week 9
- molding and casting
- Assignment: design a mold and cast the parts
Going back to hardware, this week subject passes on molding e various types of casting, depending on materials.
For the exercise we have used the Modela milling machine with a 1/8 head's tool and this is a factor which is to be taken in very consideration.
A block of hard wax 90x90x32 mm is the room for our design and it is to preview a 5 mm edges thickness plus the tool's pattern clearance.
The procedure is to mill the wax as a male mold, from this a female soft counter mold to be realized in a silicon bi-componets.
Depending on final materials, the countermold bi-components are different as the metal, to be casted at high temperature, needs a particular wax: Max Mold.
For better results, is important to mix the components slowly to avoid air bubbles. after casting a light knocking on a table of the mold helps the emerging of the bubbles.
Silicon hardening needs 24 hours ad if casting with liquid plasting, you have a first prototype of the object in 45 min.
I designed a kind of Ninja's shackle/multi-tool.
The idea is to have a multi tool made as a shackle with common size hexagonal tools.
I realized the 3d model with Rhino and passed it over the modela machine.
Settin the 1/8 tool but with the 1/32 function for milling it in 3d.
Once the wax qube is milled ( i had to do it 2 times), i put inside the liquid bi-component plastic solution and had to wait for 1 hour to harden.
The result is the famel of the object and very gummy.
Last passage is with the final plastic bi-component which has to be mixed with its catalyzer 10 to 1 in volume and let dry.
The plastic result is very well defined. Maybe for this kind of tool it is better to repeat it in metal, with other materials for casting it at high temperature.
shackle.3dm
By the way I got to use it and is very versatile.