On Friday, October 31, 2003, at 12:43 PM, John T. M. Lyles wrote: > Oil works too. We use it at work to standoff 90 KV DC for big > klystrons, while affording some cooling. We use Shell Diala. Biggest > concern is leaks, what a mess it can make. > There are some 3M heat transfer fluids which are nice but expensive. Amen, FC75 used to cost Raytheon c. $600 a gallon.