A Peltier cooler was built but when it was complete is did not work.
Later investigation learned that several Peltier elements were defect or had a poor performance.
Half of the unit in parts.
On the left we see a heatsink with two fans mounted on it. (later I found that the blue finger protection shield was restricting the airflow substantially).
The blue plate is 8 mm thick anodized aluminium with 5 Peltiers of 40 x 40 mm. Two aluminium tubes were glued throug-hole to let waterin and out.
To the right the water channel, laser cutted out of acryl plates Two 6mm thick parts were glued together.
Now imagine a second gasket, a second 8 mm thick alu-plate, this time without water tubes, 5 other peltiers and a second heatsink with fans.
The whole thing tightened with a lot of screws and electrically connected to a 12 Volt 42 Ampere power supply.
The complete unit.
And some detail. We can see that the water channel consists of two layers of polyacryl.
OK, this was a disappointment, but maybe we'll give it a second chance with new Peltiers, tested in advance.