Molding & casting / 06.03.2013

A refrigerator magnet for my mother For this practice I have worked in two different models. The first model is an evolution of 3D printing  practice from the model generated in Rhinoceros (dario01molde.3dm). So, I prepared the model for divide it into two parts that I can support routing with four pins and a little  hole where the material easily introduced. The other model comes from my ancien fondness for travel, when I was a father and could not, with  my wife, visiting different places. From each of these places I brought my mother a refrigerator  magnet. So, my mother's refrigerator was increasing his collection and when I visit my mother I  remember when I could travel.  Then I thought that since I travel every Wednesday to almost everyone this time would be I who make  a refrigerator magnet to give to my mother. And this is my magnet design that also want to use it a lot  in design Fab Lab Sevilla. On Monday I had two models and also prepared recently, so I decided to make the first magnet and I  could give several co-workers. The magnet design is simple, very simple. It is made of rhinoceros on the advice of my friends, they  always have good ideas (fridgemagneto.3dm). First, Jose Buzón cut into pieces wax block with a saw. He has been very accurate and uses the  material very well. Then, in the Modela3 equals the surface I to prepare the machinable wax block  with my design.  Meanwhile, each partner was careful to collect all the chips and shavings of wax for recycling. We  tried to heat it with water. But the best result was with an infrared lamp. We keep trying. To cut my design I have chosen the Alaris FR180, a milling machine simple since we began Sevilla  Fab Lab. Between the roughing and end milling the piece has taken about 4 hours. When the piece is finished I have prepared the silicone rubber mold serving and have poured  carefully. For the design, I've noticed that the mold walls are low, so a wall MDF auxiliary I managed to  raise the height of the walls.  We bought a local version, (Silicona para moldes "Roma /16-Azul" plus a  catalyzer sprecific for this silicone "Catalizador Roma/16-A)  But I need more time, I was the last to make the silicone mold and not yet ready for use. But I will stay on Tuesday afternoon waiting ... For class on Wednesday I hope to have stuck the magnet on the Fab Lab and everyone to see. Attached I finally finished practice. Perhaps it is better to say that the piece has been dried. I have failed with the proportion of silicone and liquid accelerant, perhaps because I have been not weigh it correctly. For best results first I weighed the liquid accelerant and then I added the silicone. It was much better. Another problem has been that the silicone mold has exited with bubbles. I will have to improve. For the piece I used polyester resin and the resin've gotten into a magnet for him to be inside her. This is the result. The references for the materials that i have used are the following: Machinable wax:: Inventables Later on we have found machinable wax in several places in Barcelona, but as we decided to order the FR1 boards from Inventables, i took advantage of the shipping. The recommended materials, that we will try to use in next tests are: Oomoo [silicone] and Drystone or Hydrostone for casting. Software: Rhinoceros 4 SR9, Vectris V-Carve Pro; studied: Modela Player 4 Hardware: Alarsis FR180 CNC milling 2.5 axis machine; Roland MDX-3ºº [wax surface preparation] Materials:: Machinable Wax [Inventables], "Roma 16A" silicone rubber + catalyzer, Acrylic Resin Sumbeart C-300 [Sumbeart, Sevilla] Some conclusions  Time, I need a long time to make the molds. All we have done the whole job one after another. That  means we have not optimized the time.