this is copied from the framebuilder's list, originally written by Tom Teesdale, http://www.tetcycles.com/
I will let someone else do the lug and fillet....for tig...this is a main
triangle that is tacked
(BTW--for any type of joint construction--finish the joints in this order,
BB, DT/HT, TT/HT, ST/TT. theory is if you are going to build stresses
frame from welding/brazing, have them accumalate at the least stressed
start at the top of the joint between the seat tube and down tube. weld to
the bb then continue quarter way around dt and quarter way around seat tube.
Turn frame over and repeat with the other side.
go back to the first side and weld the back side of the seat tube all the way
to the other side..completes the seat tube.
start at the bottom of the dt on the bb and weld one side up
start at the same point on the bottom of the shell and complete the other
side of the dt. BB is now done
I do the tt and dt head tube joints at the same time.
weld 12:00 to 3:00 on the TT and then the DT
turn frame over and weld 6 to 9 on the dt then tt
turnover and weld 6 to 3 on dt then tt
turn and do 12 to 9 ,dt then tt HT is now done
12 to 9
6 to 3
6 to 9
12 to 3
I am left handed so you right handers might do a different order
12 to 6 on the outside of each
12 to 6 on the inside of each
I always have an axle in the drops spaced just a bit wide
Tom @ TET