- Joined
- Dec 16, 2007
- Messages
- 152
Now a days, we see knives having coats of many colors especially in PVC. Back in the old days, all knives had no coating. Mostly good old fashioned polished or satin finished. Then military people started asking for a non reflecting blade. This promoted bead blasting or sand blasting. Problem with that one was that blasting promotes iron oxidation - basically rusting even on blades like CPM S30V. I noticed this just after a month in South East Asia on Trident Oblander 02 and Lone Wolf T2 ranger. Both knife showed reddish brown spots. Now, this gets worse where blade is not smooth. To my understanding, there is no such thing as absolute stainless knife. To have something like that, you have to remove iron from steel - which is impossible.
Japanese found a way by polishing the blade into a mirror finish by resisting rust as blades are simple carbon steel like 1045. When the blade has a very smooth surface, oxidation with Iron does not happen that easily. So, this solves one problem but creates another. High reflecting surface does not take any thin coating. When it does, it reflects light still even at very low light, even when blade is quoted in black. For example, CRKT and SOG’s tech bowie diving knife.
I raised this issue because I believe that a knife’s sole purpose is cutting. Out of all the jobs it does as a tool for camper, hiker, soldier etc. cutting is its main job. Currently, I see a lots of blade coated with PVC. That's coating actually hinders the blade’s main purpose. PVC coated does not cut well. I am not saying slicing tomatoes, but even chopping wood. It has a lot less performance than a naked blade. Quite significant if you measure it. Most of these blades are made out of carbon steel which rusts at the speed of light in Asian or tropical countries. For example, most of my TOPS knives. Even with a nice black coating, the edge rusts in matter of weeks. I've to reprofile the edge when I forget to take care of them. Now, tops coated portion is very good. A much better than PVC coating, and a lot thinner than PVC. Cuts better than the PVC coated blade.
To my experience, PVC coating is the worse especially when using the knife for its main purpose. Unfortunately, some of the best knife makers uses this method as it economical and faster process in production.
Chris Reev’s knife has this KG Gun Coat that has very nice finish. Nearly perfect, and very similar to bead blasting but without the side effects of rusting. But not as strong as it eventually comes off. So far best result I’ve seen is stone washed knives. Benchmade folders with stone washed even S30V steel did not rust at all while I was in SEA. But, not sure if it will work on Carbon steel.
So, let me know what you guys think about having the best coat for blade that will rust eventually (no matter how many numbers are there after CPM) but without the side effects of PVC coating. Blade can be non stainless steel, coating should be as smooth as the blade but will not reflect light, so slicing and cutting should be a breeze. I know, I am asking something out of the science fiction movies, but we should get something very close.
Japanese found a way by polishing the blade into a mirror finish by resisting rust as blades are simple carbon steel like 1045. When the blade has a very smooth surface, oxidation with Iron does not happen that easily. So, this solves one problem but creates another. High reflecting surface does not take any thin coating. When it does, it reflects light still even at very low light, even when blade is quoted in black. For example, CRKT and SOG’s tech bowie diving knife.
I raised this issue because I believe that a knife’s sole purpose is cutting. Out of all the jobs it does as a tool for camper, hiker, soldier etc. cutting is its main job. Currently, I see a lots of blade coated with PVC. That's coating actually hinders the blade’s main purpose. PVC coated does not cut well. I am not saying slicing tomatoes, but even chopping wood. It has a lot less performance than a naked blade. Quite significant if you measure it. Most of these blades are made out of carbon steel which rusts at the speed of light in Asian or tropical countries. For example, most of my TOPS knives. Even with a nice black coating, the edge rusts in matter of weeks. I've to reprofile the edge when I forget to take care of them. Now, tops coated portion is very good. A much better than PVC coating, and a lot thinner than PVC. Cuts better than the PVC coated blade.
To my experience, PVC coating is the worse especially when using the knife for its main purpose. Unfortunately, some of the best knife makers uses this method as it economical and faster process in production.
Chris Reev’s knife has this KG Gun Coat that has very nice finish. Nearly perfect, and very similar to bead blasting but without the side effects of rusting. But not as strong as it eventually comes off. So far best result I’ve seen is stone washed knives. Benchmade folders with stone washed even S30V steel did not rust at all while I was in SEA. But, not sure if it will work on Carbon steel.
So, let me know what you guys think about having the best coat for blade that will rust eventually (no matter how many numbers are there after CPM) but without the side effects of PVC coating. Blade can be non stainless steel, coating should be as smooth as the blade but will not reflect light, so slicing and cutting should be a breeze. I know, I am asking something out of the science fiction movies, but we should get something very close.
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