8. Moulding and casting¶
This week focused on the main concepts of moulding and casting, starting with the group assignment where Abdullah and I did the second material, gypsum, which was researched and experimented with according to certain ratios we chose and followed. More details about our part in the Word document can be found there.
Individual task¶
An individual design with a thickness of less than 15 millimeters and a total length and width of 50-70 mm is designed according to a material of our own choice, and the design was created using Fusion. For my design, I chose to design a Mercedes logo.
Steps of creating the design¶
Note: inspiration of designing the logo was obtained from this video.
Step 1¶
Create a half triangle as shown below.
Step 2¶
Mirror the triangle to get its the full shape.
Step 3¶
Create a circular pattern for two more triangles in 360 degrees.
Step 4¶
Trim the intersectered lines for a clean shape of the triangles.
then click on surface extrude with a taper of minus 60 degrees, and do another surface extrude for a length of 10 millimeters and higher.
Step 5¶
On the side of the shape, create the sketch as shown below for the starting point of the revolve.
Then, click on the front of the shape and draw a full circle.
Step 6¶
Extrude revolve using the sketch and the circle to create a circular fence for the logo.
Step 7¶
Solid extrude the base of the logo.
Step 8¶
Create a chamfer around the corner of the inner circle.
Steps of cutting the design off the wax¶
Roughing and finishing¶
For ths part, a milling machine was used to cut off the parts using a 1/32 inch drill for roughing and a 1/4 inch for finishing which took about 20 inutes and 2-3 hours respectively.
Step 1¶
The individual designs were downloaded from the faablab share email as shown below.
Step 2¶
Select type of milling and whether if the design has flat planes or curved surfaces and if it requires cutting from top only or from the bottom as well.
Step 3¶
Place the drill in the center of the wax piece according to the coordinations below.
Note: the Z axis is determined if slight emissions are created by the drill.
Step 4¶
Check the size of the designs using TinkerCAD as shown below.
Download the design format in STL for 3D print as appeared below.
Step 5¶
Define the size of the wax in length and width.
Note: thickness is 12mm to not drill over the wax.
A toolpath will be created for the machine to follow the structure of the designs.
Step 6¶
Click on preview model to estimate actual size of the designs on the wax.
Note: thickness of the design must not exceed 15mm.
Step 7¶
Click on perfornm cutting to start the milling operation
Note: type of drill size and pin shape is addressed below.
Step 8¶
Click on options, then Surfacing.
Note: The type of drill used for surfacing is different than the one used for roughing.
Depth of surface is shown below and will take approximately 20 minutes.
Step 9¶
define the origin pont on the center of the wax.
Note: Z axis is defined if emitted particles of the wax are visible.
Step 10¶
install the size and type of drill that is recommended before the cutting procedure.
Step 11¶
Select a suitable location for the designs before the cutting procedure begins.
Step 12¶
Click on start cutting, the cutting procedure will take approximately 61 minutes.
Casting the design¶
After creating the mold by cutting the wax, two materials will be used for the casting procedure as the first material will be soft as Silicon which is the mold’s material for extracting the design then a hard material will be casted into the mold as Resin.
Step 1¶
Scale the amount of Resin that will be casted into the silicon mold by pouring water into the mold.
Step 2¶
Before casting the Resin into the mold, it has to be mixed for a few minutes.
Note: Pigment color was added to Resin of both molds.
Step 3¶
After pouring colored Resin into the mold, a duration of 24-48 hours were needed for the mold to be ready.
Step 4¶
Final results are shown below.
Note: the Mercedes logo casting was redone due to final result not fully dried and the apple logo was left as shown previously and not redone.
