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- Nov 27, 1998
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I posted this pic on the "What 'Traditional Knife' are ya totin' today?" thread least week, and it received a lot of interest and questions, so I thought I'd post the very simple procedure I used to get this dark, even forced patina on my GEC Northfield (polished) #72 in 1095. If the Mods in their wisdom choose to move this to the Maintenance, Tinkering & Embellishment board, so be it, but I wanted my friends at the Traditional board to be aware of it.
What you'll need:
Mask the handle material if it's stag, bone, or horn, etc. The vinegar can leach out the natural oils and dye, so try to keep it away from the handle scales. The ebony on my knife became slightly dry in spots, but it was good as new after a drop of lemon oil. If you do get any drying or discoloring, treat the scales with the appropriate moisturizer (mineral oil, lemon oil, etc.).
Clean the blade and/or springs thoroughly with the alcohol. Wipe dry and keep your fingers off the steel.
Pour enough cider vinegar into a small saucepan to cover the bottom, and carefully bring it to a boil. Good ventilation is a plus; it's smelly stuff.
Hold the cotton ball with the tongs, dip it in the pan and wipe down the steel from end to end with the hot vinegar repeatedly until the steel turns black. Keep dipping the cotton in the hot vinegar and wiping (about three to five minutes) until the steel color won't darken any further.
Use a folded paper towel to smoothly wipe away the vinegar on the steel in one smooth linear motion to avoid streaking or blotching. If the wipe doesn't result in a uniform color, apply more hot vinegar and try again. Wipe away any remaining vinegar from the handle and let dry.
Edit: Instead of trying to wipe away the vinegar to avoid streaking, just rinse it away with cold running tap water to neutralize the oxidization process, as noted in post #22. Dry thoroughly and oil.
At this point, your steel finish will probably still show some streaking or unevenness, so gently polish the surface out with a little of the silver polish until it's a uniform light-to-medium gray. Wipe off any residual polish, clean the steel thoroughly again with alcohol, dry and repeat the hot vinegar process, again being careful to wipe away the last vinegar treatment in a smooth, linear swipe.
Repeat the whole process as needed until the steel is uniformly blackened, with no streaks, voids or blotches. It's easier to do the springs and blade(s) separately, rather than trying to do everything in one session. Wipe the steel down with a liberal dose of oil when you're finished to remove any remaining vinegar and seal the deal.
Hope this was useful. Have fun, and take your time.

What you'll need:
- Apple cider vinegar
- Cotton balls and paper towels
- A pair of tongs or large tweezers
- Non-abrasive silver polish
- Rubbing alcohol, naphtha (lighter fluid) or acetone, etc.
Mask the handle material if it's stag, bone, or horn, etc. The vinegar can leach out the natural oils and dye, so try to keep it away from the handle scales. The ebony on my knife became slightly dry in spots, but it was good as new after a drop of lemon oil. If you do get any drying or discoloring, treat the scales with the appropriate moisturizer (mineral oil, lemon oil, etc.).
Clean the blade and/or springs thoroughly with the alcohol. Wipe dry and keep your fingers off the steel.
Pour enough cider vinegar into a small saucepan to cover the bottom, and carefully bring it to a boil. Good ventilation is a plus; it's smelly stuff.
Hold the cotton ball with the tongs, dip it in the pan and wipe down the steel from end to end with the hot vinegar repeatedly until the steel turns black. Keep dipping the cotton in the hot vinegar and wiping (about three to five minutes) until the steel color won't darken any further.
Use a folded paper towel to smoothly wipe away the vinegar on the steel in one smooth linear motion to avoid streaking or blotching. If the wipe doesn't result in a uniform color, apply more hot vinegar and try again. Wipe away any remaining vinegar from the handle and let dry.
Edit: Instead of trying to wipe away the vinegar to avoid streaking, just rinse it away with cold running tap water to neutralize the oxidization process, as noted in post #22. Dry thoroughly and oil.
At this point, your steel finish will probably still show some streaking or unevenness, so gently polish the surface out with a little of the silver polish until it's a uniform light-to-medium gray. Wipe off any residual polish, clean the steel thoroughly again with alcohol, dry and repeat the hot vinegar process, again being careful to wipe away the last vinegar treatment in a smooth, linear swipe.
Repeat the whole process as needed until the steel is uniformly blackened, with no streaks, voids or blotches. It's easier to do the springs and blade(s) separately, rather than trying to do everything in one session. Wipe the steel down with a liberal dose of oil when you're finished to remove any remaining vinegar and seal the deal.
Hope this was useful. Have fun, and take your time.
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