Unusual Etch on a Moro Blade

[Spunjer]

Originally Posted by DaveS

Spiral: I've had this happen before also after using vinegar to neutralize the
Phosphoric acid that i usually use to etch blades. It seems strange
to me that one acid can be used to neutralize another, but i guess
for some reason it works. Try also heating blades on both sides with
a torch (very carefully). Then apply acid. It seems to emphasize
the high-carbon areas of a blade with some really good results. If
the blade turns out too dark simply repolish, and try again....Dave

i would normally use a heat gun (use to strip paint) to warm the blade, not hot to touch, before applying my first layer of warm vinegar. you're right, in that it does emphasize certain areas of the blade when etching. never tried phosphoric acid, dave. pretty much stayed with vinegar.

mross: yes it does. but what i don't understand is why is the opposite side has a different pattern? was the core sandwiched together?