I don't think anyone mentioned that the goal with petroleum jelly soaked cotton balls is to have the PJ on the outside of the cotton ball and to have the inside of the cotton ball DRY (without PJ). That way you can kind of tear the ball inside out and the dry fibers will easily catch a spark, and the PJ will then allow the flame to last longer - like a candle & wick.

I fear use of white gas or other more volatile stuff would simply burn too fast - not to mention that it would be more apt to evaporate in storage and might be explosive under certain conditions.

I've always just used small freezer bags to make & hold the cotton balls. I put a hand full of balls inside the bag, add a glob of PJ, massage until its spread around, open & squeeze out the air, and then seal. It keeps my hands cleaner and makes a great storage container.

One last thought - I do NOT use my knives with ferro rods. I don't want to damage or discolor them. I find the strikers that come with the ferro rods work OK - you can "sharpen" them at a 90 degree angle on a nearby rock, if needed.