Screws Fastenings Index
Relevant Tables
Thread dimensions for ISO "medium" class threads 1,6mm to 300mm
Equations & Tables for Screw Thread Tolerance calculations
Suppliers sites with Screw sizes/Specs
- Fuller metric.. Extensive range on DIN/ISO standard screws with dimensions
- PTS-UK.. Sizes of various type of Screws
Sites Providing Information On Bolt/Screw Design
- Bolt Science..A site dedicated to the Science & Technology of bolted joints
- Threaded Fasteners..A Section of the Site DESIGN AND ANALYSIS OF MACHINE ELEMENTS.
- Bolted Joints..An informative paper published on the Web
- Metric Bolt Strength..Bolt Sizes Strengths- American bias
- Croberts Com..Very useful section on the consequence of Bolt Failure
- Fastener Design Manual...NASA GRC RP-1228 (9.6 Mbyte pdf file). Design info on bolt + rivet joints
- Bolt Council Publications...Guide to Design Criteria for Bolted and Riveted Joints.(6.7 Mbyte pdf file). Excellent ....
- The yielding of fasteners during tightening...An article with surprising conclusions
- Keeping It All Together ...Practical notes on bolted joints from an enthuiast
- International Thread Standards .. A comprehensive set of thread tables including BSP
- Engineering Fundamentals of Threaded Fastener Design and Analysis ..Very detailed and informative downloadable document
Note: on tapping holes:
I normally specify a tapped hole depth of 1.5 dia for a fully threaded hole in a blind tapped hole (steel male and female).
The depth of threaded hole if a plug tap is not used i.e for automatic one stage tapping would be deeper.
According to BS1936 the tapping drill should be have a depth greater than the tapped depth (clearance depth) as follows
Less than M6 = 0.25 x full thread depth...
M6 TO M12 = 0.2 x full thread depth...
Greater than M12 = 0.15 x full thread depth.