Delbert Johnson wrote:

Can anyone shed some light on how to order metric bolts?  It looks like

the

common Grades are 8.8, 9.8 and 10.9.  What Grade should one use for
structural fastening of motor mounts, etc?

If you need bolts that are partially threaded is there a way to specify

the

length of the unthreaded portion?

Should we be using mil-spec bolts and does anyone have a reference to
locating metric bolts using a mil-spec number?

Use metric bolts only if you are forced to. We had a rocket
technical assitance program, and metric is the law of the land.
Fasteners were specified such as  6.35 by 0.0751 (1/4 -28)
as supplied by SPS Jenkenstown PA. Standards and fits for
metric bolts were not world wide, at least at that time,
Vance

 
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