A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Ed Popko
Date: 2017 Oct 14, 06:05 -0700
This particular square tubing was the smallest I could find. The inside opening It is a bit larger than the Astra IIIB stud but still snug. The dimensions are:
Outside Face .125" 3.175mm
Wall Thickness .015" 0.381mm
Inside dimension .095" 2.413mm
Again, I found this square tubing in a hobby shop that had mostly trains and railroad scenery items such as trees, lighting fixtures, people and ... brass structural elements like tubing, beams and plates for building bridges, towers or simulating cargo on railroad cars.