Reply To: Engineering Prof releases draft report on 9/11 collapse of WTC Bldg 7 in NYC Latest News › Forums › Discussion Forum › Engineering Prof releases draft report on 9/11 collapse of WTC Bldg 7 in NYC › Reply To: Engineering Prof releases draft report on 9/11 collapse of WTC Bldg 7 in NYC September 6, 2019 at 07:18 #46921 Gerry The boring holes bit doesn’t apply so much to steel frames. 45 degree cut charges to make the core step off itself doesnt need holes drilling.