As a kid, we actually did "junior versions" with shorter twine, but the principle is quite sound. You can probably find the "barn door bass" with a quick Google. Only a few of the sources I've seen though mention the possibility of really long strings and "longitudinal mode excitation."

A cousin claimed that a "friend" tried to do the full scale one, but he messed up and used baling wire instead of twine. When he couldn't get the tension up to snuff he hooked onto a tractor (a small one) but the instrument failed 'cause the barn door came off the hinges. (I suspect it was an old barn, with pretty soft wood around the hinge bolts. My cousin would never have made up somethin' like that.)

As a pre-teen, I used to annoy my mom by "stroking" the steel clotheslines on my way out the back door. They got longitudinal mode squeals pretty easily once you learned how. About 45 feet long, they'd hit E string fiddle notes. She finally had dad loosen the wires so they weren't quite so responsive.

It's pretty easy to get the "longitudinal mode" vibration on a guitar just by sliding your fingers lengthwise along the string. It would seem that only a fiddle or hurdy gurdy would be likely to get the torsional mode. It probably is necessary to have the strings at least slightly "out of round" as well as twisted, and to use a bow or other "rubbing device" to get much windup in the right direction on the strings.

John