Here is a link to Paul O'Conner's Reference book for double weave. I was just looking at it this morning. He seems to favor the odd and even approach. Nice to have confirmation that using 1-4 for one layer and 5-8 for the other will work. Is there any advantage to odd and even?
Also, in the reference book there is an illustration for having the open end on four shafts come in the middle of the top layer, thus possibly minimizing draw-in a the fold? Does anyone know if this can work on 8 shafts?
I cannot speak from personal experience, but as no one else has replied, here's a possible starting place. In the Best of Weaver's book Twill Thrills, there is a project by Diane Ferguson (pp. 8-9) that uses 8/2 unmerc. cotton warp and 10/2 unmerc.cotton weft set at 24 epi, to yield a "slightly warp-dominant" ticking fabric.
Candace, I apologise if this information seems obvious, but it was not always so to me. The classic Swedish loom design with overhanging beater has beater cradles consisting of separate blocks held onto the uprights by two bolts that fit in a grove. That is, the bolts can be loosened so that the block can slide slightly forward or back. The positon of the block on each side of the loom can be adjusted independently.
What came as a surprise to me was that, to get the beater to hit square, I needed to slide the cradle block back a tad farther on one side than the other. This was just as true of the 5 year old toika as the 30 year old varpa. If you have this setup, adjusting the cradles might help correct for minor warping.