I give my beadblasted EDC knives a polish on the blade usually for the purpose of increasing corrosion resistance. While I was working on doing this to my JYD2 I got the idea to polish only one side, then do a test to see how easily each side will corrode. I gave one side about 20-30 minutes of hand polishing with some 1000 grit sandpaper and left the other side as it came from factory, except where the finish was polished during reprofiling the edge. The "polish" is a quick and unfinished job, but it's enough to do a comparison with.
Polished side - http://i24.tinypic.com/2hy85qc.jpg
Regular side - http://i20.tinypic.com/2d5gep.jpg
Test Materials - Lemon Juice, Vinegar, Mustard & Sweat
The knife was soaked in the test medium then left to sit exposed in the air for roughly 30 minutes each test. In between the blade was checked before cleaning for rust, then rinsed thoroughly in hot water and wiped clean then examined again.
Lemon Juice - After 10 minutes spots appeared on the bead blasted side. At the end of the test the bead blasted side had tiny rust spots, while the polished side was rust free.
Vinegar - No noticable effect
Mustard - Produced larger rust spots than the lemon juice, but in a more concentrated area.
Sweat - No noticable effect
Here is a photo showing the lemon juice rust (Just some very light spotting that doesn't rub off)
So far though the blade held up great. I expected more spotting on the bead blasted side based on my past experiences. When I first got my Kershaw Leek it got rust spots one of the first times it was carried due to me being sweaty. The sweat test in particular I want to repeat, making sure to get more sweat on the blade and possibly keeping it wrapped up in the sweaty rag this time rather than exposed, to better simulate a sweaty pocket. The Leek in question was a 440A model, which is a variable to consider.
I'll repeat the test sometime in the near future, possibly using different corrosive agents and using longer "soak" times. If you have any suggestions for what to use (Keeping in mind this knife will be used around food in the future) let me know.
Polished side - http://i24.tinypic.com/2hy85qc.jpg
Regular side - http://i20.tinypic.com/2d5gep.jpg
Test Materials - Lemon Juice, Vinegar, Mustard & Sweat
The knife was soaked in the test medium then left to sit exposed in the air for roughly 30 minutes each test. In between the blade was checked before cleaning for rust, then rinsed thoroughly in hot water and wiped clean then examined again.
Lemon Juice - After 10 minutes spots appeared on the bead blasted side. At the end of the test the bead blasted side had tiny rust spots, while the polished side was rust free.
Vinegar - No noticable effect
Mustard - Produced larger rust spots than the lemon juice, but in a more concentrated area.
Sweat - No noticable effect
Here is a photo showing the lemon juice rust (Just some very light spotting that doesn't rub off)
So far though the blade held up great. I expected more spotting on the bead blasted side based on my past experiences. When I first got my Kershaw Leek it got rust spots one of the first times it was carried due to me being sweaty. The sweat test in particular I want to repeat, making sure to get more sweat on the blade and possibly keeping it wrapped up in the sweaty rag this time rather than exposed, to better simulate a sweaty pocket. The Leek in question was a 440A model, which is a variable to consider.
I'll repeat the test sometime in the near future, possibly using different corrosive agents and using longer "soak" times. If you have any suggestions for what to use (Keeping in mind this knife will be used around food in the future) let me know.
