​Metal Casting with ComposiMold Mold Making and ComposiStone Hard Plaster

Posted by ComposiMold on 17th Jun 2022

​Metal Casting with ComposiMold Mold Making and ComposiStone Hard Plaster

Metal Casting with ComposiMold Mold Making and ComposiStone Hard Plaster

Yes, ComposiMold Reusable Mold Making Material and ComposiStone Hard Plaster work great to make metal jewelry making, DIY fishing lures, toys, figurines, or other metal casting. And the nice part about it is you can continue to re-use the ComposiMold for lots of different molds and experiments. Here’s a video where we made a tin casting where we discuss the process for making a lost wax process.

In terms of wax for the casting, you can use the ComposiMold or wax. I like beeswax because it has nice texture, relatively low melt temperatures, and smells nice. You can also use ComposiMold to make a mold of ComposiMold J And not use wax at all: here’s us making a casting that way. 

Other waxes will work also, just try to keep the wax temperatures below about 150 F when pouring into the ComposiMold mold. Chill the ComposiMold mold if necessary. If you want to use the jewelry wax, use the ImPRESSive Putty to make the mold instead of the ComposiMold, and that will handle the higher wax temperatures better than ComposiMold.

Metal Casting Options

Tin and other low melt metals are ideal for home castings.

If you want to do aluminum casting, gold castings at home, or DIY silver castings, then you will want a way of melting the metal. Here’s the melting temperatures of different metal casting options:

Melting Temperatures of Common Metals

  • Aluminum: 660°C (1220°F)
  • Brass: 930°C (1710°F)
  • Aluminum Bronze*: 1027-1038°C (1881-1900°F)
  • Chromium: 1860°C (3380°F)
  • Copper: 1084°C (1983°F)
  • Gold: 1063°C (1945°F)
  • Cast Iron: 1204°C (2200°F)
  • Silver: 961°C (1762°F)
  • Zinc: 420°C (787°F)
  • Lead: 328°C (622°F)
  • Tin 232 C (450 F)

HOWEVER, now here is the warning: Getting to these high temperatures of some of these metals is difficult and potentially dangerous. A furnace, kiln, or high temperature oven is recommended. You will not be able to melt metals other than the low temperature metals such as tin, lead, zinc, and others in your home oven. You might be able to use a propane torch directly onto some of the higher temperature metals to melt, but you should use some sort of high temperature oven, either propane based or electric.

Another option is to experiment with silver jewelry is with polymer metal clays. Here’s a link to a store that works with us . The shapes can be pressed into ImPRESSive Putty molds to before firing using a propane torch or small furnace. This might be something to explore for you.

When using the ComposiStone plaster mold and casting, be sure it is completely dry. After giving it days to cure and dry, heat the mold to above 250 F for at least an hour. If moisture is in the mold when a very high temperature metal is poured into it, there’s a chance the plaster mold will crack or possibly shatter.

Frequently Asked Questions about Metal Casting Using ComposiMold:

1. Can I do use ComposiMold to make home Silver or Aluminum Castings?

Yes, with care you can make silver casting in ComposiMold as long as you have a furnace that can get up to at least 1800 F. 

2. Even at this high temperature, the ComposiStone should be able to withstand the higher temperatures of the higher melt metals?

Yes, as long as it is fully dry so the moisture does not expand and put undue stress on the ComposiStone Casting.

3. What are the easiest metals to cast with?

The easiest metals are the low melt metals such a Wood's Metal or others with Bismuth in ithem. These low melt metals can be used in the ImPRESSive Putty directly. Here's an example of our metal casting a toy hand.

What other questions do you have? Let us know.