TPU is the filament most beginners try once, fight with, and put back in the drawer after a print full of stringing, skipped extruder steps, or a jam halfway through. Almost all of that comes down to running TPU with settings copied from PLA or PETG instead of settings built around a soft, flexible material. This guide covers the nozzle and bed temperature ranges TPU spools fall into, why a direct-drive extruder makes such a large difference over a Bowden setup, retraction, print speed, and how a spool’s Shore hardness rating changes all of the above. For how TPU compares to other filaments before you buy a spool, see the 3D printer filament types guide. For a direct head-to-head against PLA and PETG on flex versus rigidity, see the TPU vs PLA and PETG comparison.
Nozzle temperature: why the range depends on the spool more than a rule of thumb
TPU generally prints somewhere between 210°C and 240°C, but brand and formulation move that number around more than you’d expect from hardness alone. Polymaker’s PolyFlex TPU95, a 95A shore filament, lists 210-230°C on its data sheet. MatterHackers’ Pro Series TPU calls for 220-240°C. NinjaTek’s NinjaFlex, one of the softer common TPUs at 85A shore, actually recommends a higher 225-250°C, which cuts against the assumption that softer filament automatically wants less heat. In practice, hardness affects how the filament feeds and flows more than it dictates melt temperature, and brand-to-brand formulation differences matter just as much. Start at the range printed on your spool rather than a generic hardness-based number.
Bed temperature: TPU doesn’t need much heat to stick
Most TPU sticks well with a bed temperature of roughly 40-60°C, well below what ABS wants and even below what PLA sometimes needs for tricky parts. Because TPU is flexible, it grips a wide range of surfaces (textured PEI, glass with a thin glue stick coat, painter’s tape) without needing high bed heat. A reasonable starting point is around 50°C, adjusted up or down in 5°C steps if the first layer isn’t holding or is holding too well. An overheated bed can work against you here too: it can bond the first layer so aggressively that removing the part becomes difficult, or soften and deform the bottom layer under its own weight.
Direct drive vs Bowden: why extruder type matters more for TPU than anything else you print
A Bowden setup pushes filament through a meter or more of PTFE tube before it reaches the melt zone. Rigid filaments like PLA transmit push force through that tube without much trouble. TPU is soft enough that the same push force just compresses and coils the filament inside the tube instead of advancing it cleanly, and that gets worse the moment retraction is layered on top. A direct-drive extruder puts the drive gear within a few millimeters of the melt zone, so there’s almost nothing for the filament to buckle into before it’s pushed through. That’s a large part of why printer makers who officially support TPU either ship a direct-drive setup or recommend upgrading before running flexible filament on a Bowden machine. See the direct drive vs Bowden extruder guide for the tradeoffs of each setup beyond TPU specifically. A Bowden printer can still run TPU, just at lower speed with a short, well-secured tube path, and softer grades around 85A tend to give more trouble on Bowden than stiffer ones do.
Retraction: minimal or off, not tuned like PLA
Because TPU compresses instead of retracting cleanly, it wants much less retraction distance than PLA or PETG, sometimes none at all. On a direct-drive setup, keep retraction short, roughly 0.5-3mm at a slow 20-40mm/s, rather than the larger distances that work fine on rigid filament. On a Bowden setup, retraction has to be bigger to clear the longer tube, commonly cited around 4-6mm, but that extra distance is part of why TPU jams or grinds through the drive gear on Bowden printers more often than on direct drive. If you’re seeing strings, the instinct carried over from PLA is to add more retraction. With TPU, try lowering it first: treating TPU stringing like a PLA problem and cranking retraction up usually makes jamming worse instead of fixing the strings.
Print speed: why fast settings don’t work on a soft filament
TPU generally wants to print slow, somewhere around 20-40mm/s, well under the 40-60mm/s or faster you might run on PLA or PETG. Because TPU is soft, it compresses along the extrusion path before it reaches the nozzle opening; pushing it faster doesn’t move more plastic through, it just leads to under-extrusion or the extruder motor skipping steps. Consistent, slow speed matters more for TPU than for almost any other filament, and first layers usually want to run even slower to keep flow steady while the bed is still finding grip.
Shore hardness: 85A vs 95A and what actually changes
Shore hardness measures how flexible or rigid a TPU grade is, and a lower number means a softer material. Common grades run from around 85A, soft and stretchy, up to around 95A, which behaves closer to a semi-rigid plastic than to a rubber band. Softer grades around 85A flex more and suit gaskets, wearables, and anything that needs real give, but they’re also harder to feed consistently: they compress more easily inside the extruder path and are more prone to distorting before they reach the melt zone, which usually means slower speed and more conservative retraction than a stiffer grade needs. Stiffer grades around 95A feed more predictably, tolerate a bit more retraction, and can often run closer to (though still well under) PLA speeds, at the cost of feeling less soft in the finished part. Starting with something closer to 95A generally gives more margin for error on a first TPU print.
TPU settings checklist
- Nozzle temperature set within roughly 210-240°C, matching the range printed on the spool.
- Bed temperature around 40-60°C, adjusted for grip rather than pushed high.
- Direct-drive extruder used where possible; Bowden printers run slower with a short, secured tube path.
- Retraction minimal (roughly 0.5-3mm on direct drive) or disabled, not increased to fight stringing.
- Print speed kept low, roughly 20-40mm/s, well under typical PLA or PETG speeds.
- Softer grades (around 85A) treated more conservatively on speed and retraction than stiffer grades (around 95A).