Put the fat in a crock pot, or in a pot with water in it to boil. Simmer at low heat, until the fat reduces to oil, which floats on the top of the water. The smaller the chunks of fat, the faster you reduce the fat to oil. Do NO over-cook.
Use a strainer to remove the remnants of the fat from the liquid, and pour the liquid thru a sieve lined with layers of cheesecloth, or paper toweling, or coffee filters, etc. to separate out the solids and trash from the water and oil.
Pour the liquid in jars, and let them cool. The water will settle to the bottom, with the oil on top.
The water will contain any salts or enzymes, that might have been in the fat, so by removing the water from the oil, you clean the oil. A cheap, plastic "turkey baster" can be used to separate the oil from the water while its warm.
Let the oil sit in a closed jar, to cool, as there will be solids( white in color) that will float on the top and resemble lard, while the oil settles to the bottom. This can take several days or even weeks.
You can spoon(skim) off the solids and reheat them to render more oil from it. The more the warm oil is filtered, the fewer solids will be left in the oil.
If YOU HAVE Managed to NOT burn the oil, it will have a very LIGHT YELLOW color to it, not much different than the oil you see being sold in the grocery stores.
If you DID burn the oil by cooking the deer fat too hot, just filter the oil several times. It may be a little darker than what it could have been, but its still oil, and can be used, certainly, for a patch lube mix.
