8 Tips and Tricks for Printing With Old Filament

Printing with a 3D printer is a fun and rewarding experience, but it can also be expensive. In some cases, you may need to use an old filament to reduce costs, especially when working on basic prototypes or small projects. While it is possible to print with old filament, there are a few tips and tricks to ensure quality prints and avoid damage to your printer.

Here are 8 tips and tricks for printing with old filament:

1. Check the spool for damage before printing.
2. Dry the filament.
3. Clean your printer using isopropyl alcohol.
4. Don’t use too much force when loading the filament
5. Print at the recommended temperature.
6. Monitor the print quality during the print job.
7. Use a brim to help prints stick to the build plate.
8. Store leftover filament in a cool, dry place.

Are you having trouble printing with your old filament? Don’t worry– you’re not alone! Read on for a rundown of these tips and tricks to help make your prints look great, even if your filament is old and expired. 

1. Check the Spool for Damage Before Printing

Before you use an old filament, you should first check the spool for any damage. Damage spots can cause problems during printing and even harm your printer.

Here are a few things to look for when checking the spool:

• Cracked or broken filament
• Discoloration or warping
• Dust or debris

If you find any damage, do not print with the filament. Instead, contact the manufacturer or check online e-commerce platforms, such as Amazon.com, for a replacement.

However, if the spool looks okay, you likely won’t have any issues using it. Still, you’ll need to prepare the filament before feeding it in. 

2. Dry the Filament

One of the problems with using old filament is that it can be damp. Moisture in your filament can cause problems with the printing process, such as poor quality prints and even damage to your printer.

The common signs of wet filament include:

• The filament is swollen with a wider diameter.
• The filament creates weak prints with poor layer adhesion.
• The filament pops or cracks during extrusion.
• It creates highly textured surfaces.

One way to reduce the chances of these problems is to dry the filament before you use it. The best way to do this is by using a filament dryer. If you don’t have a filament dryer, you can also use an oven.

Here’s how to dry old filament using an oven:

1. Preheat your oven to the right temperature for your filament material. The table below should guide you on the appropriate temperature for each filament type.
2. Using a glass thermometer, check the oven’s temperature to see if the internal temperature is correct. If not, wait for the oven to heat up before continuing.
3. Once the oven has reached the right temperature, carefully place the filament spool on your oven’s wire rack.
4. Leave the filament in the oven for 4-10 hours, or until it is dry. Again, the table below should help you determine the correct drying time for your filament.
5. After the filament is dry, remove it from the oven and let it cool to room temperature before using it.

Filament Material	Recommended Oven Temperature	Recommended Heating Time
Poly Lactic Acid (PLA)	104°F – 122°F (40°C – 50°C)	4-6 hours
Acrylonitrile Butadiene Styrene (ABS)	149°F – 167°F (65°C – 75°C)	4-6 hours
Polyethylene Terephthalate (PET)	140°F – 149°F (60°C – 65°C)	4-6 hours
Ninjaflex & Thermoplastic Urethane (TPU)	104°F – 113°F (40°C – 45°C)	4-5 hours
Nylon	167°F – 374°F (75°C – 90°C)	4-6 hours

3. Clean Your Printer Using Isopropyl Alcohol

One of the best ways to ensure quality prints with old filament is to clean your printer using isopropyl alcohol. A good wipe-down will help remove any debris or dust that may have built up over time.

Here’s how to clean your printer using isopropyl alcohol:

1. Turn off your printer and unplug it from the power outlet.
2. Ensure the build plate is cool to the touch before removing any prints.
3. Using a lint-free cloth or paper towel, wipe down the entire surface of the printer. Be sure to pay special attention to the extruder, nozzle, and build plate.
4. If there is any debris or dust inside the printer, use a can of compressed air to clean it out.

Caution: Be very careful when using isopropyl alcohol since it is flammable. Do not smoke or use an open flame near the printer while cleaning it.

4. Don’t Use Too Much Force When Loading the Filament

When loading old filament into your printer, be sure not to use too much force. Applying force can cause damage to the filament and may even jam the printer, especially if your filament is older and more brittle than when you unboxed it.

Here’s how to load filament without using too much force:

1. Open the lid of the printer’s extruder.
2. Gently insert the filament into the extruder.
3. Make sure you align the filament with the extruder’s drive gear.
4. Clamp the filament in place using the clamping arm.

Here’s a demo of how to load the old filament into your printer without breaking it:

5. Print at the Recommended Temperature

It’s vital to print at the recommended temperature when using old filament. Printing at the wrong temperature can cause poor-quality prints and damage your printer.

The table below provides the recommended printing temperatures for various filament types:

Filament Material	Recommended Printing Temperature
Poly Lactic Acid (PLA)	419°F – 455°F (215°C – 235°C)
Acrylonitrile Butadiene Styrene (ABS)	446°F – 464°F (230°C – 240°C)
Polyethylene Terephthalate (PET)	446°F – 482°F (230°C – 250°C)
Ninjaflex & Thermoplastic Urethane (TPU)	383°F – 446°F (195°C – 230°C)
Nylon	464°F – 536°F (240°C – 280°C)

6. Monitor the Print Quality During The Print Job

It’s also essential to monitor the print quality throughout the printing process. Keeping an eye on your printer will help you catch any problems early on and avoid ruining your prints.

Here are some tips for monitoring the print quality:

• Look for any gaps in the layers. If you spot any gaps, the chances are that you are using the wrong settings, the nozzle is clogged, the filament is too old, or the printer has mechanical issues that you must address.
• Check if the filament is sticking to the build plate. If not, you may need to adjust the bed adhesion or increase the printing temperature.
• Watch out for any signs of filament wobble. Wobbling can signify that the printer is not extruding enough filament or a problem with the hobbed bolt (the gear that grabs the filament and pushes it into the hot end).
• Watch for any strange shapes or defects in the prints. Odd artifacts, spaghetti-prints, or blobs can signify many printer problems, such as clogged nozzles, incorrect temperature settings, or too old filament.

7. Use a Brim To Help Prints Stick to the Build Plate

When printing with old filament, it’s good to use a brim. A brim will help the print stick to the build plate and reduce the chances of it coming off during the printing process.

The procedure for using brims varies with slicers, but the general idea is to add an extra layer of filament around the part that is supposed to stick to the build plate. For example, if you use Slic3r, you must follow these steps to add brims:

1. Open the Slic3r program.
2. Click the “File” menu on the top left corner and select “Preferences.”
3. From the pop-up menu, select “Expert” mode.
4. Exit the program, then reopen it.
5. Click the “Print Settings” Menu.
6. Click “skirt and brim.”
7. Modify the brim settings (a length of 250 mm and a width of 10-20 mm usually works well).

Now, when you print your model, Slic3r will add a brim around it to help it stick to the build plate.

Here’s an excellent tutorial on using brims in Slic3r:

8. Store Leftover Filament in a Cool, Dry Place

Once you’re done printing with the old filament, be sure to store the leftover filament in a cool, dry place. Proper storage will help keep it from becoming brittle and unusable.

Here are some tips for storing filament:

• Store the filament in a moisture-free environment.
• Keep the filament away from direct sunlight.
• Store the filament in a cool, dry place.
• You can store the filament in the original packaging or an airtight container.

Here’s a video tutorial of a few filament storage ideas you may find helpful: