Are the screws of M5, M6, M7, and M8 available in fine-thread and coarse-thread versions?
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Are the screws of M5, M6, M7, and M8 available in fine-thread and coarse-thread versions? Are there still only fine teeth and no coarse teeth? How is a fine thread indicated? Is it M7*0?
1. Screws of sizes M5, M6, M7, and M8 come in both fine-threaded and coarse-threaded versions. 2. According to the standards, even for M1, there are different thread types: the coarse thread has a pitch of 0.25, while the fine thread has a pitch of 0.2. 3. M5 belongs to the first series; its coarse thread has a pitch of 0.8, and its fine thread has a pitch of 0.5. 4. M6 also belongs to the first series; its coarse thread has a pitch of 1.0, and its fine thread has a pitch of 0.75. 5. M7 belongs to the second series; its coarse thread has a pitch of 1.0, and its fine thread has a pitch of 0.75. 6. M8 belongs to the first series; its coarse thread has a pitch of 1.25, and its fine thread has a pitch of 0.75
But I measured and found that the pitch of an M5 screw is clearly 1 mm
1. There are various standards for threads, and no efforts have been made to collect or compare the differences between these standards. 2. The data mentioned above is taken from GB/T 196-2003 on basic dimensions of ordinary threads; it has been modified to conform to ISO724:1993 regarding basic dimensions of metric threads for general purposes. 3. Since the poster confirmed that it is an M5 thread with a pitch of 1 mm, there are other factors to consider