Run, don't walk, back there and buy it. Most industrial sewing machines have 1/2" shafts, the Adler has 3/4" shafts. They are an absolute brute of a machine. The machine is so precise it will backstitch directly into the forward stitch needle holes. No other machines are even close to that.
Here's a link to the service manual: CLICK HERE
If you need any more info, do a Google search for Durkopp Adler America.