Meat Grinder Bone Fragments and Sinew: Which Grinder Heads and Plates Handle Tough Wild Game Trim

Grinder knives and coarse grinding plates for wild game · October 27, 2026

Why sinew and silverskin wrap the auger and knife

A grinder works in a fixed sequence. The auger (the worm screw) pulls meat down the throat of the head and pushes it against a rotating knife, and the knife shears it against the flat face of a stationary plate. That shearing action cuts muscle fibre well. It cuts long, elastic connective tissue badly.

Silverskin is the thin, shiny membrane over the hindquarter muscles and backstrap. Sinew is the tendon and heavy fascia found in shanks, neck and shoulder trim. Both are tough strands, not soft fibres. The auger drags them toward the centre of the plate, where the knife hub turns. Pieces longer than a plate hole are not cut cleanly. They are pinched at the hole edge and then wound around the knife hub and auger tip.

Once a mass of sinew builds up on the knife, it lifts the knife blades away from the plate face. Cutting stops and the meat is squeezed through the holes as paste. That is the same smeared texture that warm fat produces, but the cause is mechanical rather than temperature.

Recognising a wrapped knife while you grind

The signs show up well before the grinder stalls. Output slows even though the auger is turning at full speed. Ground meat leaves the plate as short, mushy extrusions instead of distinct strands with visible fat and lean. The motor note drops and the head warms up at the plate end.

Stop and take the head apart when you see these signs. A grinder that keeps running with a wrapped knife works the meat into a paste and loads the gearbox and bearing for no gain. Unscrew the retaining ring, pull the plate and knife, and look at the hub. A tangled wad of pale, stringy tissue around the knife centre confirms the cause.

If the grinder has a reverse switch, a short reverse burst can back out a light jam. Heavy sinew wraps still need the head disassembled and cleaned by hand. Do not use reverse as a way to keep grinding unsorted trim.

Trim first: the step grinder hardware cannot replace

No plate or knife fully compensates for silverskin left on the meat. The most effective step is removing it before the meat reaches the throat.

Use a thin, flexible boning knife. Slide the tip under the silverskin, angle the edge slightly up toward the membrane, and pull the knife along while holding the loose end taut. Keep the blade against the membrane rather than the muscle, so you lose little meat. Heavy sinew on shanks and neck is harder to separate. Cut the meat away from the tendon and discard the tendon rather than feeding it through.

A few practical habits help:

Trim while the meat is firm and cold, because a membrane holds its edge better against the knife.
Cut cubes small enough to enter the throat without being forced by the stomper.
Feed one cube at a time and let the auger clear the head before adding the next.
Discard silver-white strands that survive cubing, rather than hoping the plate will deal with them.

Plates, knives and the choice that actually matters: edge and contact

Plate hole size gets most of the attention, but for sinew the key factor is how cleanly the knife edge meets the plate face. A sharp knife pressed flat against a flat plate cuts strands as they cross the hole edges. A dull knife, or one with a worn plate face, folds strands over the holes instead.

Three specifics decide this. First, the knife and plate must match the head size (#8, #12, #22, #32), because a mismatched hub leaves a gap at the face. Second, check that the knife edges face the plate when assembled, since a knife installed backwards will not cut at all. Third, the retaining ring should be tight enough to hold the knife against the plate, but not so tight that metal-on-metal friction heats and galls the parts.

If the plate has dished or scored areas, strands can slip underneath it and wind around the knife. A flat, undamaged plate does better than a new but poorly finished one. A knife that seats on the plate with no visible light gap around the edge is working properly.

Coarse plates, fine plates and a two-stage grind for tough trim

A coarse plate, with larger holes in the 3/8 inch range, gives trim more room to pass through and puts less pressure on the knife. A fine plate with holes around 4.5 mm (3/16 inch) is much more likely to clog on connective tissue, because each hole is a narrow slot that a single strand can block.

That makes a two-stage grind the most reliable approach for wild game that includes some tough trim. Run the meat through the coarse plate first. Inspect the output and pull out any pale strands you can see. Then regrind through the fine plate if you want a finer texture for burger or sausage. Fine plates on the first pass are where sinew wraps and smearing occur most.

A kidney plate, the large-hole stuffing plate, is designed for mixing and stuffing, not for cutting. It is not a substitute for a coarse cutting plate when the trim contains connective tissue.

Bone fragments: what a grinder is and is not built for

Standard meat grinders for wild game are built to cut boneless meat and fat. They are not bone grinders. Small bone chips, usually left from saw cuts or from meat trimmed off the bone in a hurry, can chip a knife edge or scratch a plate face. Even a minor nick lets strands slide past unsheared, which makes the sinew problem worse.

Check cubes by feel as you trim, especially around rib meat, neck and the cut ends of quarters. Bone dust and splinters are hard to see in ground meat, so removing them before grinding is the only dependable method. A hard crunch or a sharp rattle from the head means stop and inspect. Do not push on.

Bone also marks the limit on grinder power. A higher-horsepower motor drives the auger harder, but it does not turn a meat grinder into a bone crusher. If you want bone-in grinding for pet food or similar, that calls for equipment made for the purpose.

Sharpening, replacing and cleaning after tough trim

Sinew wears the knife edge faster than lean meat does, and a wrapped hub has often been dragged against the plate face. After a heavy session, check both parts. Run a fingertip carefully along the knife edge and plate face. Rounded blade edges, nicks, or a dished plate mean the pair is no longer cutting.

Some owners lap a plate and knife flat on a sheet of fine wet/dry sandpaper laid on glass, using a figure-eight motion. That restores a flat face when wear is slight. Deep grooves or a chipped knife are better replaced. Because plate and knife wear together, replace them as a pair when you can.

Clean sinew out of the plate holes immediately with a wooden skewer or a small brush. Tissue that dries in the holes hardens and blocks them on the next grind. Dry the parts completely and coat cast iron or tinned aluminium with food-grade oil to prevent rust. Wash aluminium by hand, since a dishwasher darkens and pits it.

FAQ

Why does my grinder turn venison into paste instead of strands?

Usually either the meat is warm and the fat is smearing, or sinew has wrapped the knife and lifted it off the plate. Disassemble the head and check for stringy tissue around the knife hub. If it is clean, check that the knife is sharp and seated flat against the plate, and chill the cubes before grinding.

Does a coarse plate handle sinew better than a fine plate?

Yes. Larger holes give strands room to pass through and are less likely to block. For tough trim, grind coarse first, remove visible sinew, and then use the fine plate only if you need a finer texture.

Can I grind small bone pieces left in venison trim?

No. Standard grinders are made for boneless meat, and bone chips can nick the knife and scratch the plate, which makes sinew wrap worse. Remove bone and splinters at the trimming stage.