So what is “casting with sand”? Especially when it relates to antique iron beds.
It’s a process whereby a mold is taken of an object , by building a box around the solid object and then packing a dense mud sand mixture into the box that forms around the solid object. On beds this has to be done to either copy existing castings on a bed frame or pour molds around new wooden template’s that are hand carved . That is the manner in which beds were made back in the 1800’s.
An artist would hand carve a design, out of wood, that would then be used as the template for a mold to pour hot liquid cast iron to create the castings on a bed to join the pieces together.
When we hear Sand Cast molds, it’s a little misleading. It’s not just pure plain old sand………. its a mixture of fine sand, some clay, and a small amount of water to make the mixture cohesive. This mixture is called green sand because it is moist, not because it is actually green. The “green sand” is packed into the box that was built around the wooden template or the existing casting that is on an antique iron bed.
Cast iron was then poured into the sand mold. Quite often, back then, new molds had to be made after every frame was poured. Today cast iron molds are used so the repetition of having to make new molds after every bed, is a thing of the past. Whereas it might take as much as a day or two just to fabricate a bed from start to finish…….larger factories today, are able to manufacture hundreds of beds in one day, from from stock to finish product.
Unfortunately along with the innovations and newer production methods come lesser quality . Manufacturers will argue that their iron beds, which are actually aluminum , have all the same detailing as the originals from the 1800’s. That argument falls flat for a couple of reasons. First …… beds today aren’t iron ……….they’re aluminum with steel tubing. No one is making bed frames today out of cast iron. It’s too costly and prohibitive because of the foundries that are necessary to be able to pour cast iron. Aluminum melts at a much lower temperature. Cast iron needs furnaces that are specially designed for the high temperatures needed to melt iron ore.
Another reason products made today with aluminum can’t have the same quality is because of the soft nature of aluminum as oppose to cast iron. Once an frame is poured with aluminum in today’s factories, it then has to go through a sandblasting booth or an industrial roto-blaster. It is of utmost importance that only a minimal amount of time is spent sandblasting the aluminum castings or else a significant amount of clarity and definition is lost. Sort of like a jagged rock that ends up in a river and over years and years become smooth all the way around. That’s a similar analogy to what happens to aluminum castings. That is not the case with cast iron castings, which can withstand any amount of sandblasting and look as good as the day they were poured close to 200 years ago.
Materials make a world of difference in iron beds that were being poured in sand cast molds back in the 1800’s. Although we still have those materials today……. they are no longer cost effective for manufacturers to be able to complete foreign markets and companies here at home that choose to make inexpensive replicas of what man took great pride in producing in the 1800’s.
I hope you’ve found this blog informative . I invite you to revisit my website
to answer any and all questions you might have about antique iron beds.
I also invite you to take a look at our company Face Book page for multiple photo albums on Custom Finishes, Canopy Conversions and a comprehensive “Before & After” King Conversions album.