On Jun 27, 8:39 pm, Brian Whatcott wrote:
On Tue, 26 Jun 2007 01:29:07 -0700, Keith
I used pure mineral oil from the drug store in my aircraft compas. It
was somewhat thicker than what came out, but it really improves the
damping where I no longer had any question about which way I was
pointing. To put it in I took a very small drill and drilled a hole
in the case and used a needle (also available at the drug store) to
inject it. I then sealed the hole with epoxy. Make sure the outside
of the housing is clean of oil (use alcohol) so the epoxy will stick.


wrote:

Use half mineral oil and half deodorized kerosene.

The deodorized kerosene (Lamp oil) is cut with mineral oil to increase
viscosity and improve damping.
In the past, the "whisky" compass used alcohol and distilled water
for a slightly denser formulation.

These fluids get thick at low temperatures. For the Arctic, a
synthetic oil might be a better bet - a flatter viscosity curve with
temperature. The extras that go in can be defoamers/detergents.

Brian Whatcott Altus OK