TPU Settings for Longer LK5 Pro

Temperature Settings

Start with the nozzle at 225°C and the bed at 50°C. If you see poor layer adhesion, increase the nozzle temperature by 5°C increments. If you experience stringing, decrease the nozzle temperature by 5°C. For the first layer, you can increase the bed temperature by 5°C for better adhesion, then let it drop back to 50°C for subsequent layers.

The TPU filament has a recommended nozzle temperature range of 210-240°C and a bed temperature range of 40-60°C. The Longer LK5 Pro supports nozzle temperatures up to 260°C and bed temperatures up to 110°C, which fully covers the recommended range for this filament.

Speed & Quality

For the Longer LK5 Pro, a print speed of 20-50 mm/s works well with TPU. The first layer should be printed at 15-25 mm/s for solid bed adhesion. Outer walls at 70-80% of the main speed produce cleaner surface finishes.

For quality-critical prints like miniatures or display pieces, reduce the speed to 20 mm/s and use a 0.12-0.16mm layer height. For draft or rapid prototyping, you can push the speed to 50 mm/s with a 0.24-0.28mm layer height. The standard 0.2mm layer height at 35 mm/s provides the best balance of speed and quality for most prints.

Bed Adhesion

TPU adheres well to most surfaces including PEI sheets, blue painter's tape, and glass with glue stick. Adhesion is rarely an issue with TPU.

Common Issues with TPU on Longer LK5 Pro

Here are the most common problems you may encounter when printing TPU on the Longer LK5 Pro, along with proven solutions:

• Filament jamming: Reduce print speed significantly; check extruder path for gaps where flexible filament can buckle
• Stringing: Reduce temperature, increase travel speed, and reduce retraction distance (less is more with TPU)
• Under-extrusion: Increase flow rate by 5-10% and slow down the print speed
• Grinding filament: Reduce retraction distance and check extruder gear tension

Tips for Best Results

Follow these expert tips to get the best possible prints with TPU on your Longer LK5 Pro:

• Speed is the most critical setting -- printing too fast is the number one cause of TPU failures
• A direct drive extruder is strongly recommended; Bowden setups struggle with flexible filaments
• Minimize retraction (0.5-1mm on direct drive) -- excessive retraction causes jams
• Dry your TPU before every use in humid climates; it is very hygroscopic
• Consider starting with Shore 95A TPU -- it is the easiest flexible filament to print

Support Settings

For prints requiring supports with TPU, use tree supports for easier removal and less scarring. Set a 0.15-0.2mm Z-distance between support and model. If you have a dual-extruder setup, consider PVA (for PLA/PETG) or HIPS (for ABS) as dedicated water/solvent-soluble support material.

TPU at a Glance

Longer LK5 Pro Specifications

The Longer LK5 Pro features a 300 x 300 x 400 mm build volume with a maximum print speed of 180 mm/s. It uses a Bowden extruder system, which is lighter on the print head but may require additional tuning for flexible filaments like TPU. The hotend can reach 260°C and the heated bed supports temperatures up to 110°C.