Troubleshooting guide

Troubleshooting Guide: Common Issues with Flexible Filaments

Identify and solve the main challenges when printing with Filaflex

We've compiled a comprehensive guide to help make your printing experience as satisfactory as possible. From common issues to expert solutions, find everything you need to achieve perfect prints with flexible filaments.

The Recreus team is always here to help you with any additional questions you might have.

Problem 1 | 'Threads'

When we print with elastic or flexible materials, the first thing that surprises us is the high number of threads that the rapid movements that occur during printing leave us. This is due to the fluidity of elastic materials in their liquid state, and it is an issue that only affects TPUs such as Filaflex. But there is no need to worry! There are several ways to fix it.

Solution
  • Increase the retraction speed of your extruder to the maximum possible. For example at 120 mm/s.
  • Increase the retraction distance to 0.5 mm intervals. For example to 6.5 mm.
  • Increase the traveling speed (fast movements) to the maximum that your 3D printer allows. For example at 160-180 mm/s.
  • Reduce the temperature of the Hotend to the minimum possible without clogging it, in intervals of 3º C.
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Threads Problem Example

Problem 2 | 'Insufficient extrusion'

Sometimes, we can perceive that the extrusion lines are not well defined, have bald spots or are very poor. This is usually caused by an insufficient extrusion problem and can be solved by adjusting a series of parameters.

Solution
  • Hotend temperature increase of 3-5ºC. Sometimes this problem is solved by increasing the temperature.
  • Increased pressure on the filament in the extruder. Sometimes the pressure on the filament is insufficient and it slips, thus preventing a continuous and stable extrusion.
  • In the 'slicer' software, use the 'extrusion multiplier' and increase it to a value of 1.3 although it will depend on the extruder you have.
  • Also reducing the speed may help to extrude more material.
  • Check and clean the nozzle, since it may be partially blocked, especially when you have changed from a rigid material such as ABS, PETG, etc., to a flexible one. In this case, increase the extruder temperature up to 260ºC and extrude Filaflex until it comes out very fluid and without stains.
  • Reduce the humidity of the filament. Dry the filament for 2 hours at 45-50ºC in a conventional oven with activated air circulation.
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Insufficient Extrusion Example

Problem 3 | 'Holes in the upper layers'

It can also happen that our printed piece has good quality, but in the upper layers, we find holes or small bumps. Next, we will detail the solutions to this problem.

Solution
  • Increase the number of upper layers, the recommended minimum is 4, but you can increase to 6 or 7 more.
  • Increase the fill/infill percentage. Sometimes the material cannot close the top layers in pieces with very low fillings. For example: 12%, onwards.
  • Reduce the Hotend temperature in 5ºC sections. Sometimes when the material is very hot, due to its high fluidity, it is unable to close the upper layers.
  • Increase the layer fan speed to 100%.
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Holes in Upper Layers Example

Problem 4 | 'Insufficient filling'

On the other hand, it may be the case that we appreciate that the filling of our printed piece is inconsistent, but at the same time, the perimeters are well made. In this case, we can solve it as follows.

Solution
  • Reduce the filling speed and match the speed of the outer perimeters.
  • Increase the temperature in 5ºC sections, until the optimum is found.
  • Increase the arm pressure on the extruder.
  • Increase the 'extrusion flow' by 5%.
  • Reduce the humidity of the filament. Dry the filament for 2 hours at 45-50ºC in a conventional oven with activated air circulation.
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Insufficient Filling Example

Problem 5 | 'Curved perimeters'

When we are printing parts that have a high overhang angle (angle of the horizontal protrusion), we run the risk that the perimeters may curve upwards and cause the next layers to be poorly deposited. How can we solve it?

Solution
  • Reduce the speed of the perimeters to 15-20 mm/s.
  • Change the nozzle for a more pointed or sharp one.
  • Reduce the speed of the layer fan to 0%.
  • Reduce the temperature of the hotend to the optimum minimum possible in 5ºC intervals.
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Curved Perimeters Example

Problem 6 | 'Unjoined perimeters'

On certain occasions, we appreciate that the outer perimeters of the printed piece are not joined together. But this is a detail that we can solve in the following way that we will see below.

Solution
  • Reduce the speed of the perimeters to 15-20 mm/s.
  • Increase the temperature in increments of 5ºC.
  • In the printing software we can indicate that the nozzle has 0.05 mm less. For example: 0.4 nozzle, we indicate 0.32-0.35 nozzle (with the 'Slicer' software).
  • Check and clean the nozzle, since it may be partially blocked, especially when you have changed from a rigid material such as ABS, PETG, etc., to a flexible one. In this case, increase the extruder temperature up to 260ºC and extrude Filaflex until it comes out very fluid and without stains.
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Unjoined Perimeters Example