[Gdeaver]

Ferric chloride does stain. There is still a spot on our counter top from my circuit board learning experience 5 years ago. My wife still reminds me of my transgression. Don't etch your boards in the kitchen. Oh, and while I'm on the topic of the kitchen and robot projects, don't bake your composite layups in the family oven. I'm still reminded of that. Though our head mentor did get away with heat soaking our polycarbonate battery box in his families oven this year. He seemed to get away with it.