How to Clean an Unusual old Chessboard?

[mellow token]

How would I clean and/or restore this chess set? I tried using isopropyl, but the paint comes right off.

The pieces appear to be made of some type of plastic and have felt on the bottom.

[karmic lion]

Start with using a mild detergent and a soft brush, aka warm soapy water and a tooth brush

[paper wigeon]

Also cotton swabs.

[supple zealot]

Dry clean first.

[delicate willow]

Use a plain brush to dust off the loose stuff and mild detergent afterwards

You can use more soap for more sticky dirt and cotton swaps for things like corners and details