Are you not going to need a 'keywords' field with keyword values for each topic?
You want to find the article you once read about designing a router overarm so you type in "router, overarm" (or maybe gooseneck) and find records with those keywords in the keyword field? If you have not thought about how you're going to use the db as opposed to just how to design it, you need to reflect on how to get data as well as how and where to input it.
BTW, I'm also a bit of a woodworker. If you want to discuss/compare, send me a PM.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.