Hi Jeff,
I've been using (probably) the cheapest solution out there (apart from my stencil).
I had a stencil made by Ernie Grospitch (sp?). I use a simple 9V battery (Duracell) with two crocodile clips attached to it. The red (+) terminal gets clipped to the blade, and the black (-) terminal gets clipped to a small piece of flat steel which is wrapped in a small cotton pad. I make a simple solution of about a teaspoon of salt dissolved in a 1/2 cup of water. I use this to dampen the cotton pad with. Tape the stencil to the blade, and press down firmly for about 3 minutes (hardened steel), or 1 1/2 minutes (annealed steel).
Simple as that - works like a charm!