Originally Posted by
Andrew R Stewart
I'll add to Eric's good reply that a mock (or real...) lug/sleeve can be made with two tubes very easily. The outer tube (the one which is the "lug") needs to be 1/8" larger in diameter then the inner tube (the "frame tube") and have a .058" wall. This results in a near perfect sliding fit suitible for both brass and Silver practice. So a "frame tube" of 1" diameter would need a "lug" tube of 1 1/8" x .058" wall. Here's a link to Aircraft Spruce, a source for said stuff. Andy.
http://www.aircraftspruce.com/catalo...tubing_un1.php
I'll add to Andy's note;
If one is going to make lugs to fit and are using a mill, a Joint Jigger, or similar machinery to mitre the frame tubes... Then it makes sense to take advantage of the machine settings. Thus as soon as one end of a frame tube is mitred, just pop in the 1/8" larger tube and cut its mitre using the same settings as its respective frame tube end.
Hope that helps someone save some setup time and maybe some filing time also.
/K