This is correct. From 35 USC 271: (a) Except as otherwise provided in this title [35 USCS Sects. 1 et seq.], whoever without authority makes, uses or sells any

This is correct. From 35 USC 271: (a) Except as otherwise provided in this title [35 USCS Sects. 1 et seq.], whoever without authority makes, uses or sells any patented invention, within the United States during the term of the patent therefor, infringes the patent. But, as a practical matter, companies don't go after hobbyists printing up something in their basement of course. Both because it's prohibitively expensive versus the expected monetary recovery and it's hard to find someone doing this if they're just doing it in their basement for fun.