electrical feedthus
Soldering is not suggested to make wire connections on electrical feedthroughs. For reasons see figure below:
One should use a detachable coupler or a crimp on connector for connecting to feedthrough pins: crimp on connects are something like http://mdcvacuum.com/displayproductcontent.aspx?d=MDC&p=i.9.4.2.1
from US patent 6156978, Peck