This video demonstrates two methods for creating custom metal ingots and ingot molds at home. The primary focus is on crafting durable iron ingot molds by melting scrap cast iron (from weight plates) in a homemade microwave kiln. The process involves 3D printing a PLA plastic pattern, creating a sodium silicate-bonded sand mold around it, burning out the plastic, and then pouring the molten iron. The newly created iron molds are then used to cast aluminum and brass ingots.
As an alternative, kiln-free method for hobbyists, the video details how to make custom ingots (with text) using plaster of Paris. This technique uses a 3D-printed hollow shell as a mold for the plaster. The plastic is subsequently removed by gentle microwaving, and the plaster mold is thoroughly dried in a conventional air fryer before being used to cast lower-melting-point metals like zinc. A safety demonstration starkly illustrates the dangers of pouring molten metal into improperly dried, wet plaster molds.
Crafting Custom Ingots: From Microwave-Melted Iron to Kiln-Free Casting
00:00:40 Creating the Sand Mold: The process begins by 3D printing a pattern in PLA plastic. This pattern is then used to create a sand mold, with the sand being mixed with sodium silicate to act as a binder.
00:02:35 Microwave Curing and Burnout: The sand mold is cured in a microwave, first on a low-power defrost cycle to remove moisture, and then placed in a microwave kiln on a higher-power cycle to completely burn out the embedded PLA plastic pattern.
00:04:08 Casting Iron Molds: Using the microwave kiln, 350g of scrap cast iron from broken weight plates is melted. The molten iron is then poured into the prepared sand mold to create a durable, reusable ingot mold.
00:06:23 Mold Integrity: The creator notes that sand molds often crack after the hot metal is poured, but this usually happens after the iron has solidified. He briefly discusses experiments with reinforcing molds using aluminum foil and steel ties.
00:09:45 Casting Ingots with the New Molds: The newly made iron molds are demonstrated by casting ingots from scrap aluminum (from an old lamp) and brass. This highlights the primary purpose of ingots: converting bulky scrap metal into a clean, compact, and easy-to-use form for future projects.
00:15:47 Alternative Kiln-Free Method: A method for creating custom ingots without a kiln is detailed. This involves:
3D printing a thin, hollow shell of the desired ingot, including text.
Using the shell as a mold for plaster of Paris.
Gently microwaving the set plaster to soften the plastic shell for easy removal.
Baking the plaster mold in a standard air fryer (e.g., 5-7+ hours at 230Β°C) to completely remove moisture.
00:19:47 Safety Warning: A crucial demonstration shows the explosive danger of pouring molten metal into a wet or improperly dried plaster mold, as the trapped water rapidly turns to steam.
00:21:08 Casting a Custom Zinc Ingot: The kiln-free method is completed by melting zinc in a simple metal can and pouring it into the air-fryer-baked plaster mold, successfully creating a custom ingot with raised lettering.