[sgreco]

You could try one of two tactics that have worked for my team. If you go to the company and knock on their door, they at least have to hear you out before declining to help; this usually doesn't work, but if you act interested in what they are doing, ask for a tour of their shop, then come back later and ask for help, it you might be able to get their support.

The way that my team gets most of our sponsors is through relationships. Find someone you know, who knows somebody. You may not know someone at any of the metal shops who wants to help you, but if you know someone who wants to help you that know someone at the metal shop, you should have a pretty easy time getting in. This technique is how my team got our metal shop.