A month-old thread "[OT] Special bolts" in sci.electronics.design,
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(or "O.T. Special bolts" in comp.cad.solidworks) may be of interest to anyone with special fastening needs (ie, fixing or making screwups). See
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for diagrams.
The captions are in German, as appropriate for DIN standards. Not all of the translations in the thread are to be relied on, particularly those at the end of Genome's last post in the thread,
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Note, Schraube=screw, sonder ~ special, Loch=hole, doppelt gebohrte= double bored, Montageschraube=mounting screw. DIN 895 says Räumschraube Zum Säubern von Bohrungen [space screw to clean the bore] but I don't see much difference between it and DIN 909, Sonderschraube mit Passfeder als Ausdrehsicherung [specialscrew with passthread?? like withdrawalsecurity?? ].
-jiw