I have my Mothers old Singer machine. A real deluxe model. Mom sewed all kinds of things new from scratch and repairs. I remember a little about using it but never saw Mom attempt working with leather.
Snow Seal got hard to find so I bought a 32 oz quart "paint can" of it. Years supply and co$t$ much le$$.
You can order the Limmer boot grease direct from Limmer. It conditions the leather and waterproofs it but does not make it too soft/pliable. Great stuff to treat boots/shoes in the area that bends a lot right behind your toes, keeps leather from drying out and cracks from starting
For animal fats you need to cook/render it. After you cook the fat and separate the cracklings (think bacon grease), Boil it with a few changes of water and pour it off each time. Cleans all the water soluble materials out and many things which make fat taint. Can put it up in canning jars.
Time permitting, and if my hunting skills shine this fall,I might try putting up some deer or bear fat. Then experiment with uses. I suspect a good mixture will behave like the Limmer boot grease.
Some people use animal fat mixtures for patch lube shooting round balls out of traditional ML rifles/shotguns.
I started saving my bacon fat for cooking with. Good smoked bacon from local pigs without any additives. That I just pour off into a clean soup can or canning jar and keep in the frig for cooking with. Has cut way down on the amounts of butter and olive oil I use.
Works great for frying in the seasoned cast iron skillet on top the woodstove, even eggs don't stick.
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