Since its introduction in the 1980s, 3D printing or additive manufacturing has been a popular means of creating prototypes and custom consumer goods. This manufacturing technique has many variations but the most widely used among them is Fused Deposition Modeling or FDM 3D printing.

These printers use thermoplastic filament that is heated to its melting point and then added layer by layer until it creates a three-dimensional part or product. The parts created by FDM 3D printers are rigid, which makes them perfect for projects with this requirements.

Like any other method, there are also problems that you may encounter when using FDM 3D printing. In this article, we are going to explore some of the most common problems encountered while using these printers and how you can prevent them.

How Does FDM 3D Printing Work?

In FDM 3D printing, the product starts as a computer-aided design (CAD) file. Before printing, this file is converted to STL format, which is compatible with the 3D printer.

During the process, the plastic threads or filaments are fed through an extrusion nozzle. Here, it melts and extrudes into a base or a platform. The nozzle and the base are both controlled by the computer and translate the dimensions of the object into X, Y, Z axes.

Typically, the nozzle moves over the platform in a horizontal and vertical motion to draw the cross-section of the object. As the thin layer of plastic cools and hardens, it immediately binds to the layer beneath it. Once this is completed the platform is lowered to repeat the process.

Common Problems in FDM 3D Printing

The FDM 3D printer needs to be well-calibrated and run by an experienced operator to avoid any printing problem.

Warping

You can easily identify warping as it is visible with the corners of the bottom part bent upwards. This problem is caused by factors. First is the lack of adhesion to the bed and second is the thermal contraction of the upper layers.

The first is due to the excessive distance of the nozzle from the base or poor leveling causing insufficient adhesion. Thermal contraction, meanwhile, is common among ABS and nylon material when shrinking.

Cracking

Cracking happens when the layers of the material are not joined properly. It can be due to the poor adhesion of the layers because of low printing temperature. Another reason is due to thermal shrinkage. The difference in temperature between the layers is what's causing it to crack and the layers to separate.

Shifting of Layers

Shifting happens when there is a displacement of the material on some axis at a different height. It can be caused by any of the following: excessive temperature in the drivers, the lack of power in the drivers, and a mechanical failure.

Z-Wobble

The problem is commonly due to the structural failures of the machine. This could be difficult to solve, and you have to check if the parts are properly assembled, and there are no loose screws. You can also tighten the components of the Z-axis to make sure that there is no wobble.

Stringing

This problem happens when as the hot end moves between the sections of the print, an amount of plastic drips off and sticks on the sections leaving a trail of small thread. This problem is caused by inaccurate temperature settings during the slicing process. Check the temperature, retraction distance, and retraction speed.

There you have it. The most common problems when using FDM 3D printers. Bear these problems in mind to ensure that there are no snags on your project.