What affects bed adhesion the most?

The biggest factors are first layer squish (Z offset), bed temperature, bed surface cleanliness, and the contact area of the part footprint. A clean PEI sheet with correct Z offset gives excellent results for most materials.

Why do tall thin parts lift?

As material cools it shrinks, creating internal stresses that try to pull the edges up (warping). Taller parts have more material shrinking, generating more lift force relative to the small footprint area.

When should I use a brim vs a raft?

A brim adds area around the base and uses minimal extra material. A raft prints a full platform under the part and is better for very warpy materials like ABS or Nylon, or parts with tiny footprints.

Adhesion Calculator

Adhesion Calculator — Contact Area & Force

Estimate the contact area and adhesion force for your print footprint.

Footprint Area

First-layer contact area touching the bed — larger footprints grip far better

Part Height

Total Z height of the part — taller parts accumulate more shrinkage and warp force at the corners

MaterialFilament type — higher-shrinkage materials (ABS, Nylon) warp and lift more than PLA or TPU

Bed SurfaceYour build-plate type — affects how strongly the first layer grips (PEI/BuildTak grip hardest, bare glass and tape weakest unaided)

How We Calculate This

Formula

Adhesion force = Footprint area (mm²) x Surface grip factor
Lift force = Footprint area (mm²) x 0.0001 x Shrinkage factor x Part height (mm)
Safety ratio = Adhesion force / Lift force

The safety ratio is the headline number — it compares how hard the first layer grips against how hard the cooling part tries to peel itself up. A ratio above 2 indicates good adhesion; below 1 means shrinkage forces are likely to overcome adhesion and cause warping or detachment. Taller parts and higher-shrinkage materials raise the lift force, so the same footprint that holds a short PLA part may let a tall ABS part curl off the bed.

About the numbers: the grip and shrinkage factors are relative heuristics calibrated to rank surfaces and materials, not lab-measured Newtons. Real bed-adhesion stress varies by an order of magnitude with bed temperature, Z-offset and cleanliness, so treat the absolute force values as indicative — it is the safety ratio and the recommendation tier that matter. The surface ranking (BuildTak/PEI grip hardest, glass and tape weakest unaided) and the material ranking (Nylon and ABS shrink and warp most, PLA and TPU least) match published 3D-printing guidance.

Frequently Asked Questions

Last updated: February 2026

All calculations are estimates. Always verify settings with test prints before committing to final prints.

Adhesion Calculator — Contact Area & Force

How We Calculate This

Formula

Frequently Asked Questions

Related Calculators

Bed Levelling Calculator

Build Plate Calculator

Brim Width Calculator

Raft Calculator

Bed Temperature Calculator