The Untinker is also located on the wrong side of the tracks.

he tell you he had his screwdriver taken near Degrassi Knoll. So adventure there until you get it, and then return it to him.

if you accend under the muscle sign that all you have to do is go in side to the innabox guy there and he will give it to you for free, and take it to the untinker

The Untinker can uncombine any items that you have combined with meat paste.
He cannot: unsmith weapons
uncook food
unmix cocktails