On Saturday, September 30, 2017 at 9:27:13 PM UTC+2, wrote:
Another thread mentioned using a credit card, but some time ago, I discovered these:

https://smile.amazon.com/Single-Edge...c+razor+blades

or these:

https://smile.amazon.com/7MO-Scraper...c+razor+blades

They wear out pretty quick, but won't catch the finish.

-Tom

Why not use White Spirit? Works like a charm with some paper towels:

https://en.wikipedia.org/wiki/White_spirit