Hot End - Extruder

I would like to open the following for discussion and standardizing. To standardize the definition and use of the terms: 'Hot End' and 'Extruder'.

Reason: The current use of Extruder when one is refering to the Hot End is inaccurate and confusing. In current use the term Extruder is switched back and forth between Extruder when refering to filament delivery rates and devices built or calibrated. Then, Extruder is also used in writing documentation when it is to be expressly refering to the Hot End. We have Direct Extruders and remote Bowden Extruders but, the Extruder is not heated nor should it be. That would be the Hot End.

Example: In the RepRap G-code page here The M104 & M105 Commands are directly referring to the 'Hot End' but, is written as to the 'Extruder'. Whereas the M113 is for the Extruder Stepper Motor. The Hot End does not have a Stepper. There are other occurances in this document as well as others throughout the RepRap site.


I'd like to propose that all references and definition to each, 'Extruder' & 'Hot End', should be standardized within documentation, specifications, designs, gcode descriptions, tutorials and such to mean - as follows:

Hot End: Defined as the Print device which contains the plastic heating method and print nozzle of the printer. [Or similar... You got the idea. ;-)]

Extruder: Plastic filament delivery device which transfers the plastic filament from a roll, spool or similar, to the Hot End for extrusion. [Or similar/like description.]

Comments?

I agree with you. This is especially true for a bowden fed / ultimaker style device since the Hot End and Extruder isn't even in the same assembly.

Yeah, I've heard that part of the printer called all sorts of things! Maybe we should invite suggestions from the forum readers...

Here's some:
*Filament pump. (hobbed bolt and gearing)
*Cooling chamber. (cold end)
*Heated injector. (Hot-end)

C'mon guys, give us your suggestions..

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Waitaki 3D Printer

How about: [reprap.org] ?

These are defined pretty well there. Just need an explicit definition for cold end.

Extruder:
A group of parts which handles feeding and extruding of the build material. Consists of two assemblies: a cold end to pull and feed the thermoplastic from the spool, and a hot end that melts and extrudes the thermoplastic.

Hot End:
The parts of the extruder that get hot enough to melt plastic, or potentially other materials. Hot end parts use materials that can stand up to ~240 °C heat (for current thermoplastic extrusion). The hot end usually refers to the tip of the extruder as it should be hottest there.

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