Another restoration question - help me, experts!

[kai]

when I take the blade out of my acid solution, it develops a very fine yellowy - red rust within minutes or seconds. Can I apply my warangan directly over this, or will I get an ugly rust reaction?

I have seen this happening with some blades.

First, you really have to make sure that there are no stubborn rust patches remaining on the blade; the warangan will still work on the clean metal but the longterm stability of the stain as well as the preservation of the blade may be compromised. From the last pic, I believe I do see remaining rust down in the blumbangan area. I'd also double-check all pitted areas and other crevices for "deep" rust: a set of fine needles, 10x (or so) magnification, and good light can do wonders.

Once this old rust is taken care of, I haven't experienced that a hue of powdery instant surface rust is really an issue for the warangan process. I usually move directly from the acid solution (vinegar or pineapple juice) to warangan. However, I prefer to wipe the wet blade with pure lime juice (several times if "dirt" is still coming off) to avoid wasting the precious arsenic and lime mix.

Regards,
Kai