I also agree that the lacquer is a better way to go.
Here's a link to what i posted on this a while ago - my "Chalkryon" experience:
Tempilsticks for annealing
Further on I post on how I managed to make it work and also the advice of Tempil in response to my query as to how to use the "crayons". I didn't think to shave a little off and put it inside the neck; neat idea. I undestand that the 650° F is to measure on the shoulder though and not the neck which should be around 730° or something (just from my research on this and no speciual personal knowledge).
I found that it took a lot longer than 5secs with a propane/butane camping stove cartridge driven plumbing torch (that's a mouthfull). Not ideal as it makes the rest of the case pretty warm.
What torches are you guys using?