Low-profile or flat parts get clipped by the sweep

If your parts are shorter than roughly 15 mm and the toolhead is clipping or crushing them during the push sweep, you’ve hit the low-profile edge of what Stage 1 can handle comfortably. This article covers the config fix, when to split plates by height, and when to upgrade.

Symptoms

3, 5, or 10 mm keychain and token parts: toolhead hits them on every loop regardless of z-offset
Larger flat parts at 6 to 10 mm tall: release fine, but the sweep clips them on the way back
Plates with mixed-height parts: the tall parts sweep correctly, the short parts stay on the plate untouched
Toolhead crossbar crushes a part while moving to the back of the bed at the end of a loop

Why this happens

The sweep has a single Z height per loop. On older app builds that height was fixed at 2 mm above the tallest part. Newer builds default to 5 mm, which clears most low parts but is still a single number. If the plate has a 40 mm part and a 4 mm part side by side, the sweep clears the tall one and rides straight through the short one.

Fix 1: manual push-height slider

The FarmLoop app now exposes a push height setting under Detachment Tuning (early 2026 release).

Default is 5 mm, good for most parts
For parts between 8 and 15 mm tall, try 3 mm
For parts under 8 mm, try 2 mm
Parts under 5 mm can go to 1 mm, but the safety margin for z-axis skip disappears at that point, see the warning below

Step down in 1 mm increments and run a single-loop test between each step. Watch the first push carefully and abort if the toolhead touches the part.

Fix 2: adhesion matters more for short parts

Short parts have no leverage. If a tall part resists detachment, the bend can still flex it off; for a short part, the part must release passively before the push sweep starts, because the push has nothing to push against.

Apply the parts-won’t-detach fix stack doubly hard:

Z-offset at 0.00 to +0.04 mm, not negative
Cooldown threshold 4 to 6 °C below what intuition says
Increase bottom layers to 5 or more, a stiff thin part pops; a flexible one bends with the plate
Textured PEI, never Frostbite or SuperTack, see choosing a build plate

Fix 3: plate layout

When a plate has mixed-height parts, you have three options:

Split onto separate plates grouped by height, and run them as sequential loops at different push heights
Place taller parts toward the back, shorter toward the front, so the sweep handles the tall ones first during the return pass (works for small height differences only)
Match heights by adding a sacrificial skirt under short parts to raise their top surface to match the tall parts, discard the skirt after

Option 1 is the most reliable. The FarmLoop app queues multiple plates back to back, so “split into two plates” doesn’t cost you wall-clock time.

For parts under 8 mm: plan on Stage 2

Stage 1’s leverage scales with part height. Below roughly 10 mm the passive bend barely exerts force on the part edges; below 5 mm it effectively cannot detach at all. Stage 2’s active linear actuator bends more aggressively while the z-axis stays locked, which changes the math for small parts.

If your business is small flat parts (labels, keychains, game tokens, magnets), Stage 2 is a prerequisite, not an upgrade. The ROI on the kit versus the cost of failed prints is usually weeks, not months.

Sweep clearance at the back of the bed

For any part longer than about 180 mm in the Y direction, leave at least 30 mm clear at the back of the plate. The sweep accelerates through that space, and a part too close to the back will be hit at speed.

When to contact support

You’ve lowered push height to 1 mm, applied all adhesion fixes, the part still gets clipped: the part geometry is likely outside Stage 1’s envelope, email a photo or STL to contact@3d-farmers.com for a sanity check before committing to a production run
You’re considering Stage 2 for a specific part shape: the support team will test it in the FarmLoop farm before you commit to the kit