The printing technique we use at Digital Alloys requires that we maintain an inert atmosphere inside our printers to inhibit oxidation of the metals we print with. We use argon gas pumped into a large hermetically sealed glove box. Maintaining this environment is not easy given that we must pass hundreds of wires into the sealed chamber. Early versions of the printer had difficulty maintaining the environment because outside air made its way into the box traveling between the cable insulation and the wires within. This was solved by employing hermetically sealed pass-through connectors. The price for one such connector for a USB connection is $650. When a purchase request came to me for two of these, I could not believe the price. I denied the request and returned home this evening to build one myself. I cut the end off a USB extender cable, peeled away all the molded plastic and resoldered the connection leaving about a half-inch of bare, tinned wire. I then potted this end of the connector inside an empty pass-through housing with an inch of epoxy. The cross-section of the hermetic boundary is four tinned 24 gauge wires. I can guarantee this will work and the cost for the USB components and epoxy was under $8.