In this video we take a closer look at the iso-tolerances in connection with the joining of two components. This is then referred to as fits. There are three types of fits (also called seat types or fit characteristics): clearance fit, interference fit and transition fit. With a clearance fit, the tolerance field of the shaft is completely below the tolerance field of the bore. There is a minimum clearance and a maximum clearance. With an interference fit, on the other hand, the tolerance field of the shaft is completely above the tolerance field of the bore. There is a minimum interference and a maximum interference. With a transition fit, the two tolerance fields overlap. The transition fit can have both a small clearance and a small interference. There is therefore a maximum clearance and a maximum interference. We get the minimum clearance if we make the bore as small as possible and thus produce it at the minimum size, while the shaft is as large as possible and thus we produce it at the maximum size. To get the minimum clearance, we subtract the maximum dimension of the shaft from the minimum dimension of the bore. We get the maximum clearance if we make the bore as large as possible and thus produce it at the maximum size, while the shaft is as small as possible and thus we produce it at the minimum size. To get the maximum clearance, we subtract the minimum size of the shaft from the maximum size of the bore. We get the amount of the maximum interference if we make the shaft as large as possible and thus produce it at the maximum size, while the bore is as small as possible and thus we produce it at the minimum size. To calculate the maximum interference, we subtract the minimum size of the bore from the maximum size of the shaft. However, it should be noted that, unlike clearance, interference is usually given as a negative value. In this case, the maximum interference is not calculated as the difference between the upper dimension of the shaft and the lower dimension of the bore, but exactly the other way around, i.e. as the difference between the minimum dimension of the bore and the maximum dimension of the shaft. The larger value is subtracted from the smaller value and you automatically get a negative value for the interference. We get the amount of the minimum oversize if we make the hole as large as possible and thus produce it at the maximum size, while making the shaft as small as possible and thus producing it at the minimum size. To calculate the amount of the minimum oversize, the lower dimension of the shaft must be subtracted from the upper dimension of the hole. However, to get a negative value for the oversize here too, we reverse the values ​​and subtract the maximum dimension of the hole from the minimum dimension of the shaft. 00:00 ISO tolerances (tolerance class, basic tolerance grade, basic dimension) 01:35 Determination of dimensions and limit dimensions 02:36 Schematic position of tolerance fields 03:53 Clearance fit: Calculating minimum clearance 04:59 Clearance fit: Calculating maximum clearance 05:55 Interference fit 07:26 Interference fit: Calculating maximum interference 08:35 Interference fit: Calculating minimum interference 09:39 Transitional fit 11:03 Transitional fit: Calculating maximum interference 11:50 Transitional fit: Calculating maximum clearance 13:00 Summary 14:25 Determination of the type of fit (fit character, seating type) 16:36 Outlook: fitting systems