General metric threads (basic profile)

• Explanation
• Basic profile (excerpt from JIS B 0205-1:2001)

Explanation

The former JIS B 0205 (1997) (metric coarse thread) and JIS B 0207 (1982) (metric fine thread) have been abolished and replaced by the following four parts based on ISO 68-1 (1998), ISO 1261 (1998), ISO 262 (1998) and ISO 724 (1993).

1. 1.JIS B 0205-1 Part 1: Basic profile
2. 2.JIS B 0205-2 Part 2: General plan
3. 3.JIS B 0205-3 Part 3: Selected sizes for screws, bolts, and nuts
4. 4.JIS B 0205-4 Part 4: Basic dimensions

JIS is being revised in a form based on ISO. JIS contains the following statements.

• The terms “coarse” and “fine” were used to follow conventional practice. However, these terms should not be associated with the concept of quality. It should be understood that the “coarse” pitch is the largest metric pitch actually in circulation.
  (*The above is from JIS B 0205-2 (2001), section 5.2)
• (Outline) Screws meeting the requirements of the standard for general metric threads are indicated by the letter “M” followed by the values of the nominal diameter and pitch (expressed in millimeters) separated by the symbol “X.”
  Example: M8 X 1.25
  For coarse threads listed in JIS B 0205-2, the pitch may be omitted.
  Example: M8
  (*The above is from JIS B 0209-1 (2005), Section 5.2)

Basic profile (excerpt from JIS B 0205-1:2001)

Unit: mm

Pitch P	Ｈ	5/8 H	3/8 H	H/4	H/8
0.2	0.173 205	0.108 253	0.064 952	0.043 301	0.021 651
0.25	0.216 506	0.135 316	0.08 119	0.054 127	0.027 063
0.3	0.259 808	0.16 238	0.097 428	0.064 952	0.032 476
0.35	0.303 109	0.189 443	0.113 666	0.075 777	0.037 889
0.4	0.346 410	0.216 506	0.129 904	0.086 603	0.043 301
0.45	0.389 711	0.243 570	0.146 142	0.097 428	0.048 714
0.5	0.433 013	0.270 633	0.162 380	0.108 253	0.054 127
0.6	0.519 615	0.324 760	0.194 856	0.129 904	0.064 952
0.7	0.606 218	0.378 886	0.227 332	0.151 554	0.075 777
0.75	0.649 519	0.405 949	0.243 570	0.162 380	0.081 190
0.8	0.692 820	0.433 013	0.259 808	0.173 205	0.086 603
1	0.866 025	0.541 266	0.324 760	0.216 506	0.108 253
1.25	1.082 532	0.676 582	0.405 949	0.270 633	0.135 316
1.5	1.299 038	0.811 899	0.487 139	0.324 760	0.162 380
1.75	1.515 544	0.947 215	0.568 329	0.378 886	0.189 443
2	1.732 051	1.082 532	0.649 519	0.433 013	0.216 506
2.5	2.165 063	1.353 165	0.811 899	0.541 266	0.270 633
3	2.598 076	1.623 798	0.974 279	0.649 519	0.324 760

PDF list