On Feb 3, 10:22*pm, Chuck Banshee wrote:
What causes this crazy brown crazing on a varnished steel square?

snip


Can it be fixed?

Not likely. You are storing your tools in a high humidity area. Keep
them dry. Discard the framing square and get a better one made from
aluminum. Even cheap steel squares years ago were heavily copper
plated, and yours is not in that category at all. Moisture and some
raw ferrous material like steel wool could have made the corrosion
marks you see.

Joe