Vacuum Forming
Objective
Exploration of the vacuum forming process and its effects on thermoplastic materials.
Results
Vacuum Forming Plastics Lab Data
Face# ............Temp(F) .............Time in Oven ...............Remarks
1 ........................290 .......................19 sec .............................abort
2 ........................295 .......................20 sec .............................OK
3 ........................286 .......................20 sec .............................bad part (operator error)
4 ........................283 .......................20 sec .............................good part
5 .......................276 ........................20 sec .............................bad part (cool around edges)
6 .......................269 ........................20 sec .............................good part
7 .......................262 ........................20 sec .............................bad part (not hot enough)
8 .......................258 ........................20 sec .............................bad part (not hot enough)
9 .......................253 ........................20 sec .............................bad part (not hot enough)
10 .....................258 ........................20 sec .............................bad part (not hot enough)
11 .....................267 ........................20 sec .............................good part
12 .....................275 ........................20 sec .............................good part
13 .....................276 ........................20 sec .............................good part
The Following Depth Measurements in Inches Were Taken
Face # ....................Between the Eyebrows ............................Midway Down The Nose
2 .......................................1.177 ...........................................................1.525
4 .......................................1.20 ..............................................................1.48
6 .......................................1.28 ..............................................................1.53
11 .....................................1.29 ..............................................................1.55
7 .......................................1.36 ..............................................................1.43
8 .......................................1.29 ..............................................................1.25
Discussion of Results
The vacuum forming process consists of heating a sheet of thermoplastic material until it becomes pliable. After it is heated, the sheet is placed over a mold and suctioned onto it by pumping out the air beneath the sheet and creating a vacuum. If done correctly, the sheet will take the form of the mold and cool immediately after doing so. By keeping our heating time constant and incrementally increasing the heating temperature, we were able to observe the effect on the final mold.
As can be seen from the data of depth measurements, the general trend is for less deformation as temperature decreases. This is because the plastic sheet cools quicker and resists the vacuum pressure before it can conform to the mold. The graphs of the depth measurements with oven temperatures can be viewed. Graphs comparing the thickness of the sheet with average height and oven temperature could not be displayed due to lack of data.
