Magnetic Discombobulator

Unless it has a chance to explode every time you use it, i don't think this fits the "engineering" theme very well.

Maybe if you're a goblin engineer, I suppose. But the Arclight Spanner has been an engineering staple since vanilla for all engineers. If you think manufacturing those devices won't necessitate the use of at least one wrench you'll probably end up with an paperweight with the all the incendiary power of a lit cigar.

If all you have is ENG, this seems the be, sadly, the 'best' way to 'farm' Expulsom, only thing you can craft that DOSN'T cost Expulsom

As a nice little touch the outer jaws of the weapon (tool?) are animated to open and close. Just make sure you're careful when you sheathe the thing, don't want to do yourself a mischief.