Material Verification
As with all of our projects, we used our advanced metrology equipment to verify that we had the right material. This is especially important for medical devices that must pass rigid FDA guidelines.

CNC Milling Services
First the parts were roughed out using a combination of CNC milling and turning.The separator screen was rough milled on our 5-axis CNC milling center, which allowed us to machine all of the beveled faces on the grid very quickly.

CNC Turning Services
For the main reservoir, we turned the large plastic blank down on the lathe, while also boring out the central hole.CNC turning centers have moveable turrets that can also machine inside diameters with undercuts, using “live” tools that rotate independently of the main spindle.

Annealing
The first pass on the machine established the major dimensions of the part, but it also left behind a rough surface finish with clearly visible tooling marks.This is actually what we want, because our purpose was to first remove as much mass as possible. The displacement of this material creates stress in the walls of the container that must be relieved.

After rough machining the parts were annealed, or heated and cooled in a controlled manner. Here the water was brought to boiling and then allowed to cool back to ambient room temperature. This relieves the stress so the part won’t crack after repeated heating cycles while in use.After annealing, the parts were then re-mounted onto the lathe for final turning.

Finishing
Once the final dimensions were verified, the surface finish was given a high gloss in our model shop.We used a black marker to indicate areas that still hadn’t been touched up yet.After fine sanding, we further improved the surface with polishing and buffing to achieve optical clarity.A gloss finish is good not just for cosmetic reasons. Smooth, glass-like surfaces are easier to clean and will not trap biological material used in this medical application.