I have finally found somewhere that sells hand-cranked cotton gins, I'm now waiting for a price. There is a choice of two manual ones, small and large, not one in between. Obviously, I'm wanting to avoid any that need a power supply, engine, etc., even though manual is much more work.
It's another one of those examples where you get efficiencies of scale - when you might do a certain amount of work for a certain amount of product, but with only a little more work, you can do a lot more. In this case, the difference in 14 pounds weight in postage, whatever cost for the item itself, to be able to remove the seeds from three or four times the amount of picked cotton.
I'm in a climate that means that I can successfully grow cotton, five bushes are a couple of years old now, two more that I planted last season that have started to produce , and I'm learning a few things about growing them. Cotton isn't without its problems, though. You require about 35 square feet to produce a shirt worth each year. Not that I couldn't plant more and, let's face it, it's currently receiving the processed water out of my home sewage treatment plant.
So, the choice is also one of - will I plant and harvest more? Will I need the extra capability? What cost for the extra size and weight?
If and when SHTF, fabrics will still be available for quite a while - still on bolts, as scraps, as scavenged and repaired clothing. So short to medium term, not as useful as other crops. Why waste space on such if you can't eat it, and you are going to be able to scavenge it for a while? But, as I mentioned, it is receiving the outflow of treated sewage, so the ground that that is going shouldn't be used for food crops anyway, hence my using it for cotton, also some dye plants.
Again, dyes are going to be available if things don't go on too long... but it's nice to grow them anyway.
I think that ginning cotton may have the advantage of being a task that can be done to relax, much like some people sew or knit. Then, I guess, it's a matter of learning how to spin it... And looming...