14. Moulding and Casting¶
Group assignment:¶
- Review the safety data sheets for each of your molding and casting materials
- Make and compare test casts with each of them
- Compare printing vs milling molds
Link to group site.
Individual assignment:¶
- Design a mold around the process you’ll be using, produce it with a smooth surface finish that does not show the production process, and use it to cast parts.
3D printing Design¶
The design that I have decided to use is my groupmates, Cooper, that he created for our machine week. This is design that pushes the moles up and down. Instead of re-printing all 5, I thought I would make a mold of one and it will be an easier way. I decided to make the specific gear that the device uses since this is my first time casting.
First Mold¶
There were two molds created in this week because the first one had print line.
Process of 3D Printing¶
This is the size of the gear that I am going to mold.
Then as you can see in the setting that I chose, the A1 printer instead of a mini. I also chose todo extra fine. That is because the mold needs to be smooth meaning that you don’t see the lines from the 3D printing.
This is an image of how long long the gear would take to print in the setting that it has.
This is me uploading the gear to the printer.
After the gear was printed out this is what it looked like.
Pouring My Mold¶
The next step of this process is to pour the mold. The process of this was very simple however, I ended up remolding this because I forgot todo post-processing.
This is the materials that I used for the mold.
This is the directions that I followed to mold. I also studied the datasheet before just to make sure I knew what I was doing.
This is what the data sheet looked like but instead this is the paper version.
These are the two bottles side by side from each other that came out of the box. There was not that much left in them.
This is the molding around my gear right after I poured it.
Taking Out Of Mold¶
The next step was to take my peice out of the mold.
This is the my piece taken out of the container I molded in. As you can see the top is all covered therefore I needed to peel the top part off.
This is the top cut off and the 3D printed piece taken out of the mold.
Casting¶
For the casting I worked with Amalia.
The first step to casting is to mix the two parts together and the video above it us mixing them.
Then above is a video of us pouring into the molds.
This is my mold after I poured into it.
This is my gear removed from my mold. It’s hard to see in the photo but there are alot of air bubbles and 3D printing lines.
Second Mold¶
With the second mold, I decided to improve my first mold by removing the print lines and air bubbled.
Post-Processing¶
For the post-processing of the new 3D printed gear, I decided to use the XTC-3D™. Many people in out lab used this including my group mate, Cooper. Before I used it, I was sure to check the datasheet and make sure I had the right ratio.
This is an image of me gear after lathering it in the XTC. The reason that I have my gear on tape is so that it didn’t stick to the cardboard.
Molding For Part 2¶
This time we ran out of the clear so this time I decided to use PMC™-746 Clear Amber. The datasheet for this one is linked here.
This is my mold just taken out of the cup.
This is my mold with the 3D printed divice removed. I noticed that this mold material I thought was going to be flexable but it was not and made it harder in the future.
Casting For Part 2¶
The next step was to cast.
These two cups are my materials before mixing them together. As you can see it was a 1 to 1 ratio.
Once those were mixed together, the pot life was only 1 min which means that I needed to get the mixture into the mold fast or else it would harden. However, above is an image of the mixture poured in.
This is an image of my mold compleatly hardened. It was ready to be taken out but I soon realized it didn’t want to come out. I think the reason of this is because I didn’t use the spray that makes the mold remove easily. To fix this I ended up just cutting the mold which still took me about an hour todo.
This is the final product of my gear before post- processing again.
Post-Processing¶
When I went to go get the gear checked by my teacher but it didn’t pass yet because I needed to clean up the back ot if. While pouring I made a mistake and over poured. However since tore up my mold I wasn’t able to re cast therefore I decided to do some post process. I sanded down the bottom until there was nothing left and the following picture is the final result.
Reflection¶
Individual¶
This assignment might be the easiest week because It was very straight forward. If I was todo this assignment again I would do an object I would want to kept and I would use the spray that makes the molds remove easily. I would also make sure to stop the pour and not over pour and leave a bad top.
Group¶
The group work was also veyr easy and the nice part was that my group mates used a wax mold for their Individual assignment and so it was easy to compare.