug more than once
maybe even 3 times
 

Eastporter

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Thanks for the comments. I think it is clever when I see the male/female sections on a split hull. Is that added by fiberglassing those custom pieces onto the plug? They seem to fit together perfectly and then the keel is built up with 7+ layers of glass to fill the void and connect the two sides of the hull. Anyone here know if they used thickened epoxy in the male/female section or not? I think I saw this on the WESMAC mold but I could be wrong.
 

F/V First Team

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Wax-On-Wax-Off-2358768724dbf64c84ee8a434572392-327-5552-largepreview.jpg

That's about right
 

Eastporter

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The male/female parts are not part of the hull, just part of the mold?
 

Eastporter

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I just looked at your build process/molds again on the photos of the 38'. Thanks for posting- it looks like the layup stops before you get to your male parts. Let's hope! LOL
 

F/V First Team

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Female mold produces male parts. A male plug produces a female mold. Split molds are aligned with male/female nubs positioned on the mold flange. Think of how a cupcake comes out of the cupcake pan, same principle (and for some molds, the same parts used to produce them). Please do not put any epoxy on any parts of these molds/products while they are being created.

Clean mold, wax, buff, wax, buff, wax, buff, double wax, buff, wax and buff some more, then think about starting to layup a unit. And you better not wear anything with exposed metal buckles or anything foolish like that either.
 

lobstercatcher

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Female mold produces male parts. A male plug produces a female mold. Split molds are aligned with male/female nubs positioned on the mold flange. Think of how a cupcake comes out of the cupcake pan, same principle (and for some molds, the same parts used to produce them). Please do not put any epoxy on any parts of these molds/products while they are being created.

Clean mold, wax, buff, wax, buff, wax, buff, double wax, buff, wax and buff some more, then think about starting to layup a unit. And you better not wear anything with exposed metal buckles or anything foolish like that either.

Cupcakes? Thats a new twist.
 

Eastporter

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Female mold produces male parts. A male plug produces a female mold. Split molds are aligned with male/female nubs positioned on the mold flange. Think of how a cupcake comes out of the cupcake pan, same principle (and for some molds, the same parts used to produce them). Please do not put any epoxy on any parts of these molds/products while they are being created.

Clean mold, wax, buff, wax, buff, wax, buff, double wax, buff, wax and buff some more, then think about starting to layup a unit. And you better not wear anything with exposed metal buckles or anything foolish like that either.

Thanks for your thoughtful reply. I was being serious, but I see the humor in the post.
 
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