I’m not sure how to use water because the structure is composed of hardboard with fabric glued onto it. Not sure if hardboard is a universal term, here is a picture of what I mean:

A closer zoom of the bottom picture showing construction:

The porous, adsorbent side of the board has had the canvas glued to it. How to rinse that?

(Filesize limits on lemmy prevent posting larger photos.)

hmmm I don’t recall. Would be worth trying. Maybe a shop vac or something really strong would be able to suck off some dirt. If I had access to one. I’ll try the one I have.