Dagmar,
Thanks for the advice! Some answers/comments:
Kokopelli Design:A heavy waxed thread will help, I think
I usually use Thread Heaven, only resort to beeswax when I'm forced to use a doubled thread, which I avoid if possible. But I don't understand how a heavily waxed thread will help. My tension is already pretty tight. If anything, I suspect it's too tight.
Kokopelli Design: a chopstick not too big in size or you will have problems pulling the thread tight enough.
I've been wondering how to figure out the right size stick, and last night as I was trying to fall asleep, it ocurred to me that I could use an easy proportion to compute the right size. The book recommends a 2mm stick when stitching 3 sides. My tube has 7 sides so the correct size should be 2 / 3 x 7 = 4.67mm diameter stick. My chopstick is 4.84mm, so I'm pretty darn close if that computation is correct. The beadwork is snug, but not tight, on the stick.
Kokopelli Design: Also press the beads from the previous step with your finger to the chopstick while pulling the thread tight.
I've been doing that.
Kokopelli Design: In the first pic the black beads sit nicely together, but the colored beads really look over-crowded. I had these effect when I took colored beads, that are slightly bigger than the others and were too big for their place . When I changed it for a smaller one, the over-crowded effect was gone.
You may have hit upon the problem. All of the beads are Miyuki except for the orange and blue, which are Toho (and typically are a hair smaller than Miyuki). But even among the Miyuki shades, which are the most evenly sized available, the individual colors and finishes vary slightly in size. The pink and purple are probably the smallest Miyuki's of the bunch, and the black and yellow are probably the largest. About half of the columns of black beads line up nicely and about half don't.
Speaking of the columns of black beads, remember first that my choice was a black bead, a bright, and a black for each stitch. In your tube, does the last bead in each stitch sit slightly raised from the first bead in the next stitch? If you look closely at the surface texture of my tube, you can almost see ribs running lengthwise, formed from the last bead in each stitch.
Kokopelli Design: And for the stiffness: don't worry. Flexibility comes increases with the length of the work. It's the same when you stitch an African Helix.
OK, I'll trust you on that. I'm going to swap out the Toho beads and smaller Miyuki beads for larger Miyuki, and then keep going. After I stitch another inch or so, we'll see how it feels.
One other thing, did you sew under the thread in the previous row, and then up through the first bead in the next stitch in the previous row, all in one motion? At the beginning, I used 2 separate motions, then for most of the tube, I used 1 motion, then near the end, I went back to 2 separate motions in case that was causing the problem (I don't think so).
Thanks again for the advice!