Source: E3DOnline via Twitter

TPU can be a difficult material for 3D printing, but using the right temperatures is part of a successful start. Read on to find the best printing temperatures on TPU!

While PLA, PETG and ABS predominate when it comes to 3D printing threads, all of these materials are relatively rigid. Thermoplastic polyurethane ( Thermoplastic polyurethane), better known as TPU, is a popular material for 3D printing, known for its natural flexibility and elasticity. As such, many users turn to TPU when printing flexible or shock-absorbing components such as rubber feet, Go-Pro stands and cable ties.

Although there are many brands of TPU filaments, one thing they have in common is their difficulty in printing compared to other printed materials. The natural flexibility and elasticity of the TPU make it difficult for the extruder to properly push the thread through the hot end without changing its diameter and causing clogging of the nozzles. This is usually a problem for printers that use a Bowden extruder, which "offers" more space to stretch the thread. Therefore, a direct drive system is preferred for this material.

While the main challenge for users printing TPUs is usually the extruder, there are other factors that also affect printing capabilities. The hot end temperature is probably the most critical setting controlled by slicer, for any material, especially TPU, which already has a fair share of extrusion problems. Bed temperature is also very important, as you do not want your TPU models to be deformed on the print bed.

In this article, we will look at the ideal temperature ranges for the hot end and the TPU printing bed. They can be used in your slicer profile to create the best prints. We will also discuss some of the bad signs to look out for when printing a TPU and how they may be related to your temperature settings. Let's dive into the topic!

Hot End: Ideal range

Good temperature of the TPU printing nozzles is 210 to 230 ° C (Source: 
Reza Rahmati via 3D Print 'Em)

Like any printed material, the TPU does not have the exact hot end temperature guaranteed to work for any spool of this material. However, you should be able to achieve high quality results with most TPU filaments using hot temperatures between 210 and 230 ° C.

The exact printing temperature will depend on the specific spool (eg brand, batch) TPU thread you have. Typically, more flexible threads, such as NinjaTek's NinjaFlex, require higher print temperatures (225-250 ° C) than less flexible options, such as Amazon Basic's TPU filament (210-230 ° C).

It is also always a good idea to check the temperature ranges suggested by the manufacturer of your particular thread reel, as they probably know the most about the specific TPU blend used to create the thread.

Hot End: Bad signs

Using too hot a temperature at the hot end causes insufficient extrusion of TPU prints (Source: x5titch via Reddit)

Of course, even if you use a temperature in our ideal range, you may still encounter temperature issues, as 3D printing materials are usually sensitive to temperature changes greater than 5 ° C. There are two main bad signs that can indicate whether you need to raise your temperature.

Insufficient extrusion

The first and perhaps most common bad sign you may experience when printing with TPU is insufficient extrusion. Small gaps in the impression, the clicking noise of the extruder, the grinding of the threads and the fragile impressions are bad signs of insufficient extrusion. This is probably due to the use of too low a nozzle temperature to melt the thread quickly enough and ensure proper adhesion from layer to layer. If this is the case, consider raising the temperature of the hot end.

Excessive extrusion

On the reverse side of insufficient extrusion, we have over-extrusion, which is a superfluous material when printing. String, spots, pimples and scars on your model are quite visible signs of excessive extrusion and too high a temperature setting. If you notice these problems, we suggest reducing the temperature of the hot end.

If any of these problems affect your prints and you need to adjust the hot edge temperature, we recommend that you do so in 5 ° C increments until the problem disappears. Any increase greater than 5 ° C can be overcompensating and cause other problems.

Heated bed: ideal range

Bed temperature between 30 and 60 ° C works great for TPU
(Source: turtlelore2 via Reddit)

While the temperature of the hot end affects the extrusion, the temperature of the heated layer affects the adhesion and can be adjusted to control how well the models, especially their first layer, adhere to the printed surface. Technically, TPU does not require a heated bed, but printing the material without one usually leads to distortion, so it is best to have a heated bed. The ideal temperature of the TPU printing bed is between 30 and 60 ° C - very close to that of the PLA.

As we explained earlier, there is no universal hot end temperature that applies to bed temperature. However, the temperature of the bed is not as sensitive as the temperature of the hot end, and you may not notice a difference in the prints, as long as you keep the minimum temperature to prevent distortion.

The main concern in finding the right bed temperature is the ambient temperature. If the room where your printer is located is cold, you should use a higher bed temperature. Alternatively, you can invest in a case that helps maintain the ambient temperature around the printer and prevents unwanted currents.

Heated bed: Bad signs

You can solve the "distortion" by increasing the temperature of the bed (Source: ronoaldo via Reddit)

When it comes to bed temperature, there are a few bad signs that you can detect and use to set your bed temperature on your TPU printer. The most obvious indicator of incorrect bed temperature is distortion, in which the areas of the footprint that come in contact with the building board do not stay down and rise (usually in the corners of the footprint). You can prevent fingerprint distortion by raising the temperature of the bed to help the first layer adhere more securely to the building board.

The opposite of distortion and another sign that the temperature of the bed needs to be regulated is a problem known as "elephant's foot". This is when the edges of the impression that touch the building board expand and protrude along the outline of the model, which is a form of over-extrusion. As you might expect, an elephant's foot can be eliminated by lowering the temperature of your bed.

Similar to the temperature of the hot end, we suggest making adjustments to the temperature of the bed in steps of 5 ° C. This will ensure that you do not over-correct your problem and accidentally cause the opposite of the problem you are trying to fix.

Other factors

Temperature towers help you find out which temperatures work and which don't (Source: CupOfJoe190 via Imgur)

When it comes to setting your printing temperatures, you should use test prints, as they can reveal a lot of information about your temperatures. The temperature tower test print is a quick way to assess the print quality of your machine at different temperatures without having to print a model for each temperature.

In addition to the settings for the hot end and the temperature of the bed, it is important to remember that with every 3D print there are many factors in the game. Everything from the weather outside and the air conditioning in your printer's room to the quality of the nozzle you use, and even the CPU speed of your motherboard, can affect print quality.

Even when the problem may seem to be related to temperature, it may not be. Problems such as a partially clogged nozzle, an uncalibrated extruder, and a damp thread can lead to low-quality prints similar to those that can occur when using poor temperatures. Be sure to consider other solutions if you have made significant temperature changes (eg using twice the recommended bed temperature) and do not see any changes in the prints.


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