"Tr 100x6":

"Tr": This refers to the type of thread that needs to be machined. Threads come in various forms and profiles, including V-threads, square threads, buttress threads, and many others. The specific designation "Tr" will indicate the precise thread type and its geometric characteristics, such as the thread angle, shape, and form.

"100": This value signifies the nominal or major diameter of the threaded feature. The diameter can be specified in either metric units (millimeters) or imperial units (inches) based on the drawing's system. In this case, "100" represents the major diameter of the thread.

"6": This number indicates the pitch of the thread, which is the distance between corresponding points on adjacent threads. It can be expressed in threads per inch (TPI) for the imperial system or millimeters per thread (mm/rev) for the metric system. In this context, "6" denotes that there are six threads per unit length, which is typically a reference to threads per inch (TPI) if following the imperial system.

The "Tr 100x6" specification on the drawing tells machinists and manufacturers that they need to create a thread with specific geometric characteristics, major diameter, and thread pitch as outlined in the drawing's associated standards and requirements. To execute this effectively, additional details, such as thread depth, tolerance, and other critical parameters, should be included in the drawing or the accompanying documentation.

In summary, "Tr 100x6" specifies the type of thread, its major diameter, and its pitch, which are crucial details for machinists and manufacturers when creating threaded components. However, to fully understand and implement this specification, additional details such as thread depth, tolerances, and other critical parameters should be provided in the drawing or associated documentation.

"8H":

The notation "8H" refers to the thread tolerance. Thread tolerance defines the acceptable deviation in dimensions and geometry of the thread from the specified values. In this case, "8H" signifies a specific level of tolerance that should be maintained during the machining process.

The letter "H" in "8H" indicates the class of thread fit, which denotes the precision of the tolerance. "H" class typically represents a higher level of precision. Thread tolerance classes range from 1A (loose fit) to 9H (tight fit), with higher numbers indicating stricter tolerance requirements.

The number "8" represents a specific tolerance range within the "H" class. The exact tolerance values for "8H" should be detailed in engineering standards or specifications related to the drawing. These values dictate the allowable variation in thread dimensions and are critical for ensuring that the threaded component will function correctly and fit properly with other threaded parts.

"8E"：

The notation "8E" likely refers to another aspect of tolerance or fit, which could be related to a different dimension or feature on the CNC drawing. Unfortunately, the meaning of "8E" can vary depending on the specific context of the drawing or the engineering standard being used.

In a similar fashion to "8H," the "8" would typically represent a specific tolerance range, while the letter "E" could indicate the class or type of tolerance fit. To fully understand the significance of "8E," it is essential to refer to the drawing's associated documentation and relevant engineering standards to determine the specific dimension or feature to which this tolerance applies.

In summary, "8H" and "8E" denote specific tolerance levels for different features on the CNC drawing. They are crucial for ensuring that the machined components meet the required specifications and quality standards in terms of thread dimensions and other associated dimensions or features. The exact values for these tolerances should be outlined in the drawing's documentation and relevant engineering standards.