1922 or 23 Singer 71-30 industrial buttonholer

I recently acquired this early 1920's Singer 71-30 industrial buttonholer as a "package deal" with a 1949 Singer bar tacker from a family that literally rescued these two machines from the trash. I'm just learning about this machine as I go along, and have started the process of cleaning it, as it had obviously sat a while. I understand that they're still used locally in the Los Angeles, CA area in small industrial shops. This thing is unbelievably heavy. It came with a fairly standard-looking industrial table with that old green laminate, and two separate pedals to lift the presser foot frame and to activate a cycle of sewing. The frame that it sits on with the flip-down pulley cover is easily over 40 lbs alone; then add the machine and you'll feel it in the back the next day as the machine exceeds 70 lbs. It is an amazing example of turn-of-the-century engineering, and even if it sat on a (really sturdy) shelf as industrial art, it is a head-turner. I can't wait to fire it up. The few videos available on YouTube are amazing.