Autococker07

Whew, thanks for the talk down yall..... so evidence of prior corrosion may be left by a previous polisher? I was just not anticipating finding any corrosion at all, and overall the blade is much better than this one spot. I deal with raw carbon steel a fair amount, and have never seen super aggressive rust/pitting, but have heard/read horror stories of things aggravating rust (glue on sword rack felt, etc). As I stated above, I use carbon steel in the kitchen, but wipe down with oil each use and have never had an issue... On this sword I am using Wilson Ultima Lube II universal gun lube...... I don't know if it has rust prohibiters like the express stuff, but I use it on all my firearms, and it works great. That said, I am not set on one particular oil. This stuff is slightly thicker than typical oil, and I like that I can put it on and see the coverage, (my eyes aren't that great anymore) so liberally just means that I can see the oil, not that it is dripping off or anything..... about 5 thousandths. I like the pictures idea.... that may be today's project!

So I went off half cocked and bought this sword last week. It arrived to the house on the 17th. I immediately looked it over quickly, with powdered nitrile gloves on, then oiled it liberally, and put it away. I have had it out of its shirasaya about 3-4 times to admire quickly, each time re-oiling it (using unscented Kleenex) before putting it away in shirasaya and sword bag. Today I finally had some time to relax and take a loupe to it, under bright 5k lighting..... and I notice this..... (Hard to see in tiny picture, but corrosion on the Ha) I am devastated, how big of a problem is this? I have used carbon steel kitchen knives for years that have never rusted, and certainly not in a weeks time. I feel terrible like I have failed this 340 year old blade, and would love any suggestion both on repair or general upkeep to at least contain the corrosion if repair is not possible.