Andy came to paper engineering as a tinkerer and repairer of antique record players, radios, automobiles and other mechanical and electrical devices. He is based in Santa Fe, New Mexico and is now a master clockmaker.

Paul's collaboration with Andy was trans-continental-- a monumental effort, involving many hundreds of hours of telephone calls, masses of e-mails, and a considerable amount of overnight shipping. Paul contributed to the book's mechanics as well. Andy even suggested a shared credit for paper engineering, which Paul declined. (In fact, the same thing had happened with The Wheels on the Bus, which was developed originally from Paul's working model.) It was close to a full year of collaborating before Knick-Knack Paddywhack! was ready to send to the printer. And in this year of virtually daily contact (before the days of video calling) the two had not met once face-to-face.

However, the work was not done. There was still a need to oversee the book's printing and assembly. It was in the city of Shenzhen, China, where the two met for the first time.