(Related: How is the unwanted cold welding prevented in space?)

I've often seen talk about fairly simple mechanical devices (hand tools, simple handheld power tools, firearms, etc) being unlikely to work if not specially modified for use in the vacuum of space because of the evaporation of lubricants and the tendency for metal to cold-weld. The modifications tend to focus on high-tech treatments such as dry lubricants, Teflon bearings, and special solid lubricant coatings. This is especially pronounced in writings for a popular audience, such as articles about NASA's handheld EVA power tools.

However, modern industry provides plenty of vacuum-grade oils and grease bases such as silicones (such as the wretched and ubiquitous turquoise tube Dow grease), perfluoropolyethers (such as Fomblin and Krytox), or low-vapor-pressure hydrocarbons (such as Apiezon grease). These have vapor pressures at 25 deg C of well under 10E-6 torr, and often maintain low vapor pressures of under a few millitorr at high temperatures. For lubrication purposes they may be made into greases containing colloidal PTFE, moly, graphite, or boron nitride.

Could simple mechanical devices designed for commercial-grade use on Earth be "vacuumized" by re-lubricating them with such greases and oils, and work reliably in space for some hours or days? Clearly this isn't suitable for long-duration unmanned satellites or safety-critical anything, but is it enough to mitigate the basic issue and make equipment usable without redesign?



Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.