On Fri, Aug 29, 2014 at 5:48 AM, John Griessenwrote: > On 08/29/2014 03:29 AM, Nathan McCorkle wrote: >> >> looking to make a vacuum container wire feed-through, thinking I'll >> drill a hole into an existing aluminum blocking plate > > > How about buying a ready made terminal with plastic around it to silicone > into > a hole in a plate, or hole in a rubber stopper? All the terminals I've seen that mention anything about vacuum or hermetically sealed seem to ring-in in the hundreds of dollars. Also I'd like to try and keep the chemical list down to a minimum, as certain materials like to off-gas for a very long time and that behavior can foul the vacuum and imaging system contained therein. > > Or, the spark lighting electrodes from gas grills (like piezo sparkers come > from)... Hmm, I haven't look at one of those in a while, I've got a box of gas-leaked-out piezo hand-held lighters but they've just got a plastic-insulated wire. Do you have a certain brand? > They look like a glass to metal assembly that might be fairly hermetically > sealed > just by accident... They're 0.25 inch diameter and would fit in a stopper > hole also. > I think there's one of those just down the street at the moment... I'd really like to try the Viton stopper approach, NASA seals walk-in vacuum chambers with doors >15ft wide using Viton o-rings (or used to at least). The rest of the vacuum system uses Viton, which may not be required as this doesn't go through temperature swings or harsh chemical treatment. But I have only really scratched the surface on o-ring vacuum sealing technology, so I'm not sure which rubber compound would be second-best (in terms of how flexible, and also in terms of off-gassing). I know off-gassing can differ between different kinds of RTV silicone, as I've researched the various types of those available for potting electronics. I'll take a look at the grill lighters for sure when I go to the hardware store to look for stoppers. Thanks! _______________________________________________ Hosted by the MEMS and Nanotechnology Exchange, the country's leading provider of MEMS and Nanotechnology design and fabrication services. Visit us at http://www.mems-exchange.org Want to advertise to this community? See http://www.memsnet.org To unsubscribe: http://mail.mems-exchange.org/mailman/listinfo/mems-talk