Best filament for drag chains: flex and wear

The short answerPETG for rigid links. TPU for a flex chain.

A drag chain guides cables through repeated bends. PETG is the pick for rigid link chains that flex at the joints. TPU is the pick for a single flexible chain. PLA is too brittle for the repeated motion.

What a drag chain asks of a filament

A drag chain bends thousands of times, so it needs a filament that resists wear and fatigue. Rigid link chains flex at the joints, so the links must be tough. A one-piece flex chain must bend without cracking. PLA fails both jobs, because it is brittle.

How the materials compare

When to pick PETG

Pick PETG for a rigid link drag chain. The links need toughness and layer strength, and PETG delivers both at 240 to 260 °C. It prints without a heated chamber and holds up to the repeated bending at the joints.

When to pick TPU

Pick TPU for a one-piece flexible chain. The Polymaker PolyFlex TPU95 sheet lists a nozzle of 210 to 230 °C. TPU bends without cracking, so a flex chain survives thousands of cycles where a rigid filament would fatigue.

For the materials, read the PETG guide or the TPU guide. For hinges, see best filament for hinges.