First thing in the shops I have setup in the past are "skirts" along the bottoms edges of every bench, cabinet, machine stand or anywhere sneaky parts can run or hide. This is due to an event 4 decades ago, Was restoring a very rare, early S&W American and the hand flat "disappeared:. Being near impossible to replace, we spent better half of a week looking. When finally found It had made it under an adjacent bench right behind a leg. The skirts and judicious use of those small metal trays with the magnetic bottoms have reduced all the loss of parts (except those that fly up and land on the top of the hanging lights.)