In 19th century japan fletchers had small braizers like a metal box with a smaller metatl box passed through it, and open on the ends. A bed of coals was placed in the bigger box, and I believe (i've only seen a sculpture of the device,, not a real one) and the shaft would be passed though the "hole" through the metal channel, and would be thus surrounded by the heat of the coals, but not in contact with them. I think this might work pretty well, for doing this section-by-section.
"(unintelligible word)...after my stay in the earth lodges of the Mandan, I decided to move on in my explorations-but not further west, I decided to take my travels up-to visit the legendary tribes of the Jupiters, those men who dwell on the moons which Galleleo had spied through his spy-glass, and forged a relationship with through the flashing of signal mirrors. My friends say that I am a fool, nay, that I am mad, but as I toil, endlessly glueing together the ailerons and mighty jets of my "thermo-nuclear pulse-rocket" I giggle inwardly to myself. Just wait, you a*******. Just you wait and see, Thomas Jefferson and captain Clarke."
-George Catlin, "the Jupiter Diaries", 1849