No Hex in Evergreens catalog- https://www.evergreenscalemodels.com/Shapes.htm

Plastruct got it- http://www.plastruct.com

Honeycut's original posted method is still a good one, LHS or not. I still use it, after ten plus years, for a few reasons. (When I started hex rod wasn't even available-it's a relatively new product)
One, the largest Plastruct hex rod my LHS has is 1.5mm. It's not large enough for several applications, the main one being replacing track tension nuts on the old Tamiya Centurions, which are poorly cast. I'm sure other kits have these as well.
Two, it eliminates the problem of not getting square cuts.
Three, it's a HUGE time saver if you need uniform nut/bolt detail. This would take a long time with hex and rod, especially when trying to square up both. Easy method: Superglue a piece of rod to the end of the Allen wrench before making impressions in clay. The nut/bolt detail comes out perfectly every time. (The superglue burns off the wrench afterwards)




When I do have to use Plastruct hex rod,which I love,by the way, I try to cut as square as possible, but even everything out afterwards by using a piece of wet/dry sandpaper spray mounted to a piece of plexiglass. Note the square, and even, bolt tops.

beautifully done!