Molding and casting
For this week we have to :
Test the modeling process and make some part out of resin or castable material. We tested the old material we had in the lab, because our order isn’t arrived already
So here is the process we use : 3D print original model Mixing the silicone Get rid of the bubbles Cast the mold out silicone mix Wait for the mold Wearing PPE Mixing the resin Pouring the resin into the mold Waiting for the rein to solidify
First ! Safety ! We took a pair of hermetic gloves and goggles, and we wear a gas filtering mask. It was uncomfortable but safe :)
With used an old silicone, and we let it to long in the mixing pot. As a result it was too viscous to poor efficiently onto our part…
We successfully achieve to create silicone !!
I use an old model I had from my robotic team. It is a bottle opener using our logo ! I sliced the part using cura, and print it using my own 3D printer in PLA (Creality Ender 3)
Here is the resulting part !
Now let’s create the silicon mold… We found an old rest of silicon pot, which was surprisingly great !
Here is the part A
And the B
We used plastics cup to mix the silicone
This material require an equal amount of part A and B, but this is not always the case ! Check the datasheet !
We mix gently the mixture while avoiding bubble using a wooded coffee spoon
After the mixing process we tapped the mix to let bubble escape.
When the mixture is homogenous, we pour the liquid silicone into the cardboard box, very carefully. We poured the mixture into a corner and let the silicone cover the part. Do not cover the part from the center because you won’t let bubble escape the part.
Here is the result ! We wait 30 min for the silicon to take and wow ! It works very well !
We tested the resin on an existing mold. It worked, but the mold wasn’t very good, the joint between the two part wasn’t very smart and is difficult to remove when solid…
I poured the mixed resin into my mold. After the recommended time, the old resin remain squishy… We supposed it is due to the low temperature outside. But it solidifies when we warm up the parts inside the lab.
Here is the final result !!