How Long Does It Take To Preheat a 3D Printer?

If you’re wondering how long it takes for a 3D printer to preheat before it can get into the action and work up your model, you aren’t alone. Preheating takes a bit of patience, but it is usually pretty quick and painless. 

It can take 2 to 5 minutes to preheat your printer, depending on the 3D printer and the materials to print. However, the preheating process may take even longer if you use a filament that requires a very high temperature, such as polycarbonate. 

Continue reading to learn more about why preheating is a critical step of 3D printing. I’ll also tell you what happens if you preheat your printer to the incorrect temperature and share some tips to help you find the ideal temperature range for your favorite filaments. 

Why Is It Important To Preheat a 3D Printer?

It is essential to preheat a 3D printer because the hotend must melt your filament properly before your print begins. It may take your printer a while to start extruding filament without preheating. Thus, if your printer preheats as it prints, it might skip the first few layers of the object. 

3D printers need time to warm up, just like a conventional oven. 

To better understand why preheating is so critical for a quality print, let’s imagine that you skipped the preheat and went straight into your first layer with a cold 3D printer. 

In that case, your printer would push filament into the hotend, but the filament would not melt. As it pushed, it would start moving the print head around to create your first layer, but nothing would come out for about five minutes. 

Thus, without preheating, your printer would “print” the first few layers without extruding any filament, skewing the dimensions and layers in your object. 

How Warm Should Your 3D Printer Be After Preheating?

Preheating ensures that the filament the printer can do a quick and efficient job printing the filament once you insert it, and in most cases, your printer will not let you start a print unless you preheat the machine. 

Your printer should be warm enough to liquefy your filament after preheating. The ideal temperature will vary depending on your material, as each thermoplastic has a unique print temperature. Likewise, heated print beds must preheat so your print stays sticky during the printing process. 

Maintaining the correct temperature during preheating and printing is vital to producing a stable final object. 

Let’s examine the consequences of preheating and printing at the wrong temperature. 

What Happens if the Preheating Temperature Is Wrong?

Preheating a 3D printer at the correct temperature ensures the filament melts down to the right consistency at a steady rate, which allows it to print the molten filament in smooth, consistent layers. 

With the wrong temperature, you can’t expect things to go smoothly at all. 

Setting The Hotend Temperature Too High Causes Over-Extrusion

If your filament’s printing temperature is wrong, the print will likely look poor or fail. 

Overheating spells terrible news for technical prints, especially as droopy filament won’t be able to form precise shapes and exact designs. Instead, the object may melt or collapse in on itself – picture a fresh grilled-cheese sandwich. 

An overheated nozzle may also result in globby, lumpy, over-extruded filament, which is hard, if not impossible, to remove once solidified. 

Likewise, overheating your filament can create clogs inside the hotend, which requires special cleaning and purging processes to remove.

Underheating Results In Clogs and Under-Extrusion

Underheating is just as bad as overheating. A too-cool extruder can cause jams, under-extrusion, and delamination. 

Clogs and under-extrusion can also strain your printer’s stepper motors. In the worst cases, it can even strip the gears in your extruder. 

Plus, the prints will not have proper layer adhesion, resulting in objects that aren’t going to stand up to any pressure. 

Under and Over-Heating Print Beds Result in Warping or Adhesion Issues

While the risks of overheating your hotend are bad enough, setting your print bed temperature too high or low also comes with unwanted side effects. 

Preheating a print bed allows the filament to adhere better, creating a more stable base for the rest of the print.

The print bed needs to be at a specific temperature when the print is in progress to allow it to cool slowly and maintain its structural integrity. If the surface is too cool, the object will cool too rapidly, and it may slide off the bed mid-print.

 If it’s too hot, an issue called elephant’s foot occurs.

Elephant’s foot refers to when the first few layers of the print melt and compress under the weight of the layers above them. 

Maker’s Muse illustrates what elephant’s foot is and how to tweak your printer setting to prevent it from happening. 

The Correct Preheating Temperatures for Your Filament

Every printing material requires a different preheat and print temperature for your printer to extrude it properly. 

Below is a table comparing popular 3D printing materials and their ideal temperatures. 

Material	Temperature
ABS	446 to 464°F (230 – 240°C)
PVA	374 to 428°F (190 – 220°C)
Nylon	464 to 536°F (240 – 280°C)
Polycarbonate	482 to 608°F (250 – 320°C)
PETG	446 to 482°F (230 – 250°C)
PolyFlex	410 to 464°F (210 – 240°C)

Looking over this table, you’ll see the Polycarbonate (PC) filament requires the highest temperatures. PVA requires the lowest temperature and is moisture-sensitive, soft, and biodegradable.

When using any material, you can experiment with different printing temperatures and find what works best for you and your particular filament. 

Testing new temperatures can help you stop lousy adhesion and melting before it even happens.

However – and I cannot repeat this enough – you should always use a temperature within the range specified on your particular filament spool. 

Watch the following video by Vision miner to learn more about the relationship between temperature and filaments of different materials. 

How To Fix a Blocked or Clogged Nozzle

A blocked nozzle means no printing. If left unattended, it can even damage the nozzle long-term. Identifying why the nozzle is blocked is the first step to fixing the issue. 

Some of the most common causes of jams include:

• If you do not keep the hotend warm during printing, the filament will form a plug in the nozzle, stopping anything from coming out. 
• Not cleaning the nozzle can lead to a filament build-up.
• Dust, dirty filament, and oily residue can mess with the nozzle and weaken its performance, ultimately causing blockages. 

A blocked nozzle is bad news for any printer, but the fix is pretty simple.

You can use several methods to clean out any clogs:

• Purging. For minor clogs, preheating your printer may be enough to melt and extrude any leftover clumps of plastic. 
• Brass wire brush: Use a brass wire brush to remove any residue from the nozzle. Ensure you don’t use a steel wire brush, which could damage the nozzle. 
• Needle: Heat the nozzle, and move the needle inside it to clear any residue and sticky filament that may have been left behind from a previous print. 
• Remove the nozzle: Using a wrench, unscrew the nozzle and place it in a chemical solution to melt off the leftover filament. Alternatively, use a hairdryer or heat gun to melt away any residue. 

Note that the chemical solution you should use to dissolve filament residue depends on the material used to print. ABS is easily dissolvable in acetone, but acetone doesn’t affect nylon filaments. 

Conclusion

Every filament prints best when you preheat your 3D printer, but each material requires a unique temperature for the best results. If you preheat your printer outside the ideal range for your material, you could experience one of many issues. 

Research and experimentation are the best ways to determine what temperature to use. Remember to clean your equipment regularly and use the correct settings to ensure it stays in good condition.