I've recently purchased a Damascus knife and am patiently awaiting it's arrival in the mail. I have been researching the potential care and maintenance habits for this craftsman blade, hoping to keep it in pristine condition.
I'm wondering what measure(s) could be taken to prevent a Damascus knife from rusting. I will be crafting the handle from my own scales and pins upon receiving the item, so any manipulation done to the steel can be preformed upon the blade in its entirety. The alloys used are a mix of 1095 and 15n20 steels respectively.
One of the potential means that I've entertained the thought of is bluing, AKA a black oxide finish. Bluing is a method commonly used on gun metal in which various gun parts are submerged in caustic hot salt baths for a period of time in-order to attain the coat. This isn't the only method to obtain the oxide layer, it's but one of many. Some sources have stated that bluing provides rust resistance while others are skeptical since most oxide layers as a result of the process are merely 2.5 micrometres (0.0001 inches) in thickness.
The method I'm most interested in potentially trying is cold bluing. Cold bluing can be achieved either by coating the high-carbon steel in mustard, painting it in a commercially sold "perma-blue formula", or submerging it in an acidic at-home substance such as vinegar or lemon juice (boiling vinegar to enhance the effect).
Here is my question Ultimately TL:DR Can a true rust resistant layer be obtained via cold-bluing methods on high-carbon Damascus steel (1095 & 15n20)? Will the acidic substance such as vinegar or "perma-blue formula" simply eat through the steel with time (while I'm letting the bluing process take place before I've neutralized the blade with something such as baking soda), or will it develop a thicker layer of patina oxide layer? Some sources say the bluing layer is rust, therefore rust can't develop on top of rust. Others say bluing is purely cosmetic and can not prevent rust.