MB
Since you said you wanted to do something on the side, that might be the best way to do something like that. I know a guy that used to run a small shop in his basement for many years. He was open from 6-10, m-th That was it. He did alot of business, but didn't let it ruin his weekends.
I used to (for years) build arrows, set up & tune bows, etc... for a bunch of guys around where I live, and all my buddies. It wasn't alot of extra cash, but it paid for all of my hunting expenses for probably7 years.
I had actually thought about doing it full time years ago, and decided against it for the reasons many have stated... mainly not muchtime to fish or hunt. But hey, if you feel like you need to do it, go for it. Only you can decide if its what you want or not.

I know several guys that have now, or have had shops. Most work alot of hours, but that is most likely going to come with any business if you want to truly succeed. Good luck whatever you decide.