FAQ

What things can be cast in white metal?

What metal is used?

How does the casting process work?

What about shrinkage with metal casting?

Is spin casting cost effective?

What about plating and metal finishing?

How much time is needed to cast something in white metal?

What things can be cast in white metal?

Centrifrucal or spin casting with lead-free pewter and zinc is relatively quick and quite affordable. A quality casting model is required, which can be any existing object or a newly designed form. Generally the size limitations are 8” long, 4” wide, and 2” thick, although an object with all those dimensions would be difficult and quite expensive due to the cost of the metal and the need for special production techniques.

The most typical spin casting metal molds are for products that measure less than an inch in cross section, and 3 or 4 inches, or less, on the diagonal or diameter. Such objects can be cast in multiples, which greatly speeds up production time.

SThe casting model should be made from metal or special casting clay. Plastic or wooden models will not withstand the mold production process.

What metal is used?

Bayview Casting & Design most often uses lead-free white metal, which is primarily a tin alloy. It is sometimes referred to as “pewter”, which in today’s world is a misnomer. White metal is hard but easily machine when required. It can be finished to a bright, slivery surface or oxidized to create a dark gray color with darker highlights. It is also easy to electroplate with other metals such as brass, copper, or bronze.

Zinc is a much harder metal, and can be used for parts that require extra strength. It is less expensive than lead-free tin alloy but it requires more expensive molds and is difficult to electroplate. Please inquire about metal casting with zinc as it not recommended for most art metal production.

How does the casting process work?

Objects to be cast are first fine-tuned for detail as every nook, cranny, and potential flaw will be captured in the mold. Next, the object is carefully “sunk” into a soft rubber disc which is then vulcanized under heat and pressure, and which produces a hard rubber “model mold” that retains an exact three dimensional image inside. There is some shrinkage, but on smaller objects, this is usually inconsequential.

Orders can be filled by casting from the model mold one object at a time. For larger orders, multiple pieces from the model mould are sunk into a second mold, which results in a “production mold” that now yields 3, 4, or even 7 or 8 pieces from each casting cycle.

The rubber mold is spun at a high RPM and molten metal is poured into the center hole. Centrifugal force drives the metal into every crevice and design detail.

Once removed from the metal casting mold the freshly cast objects are sent to the polishing room to be cleaned and made ready for their final finish or any necessary machine work.

What about shrinkage with metal casting?

Every casting process results in some shrinkage. To minimize these changes, newly created models should be made slightly ojversize. Experienced production people can often help mitigate shrinkage issues for customers with reproduction projects.

Is spin casting cost effective?

The cost of a metal casting project will depend upon the number of molds required, the amount of post-casting finish work required, and most importantly, the cost of the metal needed to create each cast metal object.

Bayview Casting & Design normally charges a $150 mold fee which covers a model mold and a production mold if necessary. Small castings usually cost $7-$15 each with your choice of finish. The price of metal often fluctuates weekly but we will determine the cost before we begin the design and production process. Other cost may include design fees, extra finishing steps such as machining parts or assembly, or personalization, such as engraving.

What about plating and metal finishing?

Electroplating is an art and we are fortunate to still have some old time companies in our area who provide excellent finishing services are reasonable costs. BCD offers four standard finishes: antique brass, antique bronze, antique pewter, and oil rubbed bronze. We also offer nickel, copper, and custom colors at a small premium. Our years of buying and selling antiques has taught us that the right color, especially on the little details, is what makes design project really come together.

We can provide antique pewter (or bright pewter) from our production room. Otherwise, the plating process requires a week to 10 days, depending on production schedules.

How much time is needed to cast something in white metal?

Making a casting model can be quick or require a lot of time and effort. Once the casting model is in hand, the mold can be made in a day or two. Spin casting is efficient work, so orders of several hundred pieces can usually be finished and plated within 3 weeks. Smaller orders can often be expedited.

Follow the link to read more about Custom Metal Casting.

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