FMT,
I noticed in your Texas Hot Links post, your excellent recipe in grams. You list fat back as one ingredient. At my local grocer I've seen packages of fat back in sealed plastic. They appear to have a thin hide on them and then the fat back is about 1/2" thick. Appears you need to slice the hide off of them. Is that what you are using. Do you get pork fat trimmings for your sausage from your butcher? Your sausage work always looks so good and "clean".
There is a butcher in our area that vac seals and freezes approximately 1 pound packs of fat back. His come ready to use, so he must take the skin off for another purpose. They make alot of their own products, and I'm guessing they use the skin for something. What is left is about what you said. A 1/4 to 1/2 inch slabs of pure white fat.
For the pork, I almost always just buy a butt and cut out the gnarly parts to get the best meat.
Thanks for the compliment on the sausage making. I'm getting better and better with each run. Sometimes it doesn't go as well as others, but it usually turns out pretty good. The funny thing is, I actually don't eat all that much sausage. I like the process and recipe development aspect, but usually have a few slices to check flavor then freeze the rest.
I cook the frozen batches when we have birthday parties or get togethers, but rarely eat more than a couple bites myself.