I've always wanted to build myself a custom lugged steel bike frame. The idea is to build a classic steel road frame with lively 74 degree angles like the steel racers I rode as a kid.

I found a Columbus SL Tubeset and matching lugs from Nova, and once received, cut each tube to length (size 58.5 c-c) using a tube angle jig that worked with a 1/2" drill motor and a hole saw arbor that a buddy loaned me.

I built a frame jig primarily from 80/20 extrusion, with some machined and threaded cones to center the bottom bracket, head tube, and seat tube, as well as an extension using an old rear axle for centering and aligning the rear dropouts.

I'm getting close to being ready to assemble the frame with flux in the joints and clamp it into the jig to begin brazing, but I have a question about the joints at the seattube to toptube, toptube to headtube, and headtube to downtube. I have read that since the toptube is captured at both ends, failing to drill a hole in at least one of the tubes (head and seat) behind the lug will cause air to be trapped which will heat and try to expand without the hole to let the hot air escape.

My question (finally!) is would it be ok to drill out each of the three joints to lighten the frame, which I'd like to do as this is a dream build for me, or would this affect the structural integrity or stiffness of the build?