Source for 13 mm hex wrench

[Tom and Carlyn Jervis]

Easiest solution is to get a 13 mm bolt of appropriate length and 
some nuts.  Jam two nuts together (with the flats lined up) at one 
end of the bolt and solder them (or weld) together and you have a 
piece of 13mm hex shaft.  Put your 13mm socket on one end and you are 
ready to go.

Tom Jervis
Los Alamos, NM
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