Judy wrote to me with a question:
You said you thread your edges 4-4-3-3, but you weave raising 1&2 together and 3&4 together. Doesn't that leave your edges without warp threads on the underside?
Here is my answer, in case others had the same question. Here is a close-up photo of what she is asking about.
Sorry it took me a while to be able to reply. I had to go back onto the May 23, 2010 blog post, Rag rug weaving tips, to see what I said and then look at old photos to see if I had anything I could show to you. I ended up taking a close-up photo of one of the rugs from that particular warp. Using that technique, my hems are plain weave, 1-3 vs 2-4, which will have each thread separate except the last four edge threads, which will be doubled. When I get to the body of the rug, I weave 1-2 vs 3-4. You are right about the four edge threads all rising or sinking together, acting as one thick thread. They will alternate with the next two warp threads. Take a look at the attached photo. I tried to separate the weft a little right above the red so you could see the four warp threads that the weft is wrapping around. If you don't want to raise four threads together, you could change the last two threads to shaft one or two. The best thing to do is just try it both ways and weave the one you like the best. It is simple to untie the last bundle on each side and re-thread the last two warp threads.