Etching: Making the black stay!?

[slowjett]

Hey guys. Im finishing up ome knives i have made for the groomsmen in my wedding. Im using chainsaw chain, some pure chainsaw chain, some chain layed ontop of 15n20. Got one more to etch. But Whats the best way to get the black to stay? So far I've soaked in acetone after the ferric chloride bath and thats helped keep some of the darker areas more black. But it still comes off a lot. I dont want it coming off if they cut an apple in two!

thanks!
Josh

 

[sunshadow]

boil the blade in a saturated solution of baking soda and water for 20 minutes, then rinse thoroughly, dry and oil

that's how I did it on these ones

http://www.sunshadowdesign.com/knives/index.html

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