week9 : molding and casting

Assingment: Molding and Casting something.

In the process of molding and casting, first we milled a wax with milling machine and we poured a resin to the wax. After wating 16 hours, the resin will become solid and we will be able to use that for casting. To cast it, we poured the silicon to the resin and keep it. Then finnaly we can get what we want. We can use mayn kind of the casting materials for example plastic, silicon and food... And compared to the 3D printer, that is the adcantage of moling and casting. Other adcantage is that once we make a resin one, we can use it many times, so if you wanna make a lot of same 3D models, it will be good.

Milling

To mill a wax, first we have to prepare the 3D model and take care about the size. The height of our wax is 30mm, so the hight of 3D model should be under 25mm. In this time, I didn't make two parts modling, but if we wanna do that, we need to make a molding hole and a air hole. For assingment, I made the Gaudi's dragon with Blender by myself. First, the milling machine mills its model as a rough cut like this.

And the result was like this.

Next time, we changed the diameter of drill and it cut as a final cut. It cut the details of the model. This is the result.

After making the wax, it's time to mold with a sillicon. We used these liquid and mixed it 1:1. To ma ke a good resin solid, we avoid to make a bubbles inside of resin. So we poured it slowly and slowly.

And these are the results. Then mold positive one with a RMC. Actually it didn't work becasue I couldn't get the positive one from the negative one. I'm still not sure why but I guess one of the reason is that I molded it too early for the sillicon to become solid.

So I did it again with the food safe sillicon and chocolate for positive one. First molding with the sillicon and when it becomes solid, I poured the meltgin chocolate to it. Here are the result. It worked but I didn't know that we need to take care about tempreature of chocolate while melting, otherwise the oil in the chocolate removes from it. So the taste was not good. Anyway I can make a chocolate dragon :)

You can download the dragon model for molding and casting from here

.stl