ASME/ANSI B18.17:1968 Type B Standard Thumb Screw is intended for manual adjustment and light-duty fastening. Its head design allows direct finger operation, making it useful where quick assembly, removal, or tool-free access is required.
Thumb screws improve operating efficiency during frequent changeovers, cover removal, position adjustment, and clamping. The Type B form is suitable for U.S. standard equipment or export products, helping keep dimensional systems and spare part management consistent.
This product is used on instrument panels, inspection fixtures, electronic housings, adjustable brackets, and light machinery. Knurled, plated, stainless steel, or other customized configurations can be selected according to appearance, wear resistance, rust protection, and grip requirements.
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Dimensions unit: inch
|
Thread size d |
6# |
8# |
10# |
12# |
1/4 |
5/16 |
3/8 |
7/16 |
1/2 |
|
|
d |
0.138 |
0.164 |
0.19 |
0.216 |
0.25 |
0.3125 |
0.375 |
0.4375 |
0.5 |
|
|
PP |
32 |
32 |
24 & 32 |
24 |
20 |
18 |
16 |
14 |
13 |
|
|
dc |
Max. |
0.45 |
0.51 |
0.58 |
0.71 |
0.83 |
0.96 |
1.09 |
1.4 |
1.54 |
|
Min. |
0.43 |
0.49 |
0.54 |
0.67 |
0.8 |
0.91 |
1.03 |
1.35 |
1.46 |
|
|
k |
Max. |
0.28 |
0.32 |
0.39 |
0.45 |
0.52 |
0.64 |
0.71 |
0.96 |
1.09 |
|
Min. |
0.26 |
0.3 |
0.36 |
0.43 |
0.48 |
0.6 |
0.67 |
0.91 |
1.03 |
|
|
h |
Max. |
0.08 |
0.09 |
0.1 |
0.11 |
0.16 |
0.17 |
0.22 |
0.27 |
0.33 |
|
Min. |
0.06 |
0.07 |
0.08 |
0.09 |
0.14 |
0.14 |
0.18 |
0.24 |
0.29 |
|
|
L |
Max. |
1 |
1 |
2 |
2 |
2.5 |
3 |
3 |
4 |
4 |
|
Min. |
0.25 |
0.38 |
0.38 |
0.38 |
0.5 |
0.5 |
0.75 |
1 |
1 |
|
|
c1 |
Max. |
0.03 |
0.04 |
0.05 |
0.05 |
0.06 |
0.09 |
0.11 |
0.14 |
0.15 |
|
Min. |
0.02 |
0.02 |
0.03 |
0.03 |
0.03 |
0.06 |
0.08 |
0.11 |
0.11 |
|
ABOUT US
Better Fastener is a professional fastener enterprise specializing in the manufacturing of steel washers, stainless steel washers, spring washers and sealingwashers. Founded in 2001 as a washer factory, the company expanded into a comprehensive enterprise integrating washers, nuts, bolts, spring nuts and other fastener products in 2010.
The company positions itself as a provider of comprehensive one-stop services for customers, relying on technological R&D, industrial investment and trade distribution.
With an experienced professional team and a sound sales network, Better Fastener has achieved excellent sales performance in both domestic and foreign markets,and has grown into one of the competitive manufacturers and suppliers in China's industrial fastener industry.
Better Fastener is committed to becoming a trusted fastener supplier for customers with reliable product quality, reasonable prices and on-time delivery
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