10. Molding and casting

Group assignment

review the safety data sheets for each of your molding and casting materials, then make and compare test casts with each of them

Materials

• Modeling Wax
  • Ferris File-A-Wax
    • Colour: Blue
    • 92 x 152 x 39 mm
    • Safety Data Sheet & Technical Data Sheet

• Molding

  • Smooth-on MOLD STAR 16 FAST
    • Mix Ratio: 1A:1B by volume / 1A:1B by Weight
    • Pot Life: 6 minPot Life: 6 min
    • Cure Time: 30 min
    • Temp: 450F 232C
    • Color: Blue-Green
    • Safety Data Sheet

• Casting

  • Smooth-on Smooth-Cast 300
    • Mix Ratio: 1A:1B by volume or 100A:90B by weight
    • Pot Life: 3 min
    • Cure Time: 10 min
    • Mixing Tool: metal, glass or plastic
    • Colour: White
    • Safety Data Sheet
  • Low melting point alloy
    • Safety Data Sheet

• Coloring

  • Smooth-on SO-Strong
    • 0.01% - 3% of the total weight (Parts A + B mixed) of the material being cast
    • Safety Data Sheet

Preparation

For this week, we choose 2 materials for comparison: Resin and Low melting point alloy. Before the test, we set a test enviroment for cleanness and safety. Covering up desks with platic bag and newspaper and taping them with the desk.

Then we prepared the following. - Disposable rubber gloves - Electronic scale - Paper towels - Plastic cups - Disponsable wood muddler

Using wood muddler is the tips for this. The instructor told us that plactic muddler would cause a thermal reaction. We decided using a silicone mold which our instrustor made before for this experiment.

Cast

Resin

First, we cast with resin. Openning the windows, putting gloves on both hands and measure Smooth-on MOLD STAR 16 FAST. Put a platic on the electric measure and calibrate. Smooth-on MOLD STAR 16 FAST is consitis of 2 types of liquids. We measured type A first and it timed 0.9 for type B.

Putting another cup and mesured liquid of type B. Then putting type B into A. Muddled gentlly with wood muddler, the cup became hot. At the same time, we stand the mold vertically with cartboard and press both parts with rubber bands. Poured the liquid into the cast.

This liquid is white at the beginning but it turned colourless and transparent gradually. To become it stiff, it took about 20 mins despite of 10 mins on catalog. This might be because it was 10 degree celcius in the room but catalog temperature was 23 degrees celcius.

Low melting point alloy

Second, we tested with low melting point alloy. This is allow melted by 70 degree celcius.

Our first try was melting it with boiled water. This was pertially worked that mean we could melt it but it became solid quickly. Hence it was hard to transform. Then, we prepared an electlic stove. This made transform easier but still took time. So we used a gas burner as well.

We finally melted all and made them transformable. Poured melted alloy into cast which is sand by MDF and pressed by vice.

And we got this. Comparing Resin and Low melting point alloy, Resin is easier to cast and safe though it takes a bit longer to be sold.