Stainless steel nozzle
BRASS NOZZLE
I am not against brass nozzles but lets face facts. I started printing with a standard brass nozzle. But the more i use, the more maintenance it needed.
Major issues were;
Messy Nozzle
fast wear and tear
leaking PLA through threads
Blobs sticking to nozzle which later gets deposited on print surface etc
Cheap brass nozzles contains high traces lead which is toxic and carcinogenic but the lead content is lower for any immediate effects.
No proper material datasheets attached with the brass nozzles.
The prints contain micro amounts of lead which is toxic to health an environment.
So i switched to stainless steel nozzle.
Stainless Steel nozzle
Advantages :
Stainless steel is medical grade and FDA approved, means the prints are food grade.
Less Maintenance required as the molten plastic wont stick to the steel.
Smooth flow for the above mentioned property
Almost no wear and tear on PLA printing.
Disadvantages :
Requires more heat, typically 20-30C Above brass nozzle temperature
Stainless steel nozzles are expensive
note :
sometimes we use a magnet to test if the nozzle is stainless steel. But not in all cases its true as grade 304 Austenitic Stainless Steel contains nickel, chromium, and carbon are non magnetic.
The food industry uses SS 304 mostly and recent studies shows that Stainless steel can leech chromium and nickel into food while cooking. (read)
As per ncbi, stainless steel leaches nickel and chromium into foods during cooking and the same could happen to printed parts as we are extruding molten plastic through a stainless steel nozzle. But i do prefer stainless steel over leaded brass nozzles.
Mild Steel Nozzle
Mild and low carbon steel nozzles are the next in the series. It is composed of Carbon, manganese, Silicon and traces of other elements such as phosphorous, lead or sulphur
Advantages :
High heat transfer than Stainless steel nozzles.
Less maintenance
Disadvantages :
Lead is toxic and a threat to environment
PRINT QUALITY ANALYSIS : Brass vs Stainless
From all the above materials, Id select Stainless steel 304 as the preferred nozzle as it is the material majorly used by the food industry and in medical applications.
Since 2021, All the prints are done with a 0.4 mm stainless steel nozzle and the print quality is even better than any standard brass nozzles.
The left vase is printed with stainless steel nozzle and the right is printed with brass nozzle. The settings except temperature values are same.
From my review, The stainless steel print got better layer quality than brass print. It is probably due to the efficient flow and non sticking property of the 304 nozzle.
One of the best print i have ever achieved and that's definetly with the stainless steel nozzle.