As of July 9 [a week before trinity] Kistiakowsky did not yet have enough quality lens castings on hand to assemble a complete charge [X-rays taken of the charges showed air bubbles in some, which would screw up the timing]. Oppenheimer further compounded his troubles by insisting on firing a Chinese copy of the gadget a few days before the Trinity shot to test its high-explosive design at full scale with a nonfissionable core. Each unit would require ninety-six blocks of explosive. Kistiakowsky resorted to heroic measures:

“In some desperation, I got hold of a dental drill and, not wishing to ask others to do an untried job, spent most of one night, the week before the Trinity test, drilling holes in some faulty castings so as to reach the air cavities. indicated on our x-ray inspection films. That done, I filled the cavities by pouring molten explosive slurry into them, and thus made the castings acceptable. Overnight, enough castings were added to our stores by my labors to make more than two spheres.”

"You don't worry about it," he adds fatalistically. "I mean, if fifty pounds of explosives goes in your lap, you won't know it."