I can tell you from firsthand experience that accidentally stripping a bolt by rounding it off or cross threading it can be a massive pain when you’re standing in your garage here on earth. I can only imagine that a stripped bolt on important device orbiting the Earth aboard the ISS would be even more frustrating and difficult to deal with. Astronauts recently attempted to attach a new device to route power on the ISS to the outside of the station.
The problem for the astronauts on the space walk was that they were unable to tighten one of the bolts. The original space walk team was tasked with attaching a device to help route power generated by the solar panels aboard the ISS to the space station’s internal systems. NASA says that the station has three functional units and that there is no danger of blackouts aboard the space station.
NASA stated that flight controllers have been able to route power to critical station systems even with the new module uninstalled. NASA decided to have the astronauts quit fussing about with the difficult bolt while they reconsidered options. NASA ultimately decided that the most likely cause for the difficult bolt was some sort of slight misalignment in the positioning of the spare unit for installation before bolting, leading to possible damage of the threads.
In other words, one of the astronauts cross-threaded the bolt. Considering the number of times I’ve done that in the garage while fiddling with a car, I can understand. The spare unit the astronauts were trying to install has a bolt that needs to be tightened with at least 15 turns be considered secure. However, the stripped bolt continues to stick on the ninth turn. Astronauts will take another spacewalk tomorrow to attempt to finish the installation. I suggest wire ties and duct tape if the bolt continues to be difficult.
[via The Register]