How do I remove spilt superglue from a plastic surface?
Tricky, it really depends on the plastic it’s glued to, and the exact composition of the superglue. You can get superglue debonder, which you may have to apply several times. If it’s a hard plastic, you could try soaking some cotton wool in white spirit. Put it onto the superglue, cover with plastic – a freezer bag or clingfilm, and leave overnight. The white spirit attacks the glue (and also some softer plastics) and in the morning you should be able to lift it off. I discovered this by accident when white spirit dissolved the glue on a perspex tank I made and the whole thing fell to bits. As an ex professional modelmaker, my personal approach would be to carefully slice it off with a scalpel, but you’ll need a steady hand and some skill to make a neat job of this.