Tell us about yourself!
I guess I missed the fact that you're shrinking the entire covering; I thought from the text that you were just activating the adhesive, so I assumed that over the ribs was what mattered.Having said that, when covering a full size aircraft with dacron, an iron is *always* used to shrink the fabric, to maintain proper temperature control on the fabric. (Required to avoid under/over-tensioning.) On a roughly 5' x 15' wing, the heat shrinking with an iron takes an hour or two. Probably the least time consuming part of the covering process. (Just assisted in recovering the wings on a Kolb Twinstar.)