Translations:PartDesign Bearingholder Tutorial I/23/en

The only two important dimensions in the sketch are 3mm of machining allowance at the bottom, and a inner diameter of 78mm: 68mm for the outer diameter of the sealing ring + 2x 5mm wall thickness. Since the sealing ring on the other side will only have a diameter of 55mm, the cut-out can be 65mm here.