"Grumpy The Mule" wrote in message
...
Howdy,

In the 70's I worked on a project developing dual use small
boat radar. We had a terrible time with bearing corrosion at
first.

You might want to try wash-out resistant grease intended for
boat trailer wheel hubs.

Good advice.

McMaster-Carr has a good selection of stainless steel bearings
and they have ceramic balls for bearings I believe. I'd want
to play with those a bit first before putting them up on a
tower.

Most folks instantly think of stainless steels for corrosion protection.
However SS is not a particularly corrosion resistant material around salt
water. All commonly available grades of SS are subject to halogen
corrosion, i.e. chlorides in sea water. Before retirement I worked at
Eastman Chemical company in their research laboratories. They frequently
had to resort to rather exotic alloys, such as Hastelloy C-276, for
applications where halogens were involved. These alloys tend to be
extremely expensive and nearly impossible to machine.

I would suggest using lots of a good grease and frequent maintenance if your
rotor is exposed to salt air.

Barry WA4VZQ