A bad 3D print looks like a distorted, incomplete, or low-quality version of the intended design. It can have various defects such as warping, stringing, layer shifting, under-extrusion, over-extrusion, blobs, zits, cracks, gaps, or poor surface finish. A bad 3D print can result from improper settings, faulty hardware, incorrect materials, or human errors. In this article, we will explore some of the common causes and solutions for bad 3D prints, as well as some tips on how to prevent them in the first place.
Warping is one of the most common issues that affect 3D prints. It occurs when the edges or corners of the print curl up or lift off the build plate, causing the print to lose its shape and dimensions. Warping is usually caused by uneven cooling of the print, which creates internal stresses and forces the material to contract. Warping can also be influenced by the ambient temperature, the bed temperature, the nozzle temperature, the print speed, the fan speed, the material type, and the bed adhesion.
To prevent warping, you should try to maintain a consistent temperature throughout the printing process, and avoid exposing the print to drafts or sudden changes in the environment. You should also use a heated bed and a suitable bed surface that matches the material you are using. For example, PLA works well with blue painter’s tape, ABS works well with kapton tape or hairspray, and PETG works well with PEI sheets or glue stick. You should also adjust the nozzle temperature, the print speed, the fan speed, and the layer height according to the material specifications and the print quality you want to achieve. Additionally, you can use a brim, a raft, or a skirt to increase the bed adhesion and stability of the print.
Stringing is another common problem that affects 3D prints. It occurs when thin strands of filament ooze out of the nozzle and form strings or hairs between different parts of the print. Stringing can ruin the appearance and functionality of the print, especially if it involves intricate details or moving parts. Stringing is usually caused by excessive nozzle temperature, insufficient retraction, fast travel speed, or low-quality filament.
To prevent stringing, you should lower the nozzle temperature to the minimum required for the material you are using, and increase the retraction distance and speed to reduce the pressure inside the nozzle. You should also lower the travel speed to give the filament more time to cool down and solidify before moving to the next position. Moreover, you should use high-quality filament that has consistent diameter and moisture content, and store it in a dry and cool place to avoid degradation.
Layer Shifting
Layer shifting is another issue that can affect 3D prints. It occurs when the layers of the print do not align properly, creating a staircase or zigzag effect. Layer shifting can compromise the accuracy and strength of the print, and make it look unprofessional and sloppy. Layer shifting is usually caused by loose belts, pulleys, or screws, misaligned or dirty rods, rails, or bearings, faulty stepper motors or drivers, or incorrect acceleration or jerk settings.
To prevent layer shifting, you should check and tighten the belts, pulleys, and screws that connect the moving parts of the printer, and make sure they are not too loose or too tight. You should also clean and lubricate the rods, rails, and bearings that guide the movement of the printer, and make sure they are not bent, worn out, or obstructed by debris. Furthermore, you should inspect and replace the stepper motors or drivers that control the movement of the printer, and make sure they are not overheating, skipping steps, or losing power. Additionally, you should adjust the acceleration and jerk settings to match the capabilities of your printer and the quality of your print.
Under-extrusion and over-extrusion are two opposite issues that can affect 3D prints. Under-extrusion occurs when the printer extrudes less filament than needed, resulting in thin, weak, or missing layers. Over-extrusion occurs when the printer extrudes more filament than needed, resulting in thick, blobby, or overlapping layers. Both issues can affect the appearance, accuracy, and durability of the print, and cause other problems such as clogging, stringing, or warping. Under-extrusion and over-extrusion are usually caused by incorrect extrusion multiplier, flow rate, or filament diameter settings, clogged or worn out nozzle, tangled or jammed filament, or inconsistent or low-quality filament.
To prevent under-extrusion and over-extrusion, you should calibrate the extrusion multiplier, flow rate, and filament diameter settings to match the actual characteristics of your printer and filament. You should also clean and replace the nozzle regularly, and make sure it is not blocked by dirt or debris. Moreover, you should use a spool holder or a filament guide to prevent the filament from tangling or jamming, and use high-quality filament that has consistent diameter and moisture content.
Blobs, Zits, Cracks, Gaps, and Poor Surface Finish
Blobs, zits, cracks, gaps, and poor surface finish are some of the other issues that can affect 3D prints. Blobs and zits are small bumps or protrusions that appear on the surface of the print, usually at the start or end of a layer or a perimeter. Cracks are fissures or splits that appear on the print, usually along the layer lines or the infill. Gaps are holes or spaces that appear on the print, usually between the layers, the perimeters, or the infill. Poor surface finish is a general term that describes the roughness, unevenness, or irregularity of the print surface. These issues can affect the aesthetics and functionality of the print, and make it look unappealing and defective. These issues can be caused by various factors such as incorrect temperature, speed, cooling, retraction, coasting, or z-hop settings, insufficient or excessive infill, incorrect layer height or width, or improper post-processing.
To prevent these issues, you should fine-tune the temperature, speed, cooling, retraction, coasting, and z-hop settings to optimize the extrusion and movement of the printer. You should also choose the appropriate infill percentage, pattern, and density to provide enough support and strength for the print. Moreover, you should select the optimal layer height and width to balance the print quality and speed. Furthermore, you should use proper post-processing techniques such as sanding, smoothing, painting, or coating to improve the appearance and durability of the print.
Conclusion
3D printing is a fascinating and rewarding technology that can create amazing objects and models. However, it is not without its challenges and difficulties. Sometimes, 3D prints can turn out bad, due to various factors such as improper settings, faulty hardware, incorrect materials, or human errors. In this article, we have discussed some of the common causes and solutions for bad 3D prints, as well as some tips on how to prevent them in the first place. By following these guidelines, you can improve your 3D printing skills and experience, and achieve better results. Happy printing!
