Gasket
Objective
The core purpose of this project is to acquire skill and proficiency in employing precise measuring instruments and mastering a range of manufacturing techniques. For this project we have been given a metal block and we were asked to manufacture a thin (1/16”) PVC gasket that could perfectly fit on top. As first step I took the measurements of the metal block with a caliper and created a sketch.
Manufacturing
After the sketch I used OnShape to create the 3D CAD model. I then exported it as a PARASOLID file to a CAM software called GibbsCAM. With this I set up the entire CNC milling process, using climbing milling (rotation “in favor” of the 2D endmill motion) to improve the cut of the PVC and obtain a more precise result. Once the file was ready I uploaded it to the CNC mill machine and started to machine the PVC with a 1/4 in endmill. I used a particular tape to avoid the PVC plate to move during the process and at the end I removed all the remaining material remained attached to the piece with a deburring tool.
Simulation with GibbsCAM
Real CNC milling process
Final Result
I am happy with the result because the gasket perfectly fits the metal block (provides a tight seal but also has enough tolerance to fit at the holes) as you can see from the pictures below.
Comparison between prototype and real result.