# Worn Nozzle

![Image from MakeZine](https://1820679795-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LXautSvCbUco5Lv7YrH%2F-MS_EyVkNjSB6KBJ7R_s%2F-MS_GxABMLdGHNCYDmAW%2Fimage.png?alt=media\&token=6a28919d-5f8c-47cb-997d-dcbcdf01f76a)

Nozzle wear occurs when the diameter of the orifice becomes wider (in this case, >0.4mm) or no longer becomes round. These typically happen on brass nozzles and are caused when abrasive filaments such as carbon fills, wood fills and metal fills are used. A worn nozzle leads to unpredictable extrusion and print finishes as the extrusion is based off a round orifice with a set diameter of 1.75mm.

**When is it a good time to change your nozzle? Read more about it here:**

{% embed url="<https://3dprinterly.com/when-how-often-should-you-change-your-nozzle-on-your-3d-printer/>" %}


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