The Versa-Blade and a cycles question

Here is a sword I’ve been working on. It has 5 different blade combinations, 3 different tsuka (handles), and 2 different tsuba (guards).

I’m happy with the overall design and the textures are OK, but I’m having some trouble with bump mapping. Specifically, a bit of text for the blade. I can get a positive bump to show, but I’d like a negative bump (like the text was etched or carved into the blade). I can’t seem to get it to work. For the positive bump maps, I’ve got white areas for the high parts, and when I try to use black for a negative bump, I get crap. And yes, I know the tsuka is non-traditional – the whole sword is actually.

Here is my node setup for the bump maps. Any help would be appreciated.

Instead of a “RGB to BW” node which isn’t really necessary, use a “Color Invert” node.

And keep the Math node because you will want to reduce the depth of the carving in multiplying by a very small value.

That seems to have worked, but I had to make the image black with dark gray text. I guess cycles is picky when it comes to bump maps.