There are 4 reasons for the problem:

1. No consumables in the nozzle before printing

A: Most extruders will hover at high temperatures and the melted consumables in the nozzle flow out on their own, this often results in the nozzle running dry of consumables and creating an empty cavity. This leads to a situation where the extruder needs to wait a few seconds before discharging the material when extruding; a situation where the print just starts without discharging the material. The core of the solution to this problem is to ensure that there is sufficient melted consumables in the nozzle before starting to print. The most common solution is to add a skirt, add a few circles of the skirt will be before the official start of the print object, in the periphery of the object to draw a few circles, so that the nozzle has enough melted consumables.

2. The nozzle is too close to the platform at the start of the print run.

A: There is not enough room for the melted consumables to flow out. In this case, the consumables usually do not flow out until the 3rd or 4th layer of the print. Try leveling, adjusting the height of the first layer of the slicing software, or adding a Z-axis offset.

3. The consumable has been bitten off by the extrusion wheel and has lost its grip.

A: Consumables rejection. Reduce the damaged consumables and reload the consumables.

4. Printhead clogging

A: If none of the above solutions have solved your problem, then it is likely because the printhead is clogged with magazines. Unclogging the nozzle will most likely require disassembling the extruder. You need to consult with the manufacturer before disassembling to prevent loss of warranty. Tools for unclogging the nozzle: choose the right tool for the diameter of the nozzle, drill, acupuncture needle, guitar E-string.