With very few exceptions, all of our mentors are family members of (sometimes former) team members, or graduated team members. The one exception who's been there a while was pulled in by Gixxy at church - that's what he gets for letting the whole parish know that he earned a PhD in ME.
The biggest obstacle for many prospective members is convincing them that yes, the do have exactly the knowledge and skills we need. I don't believe that any of our mentors ever worked with robots before FRC. Our four most active technical mentors for the last two years are an oceanographer, an electrical/pneumatics guy (though anything smaller than 8 gauge is a control wire to him professionally), a commercial A/C repairman. and a computer programmer. The head coach is a biology teacher. The best response to "I don't know anything about building a robot" is something like "You know a lot about <fill in the blank>, so whether you realize it or not, you definitely know
something about building a robot". In one recent case it was more like "You manage a business - and running a team that builds a robot requires the same skills." The bottom line is to sell prospective mentors on three key points:
- You do have skills that the team needs; you can contribute.
- You're helping shape the next generation of leaders in technology and business, and will learn a good bit yourself.
- While FIRST uses this mainly for students, it's also true for mentors: FRC is the hardest fun you'll ever have!
Another place to look for mentors is in the same sorts of places you look for local parts and sponsors - whatever tech, electrical, hardware, software shops are in your area. Is there a local car club, computer users group, or radio control club?