I had some concrete clean up to do after a build to remove dye and Cory's Goop and started with diluted muriatic acid and water. The dye came off easy enough but the goop didn't budge. I then tried staight acid and still the goop wouldn't give in. I can remove it with a scraper of torch but was amazed.

We also did some stab test on the nylon and that stuff is tougher than I thought