The Wordsmith's Forge

He has worked on adaptive equipment in an emergency - that friend of Simon and Tolliver's with the metal splints, and he does make mundane tools. I wouldn't expect him to be sticking his hands on somebody, but could see

a) him seeing something like these (https://nerdist.com/article/prosthetic-limbs-art-alternative-limb-project/) and getting intrigued, or

b) seeing someone with a prosthetic that isn't quite working and thinking "Why can't we do it the easy way?"

He's n introvert, and introverts get hooked on things we find /interesting/.