Thread: Black Spot on Edge

You mean something like this ?

Yes, what I have on my blade looks very similar to your pic, onimaru55. My spot is on the very edge, though, and it's hard to tell what is black from corrosion and what is blank space. I wish I could post my own pic.

As you can imagine, those spots would eventually hit the edge with subsequent honing. Then they would chip out into a semicircular shape.
Having one or 2 micropits on an edge is usually no big deal & they can't be felt in the shave unless maybe you have uber soft skin.
Bottom line is, this is rust & as already suggested, oiling is a good maintenance plan but if it's right on the edge wouldn't hurt to hone it out & possibly even clean up the bevel of other potential corrosion.

Almost looks like the swiss cheese edge i posted a few weeks back. Holes all the way thru the bevel. I managed to hone them out and had a great shave afterwards. So if your a honer, hone it out if its on the edge. Get rid of it. It can grow with time.

Any time steel has contact with moisture and oxygen, there is always the possibility of corrosion. The most common oxide of iron is Ferric Oxide Fe2O3. It is the compound we call red iron or rust, a compound sometimes called magnetite.

There is also a Ferrous Oxide with the forumla FeO. Although sometimes called rust, that is not accurate. FeO is black. There are other oxides of iron, but they are less common.

Some steel alloys contain other metals such as Chromium, Manganese, Vanadium, etc. Some of these can also form oxidation products as well.

The best defence against oxidation/corrosion of the blade is to eliminate contact with acids, salts, water, and oxygen. While that is unavoidable during the shaving process, you can minimize exposure afterward by through cleaning, drying, and oiling of the blade.

After every shave, I rinse my blade, dry it on a clean,dry towel, and then coat it with a mixture of a non-toxic oil and 90% isopropyl alcohol. Unlike 70% isopropyl alcohol, 90% alcohol will evaporate and take with it any residual moisture on the blade. This leaves behind a thin film of oil to protect the blade from moisture and oxygen. Some non-toxic oils are mineral oil, Ballistol, and camelia oil.

My oil of choice is Ultra Lube 4-X lubricant and penetrant which is a non-toxic, synthetic oil. I also use it to protect and lubricate tools, fishing reels, guns, etc.

Just a thought, are the scales nitrocellulose? If they're 'going off' newfound rust/pitting like you describe would be expected....

Cheers, Steve

Originally Posted by Steve56

Just a thought, are the scales nitrocellulose? If they're 'going off' newfound rust/pitting like you describe would be expected....

Cheers, Steve

Steve, if you look at the first pic at this post you'll see what the first stages of the effects of celluloid scales 'Gassing' looks like (I've seen it first hand). The heavy devastation takes awhile and it's typically not in spots/however some of the tortoise shell look a like can have that but there again they are much larger. I believe that the consensus of there being moisture left did cause the small spots of corrosion.

http://straightrazorpalace.com/works...uloid-rot.html

Yes I’ve seen that fine, frosty pitting from bad scales before, but also on a Geneva I have, some black pitting spots showed up on the freshly honed bevel. Just a thought.

Cheers, Steve

Nothing wrong with thinking

Yeah, I really think the corrosion is from moisture. The scales on the razor in question are horn.