It is unnerving to find a plastic blob on the hot end of your 3D printer, and it should be, because it can damage the printer if you're not careful! Here's how you can get your printer back into printing condition and fix the issue long term.
To remove the plastic blob safely, follow these steps:
- Heat the hot end to the printing temperature of the filament material that is stuck on your hot end.
- Use a pair of pliers to gently remove the plastic blob from the hot end. Be careful not to pull hard on the thermistor, heater, or other wiring that penetrates through the plastic blob. Do not use excessive force, because it could damage your 3D printer. You may need to give the heat time to soak completely through the plastic blob, so that it softens as much as possible to minimize risk to your printer’s hot end.
- After the plastic blob is removed, clean the heated block, nozzle, and other parts that the blob was in contact with.
The primary cause of plastic blobs is a small gap that allows plastic to ooze either between the nozzle and the heated block, or the heated block and the heat break. To prevent this from happening in the future, you can take the following steps:
- Heat the heated block to the 3D printer filament’s printing temperature.
- Grab the heated block with one set of pliers and the nozzle with another set of pliers.
- Tighten the nozzle to the heated block by steadily and slowly increasing torque on the nozzle to tighten it until increasing torque further doesn’t cause it to move more. Too much torque/force can shear threads or break something, so be careful.
- Avoid printing at temperatures higher than recommended for your filament. Excessively high temperatures can cause the threads to loosen and allow oozing again.
Plastic blobs can also be caused by a print getting stuck to the hot end. You need to ensure the best possible bed adhesion to prevent prints from coming off the bed. Fortunately, we cover that in this post.
By taking these steps, you can fix plastic blobs on your hot end and prevent plastic blobs from forming in the future. This will help ensure that your prints come out beautifully. If you have any other tips or questions, please leave them in the comments below!