Playing in the Sand

Tooling-Up for Cavity Molding...

Playing in the Sand, and re-thinking Molds

Slowly I'm getting closer to actually using this stuff.

I should have had my camera with me the day I moved the bench to the foundry... Or more accurately I should have measured the doorway before even beginning the bench itself.

The door, wall trim and even the door frame itself had to be removed to get the damn bench into the room.

Once in place, I riddled 100lbs of the sand into 2 of the 3 compartments.

This is exactly what the sand looks like once riddled.

It's very bizarre and unlike anything I've ever seen before. It looks strange, feels strange and behaves strangely.

The room was at -15C when I riddled the sand and it seemed just as pliable as the day it was -3C earlier the week prior.

This is the primary reason that I shelled out the bucks for a chemically bonded sand, as it would have to be stored in a dry but unheated area .

This is the standard "Sand Sausage" temper test.

A handful of sand is squeezed into a sausage, and the strength of it's binding is judged by breaking the lump between your thumb and fingers.

For me this is quite meaningless, as I have no reference whatsoever to gauge against, and hope that what ever the sand's binding properties are, is good enough.

This is a 5lb bag of pure cocaine, that I use to keep me on the edge, and work round the clock for days on end...

As Coke is so plentiful, I'll be using it as my parting compound, between the Cope and Drag.

I've no idea what the chemical composition is of this powder, but it is commercial "Parting Compound."

This is a rough cloth bag that I guess is cotton, and has a pronounced loose weave in the fabric to allow the Parting dust to exit through.

At this point I've been trying to visualize how I'm going to use all this new stuff...

I've found a few cement encrusted trowels that I've cleaned-up, cut up a series of plastic pipes that have a slight taper for sprues.

Bear in mind that once I actually make a few molds in the sand I'll look back and see how ill conceived my notion of cavity molding was prior to actually doing it.

I wanted to make few permanent Gate fixtures that I could place adjoining to the pattern.

The idea was to turn down a chunk of wood, rip it in half, and it would sit flat on the molding board along with the pattern.

If it doesn't work out, then I still have the firewood, where as if I'd cut a section from my wife's kitchen mop, the consequences may have more far reaching effects.

This is wooden pattern cut into 1/4" flooring mahogany. The intention was to make a pattern that could withstand numerous molds being made.

The pattern is painted with a high contrast paint to offset the lacquered finish, in case I just can't get a reasonable casting.

My nephew will not be without the guiding influence of his eccentric uncle...

This is one of two foam patterns for the Baran-Harper Group.

The cut pattern has been coated with an oil-based enamel paint, and left to cure on a rack located on the wood furnace.

A second coat of High Gloss urethane was applied, and similarly cured.

My hope is that the foam will have sufficient mechanical strength to be rammed into a mold and extracted a few times...

Again as I'm anticipating a few malformed pours initially.

As nice as it would be to have both of the above patterns mold and cast perfectly, I would feel uneasy that somehow it was a fluke, and be wary until I ran into a series problems with the typical struggle that accompanies any new endeavor.

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