THE PROCESS
Grinding/Mixing/Spicing-My grinder comes with two different plates that the meat is pushed through after it goes through the cutter. One plate has a bunch of 3/8" (i think) holes and the other has 1/4" (i think). I cut my meat and fat into chunks first and grind all the meat once, using the plate with the larger holes. Then I grind the fat, again using the plate with the large holes.
Then I'll weigh my meat and fat and mix it up in 5 or 10 lb batches. Whatever size fits into whatever containers I have handy. I'll mix the two by hand until they are as mixed as I can get them. Then I'll add the spices and other required ingredients, sprinkling it over the whole mess. Again I'll mix by hand.
Finally I'll regrind and it just depends on my mood which plate I use to grind.
Then I've got my sausage, fat, and meat mixed and I'll store these in a container in the ice chest.
I'll then move on to another batch.
I would not recommend making batches over 10 lbs max because the meat/fat is out too long and it warms up too much.
The spiced meat then needs to sit for 24 hours (chilled) to let the meat soak up the spices.
Often I'll tear off enough of this for a patty and fry it up.
Be warned though, how it tastes then is not how it will taste later, so don't be upset if it's too strong tasting.
At this point I'm usually too beat to do more but you can stuff the sausage into casings before you let it sit for 24 hours.
A word about cure (potassium nitrite) - The brats and italian type sausages I make are considered 'fresh sausage' meaning it is not preserved in any way (smoking, curing, cooking, etc) until right before dinner time. The summer sausage I make is smoked for flavor for 3 or 4 hours and then finish cooked in the oven. Because the meat is brought to temperature very slowly you MUST add potassium nitrite to prevent botulism from forming before it reaches high enough temp. This is not harmful in correct doses and the body naturally produces it. If you are not very careful and overdue the amount then you CAN and WILL get sick. Just double check your measurement for this stuff please. here's a discussion providing more detail.
Wikipedia
Stuffing into Casings-This is the only moderately tricky part of the process. With the appropriately sized tube installed on the end of the grinder I find one end of casing and begin loading it on the tube. I keep working the casings over the tube until I run out of a single piece of casing. Then I tie a knot in the other end of casing and begin feeding the sausage into the grinder/stuffer. You have to be careful not to trap air in the grinder or it will get pushed into casing. If this happens then just pop a small hole in the casing with a toothpick. This is a two person job, at least for me.
With the grinder on slow speed let the meat start filling the casing. You'll have to hold the casing onto the tube and sort of 'force it' to pack it in tightly. You want the casing snug with ssg, but not tight. Otherwise it will burst. This is slow, just take your time.
I let the casing fill about 6 inches then the person feeding the grinder stops putting meat into it for a second and I roll the casing about three turns away from me. I then fill another 6 inches and roll that sausage only TOWARDS ME a couple of turns. This way you don't unravel the first twist you did. This creates the links.
Sooner or later you will bust a casing. I usually scream like a girl until my wife stops the grinder. I'll cut the casing where it burst, leaving enough to tie off the last good sausage, and just start over. No biggie.