Molding and casting

Welcome to the 13th week. Objectives of the week are:

• Group assigment:

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

  Compare printing vs machining molds.

• Individual assignment:

Design a mold around the process you'll be using, produce it with a smooth surface finish, and use it to cast parts.

Donwloading of the "Leon Hill of Paraguay" STL

As a Geologist I have been interested mold the Chaco hill from the western region of Paraguay called "Leon".

STL downloaded from the terrain2stl website.

Figure 1. The terrain2stl website. The archive can be downloaded here: Cerro STL

Procedure for preparing the Machinable wax

First, for the mechanizable wax, a box is needed for being filled.

Figure 2 and 3. The paraffin and the polyurethane.

So, from the makercase.com website, the box were downloaded and cut with the laser a MDF (.dxf archive available below:)

The free box design can be downloaded here: Box

First, it is needed for the mechanizable wax we should prepare a box for been filled.

Figure 4. Mechanizable wax inside the box

Vcarve and CNC routing

In this part, the stl archive of the hill was setup for exporting to the cnc in a .rol extension.

Figure 5 and 6. The vcarve software and the machizable wax on the sacrifice bed and being routed.

After that, the mechanizable wax were filled by a silicone rubber that can be seen below:

Figure 7 and 8. The silicone rubber filled and the rubber let itself to be cured.

Figure 9. The silicone rubber which was prepared in a 1:1 ratio.

24 hours of have let been cured, the negavive mold is here:

Figure 10. The negative mold made of silicone rubber to be filled by epoxy resin.

The negative mold is filled with epoxy resin and let to be cured 24hs.

Figure 11 and 12. Epoxy resin which was prepared in a 1:1 ratio like the silicon rubber and the negative filled by the epoxy mentioned.

Figure 13. The epoxy resin which was prepared in a 1:1 ratio.

AND HERE THE RESULT!

And the final product from epoxy resin is showed off here XD

Figure 14 and 15 The "Leon" hill.

Final comments

Working with the machinable wax, CNC and silicone rubbers in addition to the epoxy resin must be very meticulous, it takes time to cure these substances, so you have to work very well in the design of the machinable wax and the milling of the material.

Weekly Schedule

Time	Sunday	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday