using wood for molding the fluke???

[Robynn]

So since clay is expensive as idontevenknow, my mom got the idea to make the fluke mold out of wood and then pour plaster over this. I am aware this would be very difficult since ofcourse wood is difficult to shape but I would be up to the task. Anyone knows if this could work or not and why would and wouldn't it?

[mersheep]

I have been considering a wooden fluke mold for some time now.

Wood is not difficult to shape. It is actually historically one of the easiest materials to shape through carving, filing and sanding. Unlike clay wood is self supporting. No armatures are needed and it does not drift or slip under the molding pressure. Wood can be built up like clay by gluing sections together then sanded down to match.

The best wood to use for carving is called basswood. Available in most craft supply stores. Wood can take on a detail unparalleled to that of clay, which distorts or changes shape in the firing and drying proceses. Think of those sculptures of mermaid shaped figureheads on ships. Some detailed down to the hair on the head, and the stitching on the drapery. Also think that most boats were made of wood, and the complex shapes that entails. Even metal ships like the Titanic were made from wooden patterns.

Wooden molds for centuries have been used for the process of sand casting metals. Damp sand is packed into a box called a flask which is hinged. The flask is opened and the wooden pattern is removed. The sand retains the shape. Hot metal is then poured into the flask. While I would not recommend sand casting rubber, I have always thought wooden patterns would be ideal.

There is also an advantage to using wood as companies like Decorators supply sell wooden applique, which are the very swirly and shell shaped designs so popular in the 18th century. You can get these pretty much off the shelf. Glue them on and have a pattern in no order of time.

[mermaidrobynn]

That's actually super interesting, thank you for the information!!

[PearlieMae]

It's an interesting idea, if not hugely labor intensive.

However, using an oil based clay is easy peasy, it's inexpensive and reusable, and the level of detail attainable is at least as easy as carving wood, if not easier, in my opinion. Plus, you don't have to maintain the clay's moisture while sculpting, it doesn't need to be dried nor fired, and acts as its own release when making a resin mold.

Basswood is nice and soft, easily carved and, like you said, is self supporting and durable. Not too easy to correct a mistake, though. And extracting a wood master from a plaster mold sounds like a recipe for disaster, to me. Neither are pliable. If you're making something soft, make a rigid mold, if you're making something rigid, make a pliable mold. Wood against plaster, the plaster is going to shatter.

Also, you'll lose detail in the wood carving when you seal it, which you'll need to do if you pour plaster on it.

I'd like to see a prototype to prove me wrong, though.

[mersheep]

Were I to carve a mold I would probably carve it in negative, so that the rubber is cast directly into the wooden mold. Probably a bit more advanced than I personally have time for.

Typically patterns are not made from a single piece of wood. Rather they are rough build up then shaped down. This way the grain of the material can go with the flow.

For a quick buildup I still think some of the applique from Decorators Supply could jump start a project. They have quite a selection of shells. A quick look at the Stair brackets and one can see swirls on a fluke.
http://www.decoratorssupply.com/store/main.aspx?p=CategoryMasterBody&c=CR

The basic bottom board could be simply cut out and the applique glued on. The wooden pattern would be sectional. The pattern could be made to fit together like a Chinese block puzzle. Like how shoe lasts can come apart to be removed from the shoe. One would also have to watch out for undercuts. Although with a system of dowel pins the sections could be removed largest to smallest.


I think the OP was not able to find the right sort of oil based clay that they could afford. As most sculptures oil based clay it for flukes and scales, there is some advantage to starting with the tried and true methods.

[PearlieMae]

Good points, all! I'd love to see it in practice. I'm good, but not nearly talented enough to carve a fluke in relief!

Here's a fluke I currently have in progress...maybe three pounds of plastilina (under $20 total).

40471

[Mermaid Wesley]

I can see it being really cool! I know that i am awful at working in negative though. I tried to sculpt a starfish in negative the other day and it was HARD.
The other reason I like clay is because I can eyeball it, add, subtract, add subtract, squint, shave off pieces, over and over. I'm indecisive.

[Azynza]

Good points, all! I'd love to see it in practice. I'm good, but not nearly talented enough to carve a fluke in relief!

Here's a fluke I currently have in progress...maybe three pounds of plastilina (under $20 total).

40471

That is incredible PearlieMae! Wow!!!