Hmm interesting point about the 15 mm ID tube, I did'nt think of that, glad I switched to the 6mm rod, that was hard enough on my hands.
My method was to hold the tube in my right hand with my thumb over the capped end, then strike it firmly down on a hard surface, make a quick grab for the rod end and pull it out, hopefully with a glowing ember, which most of the time there was.
I think a bigger diameter would work better for holding, but not for compression, so I guess the easiest solution would be to encase the 8mm tube in something like 25mm dia or bigger wood, that way the whole thing can be held in the hand, should make for a quicker withdrawl as well, so more likely to have an ember.
I think I'll have a play tomorrow.
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