Hi Christina! Don’t you love your Pilot? I love mine! I use sewing machine oil. It’s not “eco-friendly” but it is light and doesn’t get too stinky or gooey. I use kitchen vegetable oil for cleaning up ink disk and rollers (plus a final wipe with odorless mineral spirits), but I don’t think vegetable oil would hold up as a lubricant on cast iron and steel. Would be interested to know what you find!