I thought I was pretty familiar with most fastener types, but this bolt
has me stumped.

I'm holding in my hand a bolt (holds bolt up to monitor so everyone can
see). It is a 5/16-18 carriage head bolt about 1-1/2 inches long. So
far, so normal. But at the tip end (not the head end) there is a 3/16''
hole drilled crossways, perpendicular to the axis of the bolt. This, for
inserting a padlock.

I need a shorter version of this bolt. I can't cut off the drilled end
because the shorter version also needs a cross-drilled end.

I'm all over mcmaster.com (McMaster-Carr for those of us who grew up
with their wonderful yellow paper catalogs) and can't find these things.
Actually, I don't want a carriage head, I just need a standard hex
head.

Anyone here with deep knowledge of the exciting world of bolts?

VANAGON CONTENT: I've removed the rear bumper off Mellow Yellow and am
mounting this swell Spanish-American war vintage Hi-Lift jack Al Knoll
sold me to the bumper mounts. I've drilled holes the proper distance
apart to allow for a couple bolts to protrude rearward and through holes
in the jack's rail. I plan to insert some puny little brass Master
padlocks through the drilled ends of the bolts, once I find some of
those darn things, whatever they are.

Sure, anyone with a bottle opener or toilet plunger could pop off these
dinky padlocks, but I'm just trying to discourage some punk in a
7-Eleven parking lot from making off with a completely unsecured jack.

This has nothing to do with the imminent zombie apocalypse. Honest.
--
Rocky J Squirrel
'84 Westfalia: Mellow Yellow ("The Electrical Banana")
'74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
Bend, OR
KG6RCR