The following days we were testing the material and optimizing some details. The final prototypes are made of 6mm polyethylene in natural white. Other colors are more expensive and are only feasible in bigger quantities. To avoid the transparent look we are currently working on a logo and a sticker plot for the outside of the main pot.
The process to adjust all parts to fit perfectly together was tricky. After deep-drawing the plastic is shrinking some percent. The model makers had to experiment a couple times to adjust the molds to the shrinking.
And finally the lid was produced in the end. On one picture you can see the positive mold with a metal handle. For better grip, we included a small rip around the handle. The small rip is just big enough to improve the grip of the handle and small enough for easy demolding.
On the last picture you can see how light one toilet unit is (pot+seat+lid): only 3 kg !