/diy/ - Do It Yourself

Any cheap organic alternatives to walnut shell dust? for sandblasting. I need to clean a cooking plate like this but I can't find any store that sells 5kg sacks online, there is either 20kg that costs almost as much as a new plate or 1kg overpriced sacks, it's mostly an issue of shipping costs since I'm in EU so this is why I'm looking for a cheaper alternative.
I thought of trying sea sand since I can get that for free but you just don't know what's inside it, I'm sure there is plastic and other kinds of polymers or silicon.
I looked up glass beads sand but it's not being sold in EU and although it's a bit cheaper than walnut shell sand, it's still expensive due to the shipping costs. I found glass shards sand but I don't think it's a good idea since I'm going to cook over this plate later and glass can get very thin and hard to remove completely.
I'm using a normal gravity blaster by the way.