Does anyone know how Pro calculates the drill and tapped depth of a hole? I am putting a M16 tap into a steel plate. A M16 x 1 gives a tapped depth of 36 and a drill depth of 45, M16 x 1.5 gives a tapped depth of 34.8 and a drill depth of 43.5 and a M16 x 2 gives a tapped depth of 33.6 and a drill depth of 42.
Obviously there is a relation depending on the pitch used. With steel, a tapped depth of 1.5 x the nominal will work. How much more to add for the drill depth?
Hole tables have a DEPTH_RATIO parameter that is specified (default is 1.25). Drill depth is the thread depth multiplied by the depth ratio. Information is found in the help in the Hole section under Using Hole Charts. Drill depth is is overriden if you specify a drill depth value that is larger than the thread depth value.
as close as I can calculate ProE threads a hole 2.02 times the diameter. We normally tap holes 1.5 to 1.75 times the diameter. does any one know how to access this relationship and change it permanetly. It is not located in .hol file. the depth ratio is but not the dia/thread ratio
From what I understand from the hole table the thread depth is related to the hole depth by the DEPTH_RATIO so I don't think the relation you want to use can be added to the hole table (probably a better question for someone at PTC or maybe a change request for the feature). You can however add the relation to the feature in the model.
Forgot to mention you can create UDF that contains the relation. So in your examples you might create two UDF features 1_5D_Hole and 1_75D_Hole.