Freeze your venison and pork fat pieces for ~30-60 minutes after cutting into grinder size pieces.
Grind the meat through coarse plate.
Mix your seasonings into your meat by hand and put back in the freezer for ~30-60 minutes.
Grind the meat again switching to a fine plate.
Freeze the meat again for ~30-60 minutes.
Depending on how big your food processor is you might need to work in batches.
Place half of your meat into your food processor with half of you ice water.
Pulse for ~2 minutes until it turns into a thick paste/emulsified mixture.
Remove from the food processor and place into your sausage stuffer.
Make sure the mixture stays below ~40°F. Keeping the mixture that cold will stop the fat from smearing.
Place the other half of your meat mixture and ice water into your food processor and repeat the process.
Once all of your meat is into the sausage stuffer, punch down the meat to try to get out as many air pockets as possible.
Place your cellulose casings onto your stuffer. Push the casings all the way back until you run out of space. The casings should be ~1 inch in diameter so you need a stuffer under ~1 inch to fit.
When you run out of space cut your casings and tie it off at the end. I used kitchen twine to tie it off.
Preheat your smoker to 180°F. I used a competition blend of pellets, but most fruitwoods would work well here.
Start stuffing your casings, two people makes this process a lot easier. If you have any blowouts in the casings just cut the casings, pinch out some of the exposed meat, and tie it off again at the end with kitchen twine.
After you have all of your sausage in casings, and tied off at both ends, you can twist them at your desired hot dog sizes. I found that using kitchen twine to tie off each hot dog, at ~6-8 inches, worked fine without needing to twist each dog to and away from you.
Put your hotdogs onto your smoker. If you have a vertical smoker where you can hang them that works. If you have a regular one you can place them flat on that works too.
Smoke for ~3 hours or until the hot dogs have reached 155-160°F. If you have an ugly or tiny hot dog wait for ~45 minutes and then stick your probe into that one to get a temp.
Remove your hotdogs and immediately place into an ice bath, for a few minutes, to stop them from cooking and to also make the cellulose casings easier to remove.
Remove from the ice bath and pat dry. Place into a fridge to let cool overnight.
Remove the hot dogs and pull the casings off of them. Most should come off easily, but some you might need a knife to make an initial cut.
Cook your hot dogs on the grill, fry on a pan, boil them, or store them for later use.