Nozzle plays the most difficult part, which we could biblically define the passage of the camel through the eye of a needle. That is, the deposit of the molten plastic is the nozzle.
You can find a lot of nozzles, with a lot of differences.
The difference that immediately catches the eye is the size of the exit hole of the material. There are many different sizes, mainly ranging from 0.2 mm to 0.8 mm, depending on the type of print to be dealt with.
An artistic print, very small and with many details we will prefer to print it with an exit hole of 0.3 mm. A coarse piece, maybe cubic, we can use larger nozzles reducing the execution time.
Normally on commercial printers is installed by default a nozzle of 0.4 mm. This because it allows you to print many details, rather quickly. At the same time, it avoids some problems that can be encountered if you go down with the measures.
This component is one of the most problematic. If you make a mistake it is very easy to shut it down and in any case must be cleaned and checked regularly. We have dedicated an article to the cleaning of the nozzle and we propose it to you at this link.
Nozzle could also made of different materials.
The typical one is made of brass but this material is easily abraded. Especially by filaments loaded with metals or carbon. To overcome this problem you can opt for a steel one, much more resistant to abrasion. Or maybe you could use hardened steel or even more resistant.
If you want to completely eliminate the problem of abrasion, you can opt for a nozzle made with a ruby. Even if it costs hundreds of times as much as a normal nozzles. It probably costs as much as your printer!
Hardened Steel Nozzle:
Ruby Nozzle (a real ruby):
Nozzle: something to consider
A measure to consider when talking about nozzle replacement is the ratio between the threaded part and the external part, in fact, the replacement of the final part is likely to correspond with the revision of the endstops of the Z axis or the offset of the level probe of the plate.
Nozzles can be found in all major e-commerce, and we recommend that you buy a few in reserve, as they are consumable material and generally very cheap:
Look on Aliexpress