Cmon, Scotty often saved the day using band-aids and a wrench.
One of my favorite scnes with him is in That Which Survives when he has to crawl into that chamber to fix something or the ship will be blown to bits.
The dialog between Spock and Scotty is priceless;
Lt. Cmdr Scotty : [working in the service crawlway] I'm so close to the flow now that it feels like ants crawling all over my body.
Mr. Spock: Mr Scott, I suggest you refrain from any further subjective descriptions. You now have 10 minutes and 19 seconds in which to perform your task.
Mr. Spock: Mr. Scott, you have accomplished your task.
Scotty: You might at least say thank you.
Mr. Spock: For what purpose, Mr. Scott? What is it in you humans that requires an overwhelming display of emotion in a situation such as this?
'Scotty' : [muttering] Never mind.
Mr. Spock: Two men pursue the only reasonable course of action, and yet you feel that something else is necessary.