I should clarify,
@LilyD ... I toss the feet, heads, intestines, lungs etc, but do keep Hearts and livers for my cats... I can’t be bothered to clean the gizzards. Everything else is stock material. Excess fat and skin sometimes goes into our chicken kale sausages as well. I’m jealous of your grinder now... what have you got? Our Lem grinder couldn’t handle necks and bones, and our ancient Toledo (has a three digit serial number) is currently being repaired. It’s older than most people here on the farm now.
TOSS THE FEET! Feet are the richest source of Collagen on the Chicken. City dwelling Asian Women pay big bucks for Chicken Foot Broth, just for the Facial Skin Beautifying power of Collagen. Ever wonder why only really Old Asian Women have Wrinkled Skin?
Beyond that, Chicken Feet were Grandma's Secret Ingredient for Full Flavored Chicken Soup. The reason today's generations say, " My Chicken Soup is Good but not anywhere near as good as Grandma's. "
The Collagen in Feet, also denatured into Gelatin. Gelatin in Soup, Sauces and Gravy, is responsible for the Rich, Unctuous, Sticky Lip, Mouth Feel that's just Magical.
Can't be bothered to clean Gizzards? Try Simmering Cleaned Gizzards in you Chicken Soup. They add great flavor. When tender, remove them and let cool. Season them well with Salt, Pepper, Onion Powder, Garlic Powder and Poultry Seasoning. Bread them like for Fried Chicken. Pan or Deep Fry them until Golden Brown and serve. Makes Frozen or Fast Food Chicken Nuggets or Popcorn Chicken taste the like Fried Cardboard! The kids will go Nuts, just don't tell what " part " of the Bird they are. Say they are Dark Meat Nuggets. For the Big Kids, mix a couple of shots of Hot Sauce in Blue Cheese or Ranch Dressing for a Dip, add some Cold Beer to wash them down and they will Bow at Your Feet for more!

Which LEM do you have? The #5-.35hp and #8-.5hp are not rated for Raw Chicken Bones. But, the #12-.75hp or larger will eat through Chicken and even Turkey Bones, cut up, with no issue...JJ