Foam Sprayer is an IC2 tool that coats blocks and HV cables with Construction Foam, hardening into Reinforced Stone.
Guide
At a crafting table, combine iron, a compressor, and an empty cell to produce a Foam Sprayer.
Craft Construction Foam Pellets (CF Pellets) from Construction Foam in your inventory; you will need a full stack for large projects.
Combine the Foam Sprayer with CF Pellets in a crafting grid to fill its internal ammo store.
Hold the sprayer and right-click an HV cable or block to apply a soft Construction Foam layer.
After about one in-game day the foam dries into Construction Foam Wall, a Reinforced Stone variant safe for HV wiring and creeper-proof.
Mine hardened foam with a pickaxe; never touch a bare HV cable carrying 2048 EU/t.
Craft Construction Foam first using IC2 recipes, then convert it into CF Pellets that the Foam Sprayer can load.
After about one in-game day the soft foam dries into Construction Foam Wall, a Reinforced Stone variant with strong blast resistance.
HV cables in IC2 carry up to 2048 EU/t and electrocute any player or mob touching them; a hardened foam coat makes the cable safe to walk past.
Mine the hardened Construction Foam Wall with a pickaxe, like any Reinforced Stone block.
In some IC2 versions you can color the foam during application, which is useful for tagging cables and decorating bases.