Yes, three. I pulled with warm shellite 100ml each time, 400ml total (I remember now that I did it four times), and froze after. I also heated the vinegar and bark and strained three times at the start.

Do you think the temperature was too low? Should I have aimed for more of a boiling simmer? I could put my hand into the water, and it was fine, like a very warm bath.

I can use heptane again, Zippo lighter fluid, or Xylene. Which would you recommend?

Thanks for your help!