Warping tiles

How about making a cutter that compensates?
I could do a 3D drawing to 3D print one for testing.
Maybe it is not the centre pushing out but the sides pulling in.

What would happen if you waited for a while before cutting?
I assume you are extruding as stiff as possible.
lignosulfonate

I think this is one of the reasons for including lignin in tile and brick clay recipes, the clay takes less energy to extrude and has fewer laminations and internal stresses.
Deepseek: The root cause is now almost certainly differential extrusion speed and compression release within the die itself. In essence, the trailing edge bows because it's a snapshot of the velocity profile of the clay inside the die at the moment of cutting. The fast-moving center bulges out.

Technicians give you a printout but those points don't apply here.
-The clay is not being cut by a wire, but using a cookie cutter after extrusion.
-The warpage is unusual, the tile stays flat, just the trailing edge bows outward as shown (regardless of orientation in drier).
-The pugmill and die are new. The die was purpose-designed for this.
-The leading edge of the tile should be bowed inward also (if velocity profiles in within the die are differential).
-The moisture is equal from and back.

This is exactly what's happening in your cookie-cutter die:

1. Fast Center Flow: The clay in the very center of the tile's shape has the shortest, most direct path to escape the die. It experiences the least friction and wants to extrude the fastest.
2. Slow Corner/Edge Flow: The clay that ends up at the trailing edge (and all other edges) has to make a 90-degree turn to fill the corners of the square die. This creates more resistance and friction, slowing its progress.

When the clay column is moving forward, this isn't a problem because it's one continuous mass. The problem is revealed the moment the cutter hits.

· Add a "Relief" or "Draft" Angle: Instead of the die walls being perfectly perpendicular (90°) to the extrusion direction, taper them inward. A 2-5° taper will reduce the friction on the clay as it flows into the corners, allowing it to move faster and match the center's speed.
· Implement a "Land": Don't let the clay exit immediately after the shape is formed. Add a short, parallel section (a "land") after the shaping area. This allows the fast-moving center clay to rub against the slower-moving edge clay inside the die, equalizing the pressure before it exits. Even a 1/4" (6mm) land can make a massive difference.
· Chamfer the Exit: A simple and immediate fix is to chamfer or bevel the exit edge of the die, particularly on the inner face. This reduces the "drag" at the very last moment and can help the trailing edge release more cleanly.

· Stiffer Clay: A slightly stiffer clay (lower water content) will be less fluid and have less tendency to continue flowing after the cut. It will hold the shape imposed by the die more faithfully.
· Shorter Clay: If your clay is very long and stringy (high plasticity), it can exacerbate this effect. Adjusting the recipe with less plastic clay or adding a non-plastic filler like grog or fine sand can reduce the elastic recovery and "squish."

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