• 3D Printing
  • 3d printing and extrusion is not a cause, what should I do?

In order for a 3D printer to produce accurate parts, it is necessary to be able to extrude a very consistent amount of plastic. If the extrusion changes during the printing process, it will definitely affect the final print quality. Extrusion inconsistencies can usually be found by looking at your printer at close range while it is working. For example, if the 3D printer is printing a 20mm long straight line, but you find that the extruded part is quite uneven or the size is changing, it is probably the problem. We summarize some of the most common causes of extrusion inconsistency and explain how each is positioned.

Consumables stuck or tangled: The first thing to check is the tray that is being fed. Make sure the consumable tray is free to rotate and the consumables can be easily unwound from the disc. If the consumables are knotted or the resistance of the consumable plate is too large, it will affect the smooth extrusion of the consumables. If the printer uses a distal extrusion, check the resistance inside the wire feed tube. If the resistance is too great, please clean the wire feeder or take some lubrication measures.

The extruder is blocked: If the consumables are not knotted and can be easily pulled into the extruder, the next one to check is the nozzle itself. It is possible that any debris or other plastic is stuck in the nozzle, which affects normal extrusion. A simple check is to manually squeeze out some of the material using Simplify3D's machine control panel. Observe whether the extrusion is smooth and consistent. Once you find the problem, you need to clean the nozzle. Consult the printer manufacturer for proper cleaning instructions for the inside of the nozzle.

The floor height is too low: If the consumables rotate freely and the extruder is not blocked, it may be useful to check some settings. For example, some of you try to print at very low floor heights, like 0.01mm, where the plastic is particularly small when it leaves the nozzle. The gap below the nozzle is only 0.01 mm high, which means that the plastic leaves the extruder. It is reasonable to repeatedly confirm that the layer height you are using is good for your printer. Modify the value of the "Layer" of the "Basic" page. If you are using a very low layer height, increase the layer height to see if the problem disappears.

Wrong extrusion width: If you use Simplify3D, the other thing you need to check is the extrusion width. Click on "Edit Process Settings" to go to the Extruder tab to find this setting. Each extruder has its corresponding extrusion width, so select the correct extruder from the list on the left to see the corresponding setup parameters. If the extrusion width is significantly smaller than the diameter of the nozzle, it will cause extrusion problems. As a rule of thumb, the extrusion width should be 100-150% of the diameter of the nozzle. If the extrusion width is too low (for example, a 0.4 mm nozzle uses an extrusion width of 0.2 mm), it will not be possible for the extruder to push the consumables consistently. Poor quality of consumables: There is also a common cause of inconsistent extrusion. What we have not mentioned is the quality of the consumables being used. Poor quality supplies may contain additional ingredients that affect the consistency of the plastic. There are also some consumables that may have inconsistent diameters and can cause inconsistent extrusion. Finally, most plastics degrade due to long periods of time. For example, PLA absorbs moisture from the air for a long time, which can result in poor print quality. This is why many consumable reels contain a desiccant to aid in the removal of moisture. If you feel that the consumables are broken, it is better to have a new unopened high-quality consumables and see if the problem disappears. Extruder mechanical problems: If you have checked all of the above problems, or if the extrusion is inconsistent, then you need to check the mechanical problems of the extruder. For example, many extruders use a sharp wire feed wheel to bite the consumables. Thereby the extruder can freely drive the consumables back and forth. These extruders also generally have an adjustment mechanism that can change the pressure of the wire feed wheel to the consumables. If this pressure setting is too loose, the feed wheel will not be fed deep enough, which will affect the extruder's ability to precisely control the position of the consumables. Check with your printer manufacturer to see if your printer has a similar adjustment mechanism.