William Sommerwerck wrote:

Ordinary household ammonia on a Q-tip with dissolve it. I usually follow
that with an isopropyl alcohol flush.

Possible problem... Aluminum can be attacked by ammonia and other alkaline
solvents. So, be careful.

Thanks, anything else? Ammonia is restricted here. :-(

Geoff.

--
Geoffrey S. Mendelson N3OWJ/4X1GM
To help restaurants, as part of the "stimulus package", everyone must order
dessert. As part of the socialized health plan, you are forbidden to eat it. :-)