Diagram of a 3D Printer

The image below is a printer in a Cartesian setup, where the build plate moves back and forth in the Y direction and the hotend left and right in the X direction – similar to the popular Bambu Lab A1, Creality Ender 3, and Prusa MK4 printers.

Diagram of a bed slinger printer

1. Z Carriage: This connects to both the Z rod and threaded rod/leadscrew. The leadscrew then turns due to the stepper motor it is attached to, which then moves the x carriage up and down. On Bowden machines this is often where the extruder is attached.

2. X Endstop: This is what tells the hotend to stop when homing. There is also a Y and Z endstop not shown in this picture which have the same function (though a Z endstop may be replaced by an auto bed leveler).

3. Build plate: This can be either glass, PEI, or another form of build plate. This is where the prints stick to.

4. Nozzle: Filament is fed through a heated nozzle in order to form your print. These can be found with different diameter holes, with the smaller the hole, the finer the detail. Nozzles range from 0.15mm – 1.2mm in diameter (sometimes thicker with hotends such as the SuperVolcano). They also come in brass, hardened steel, and ruby tip, with each becoming more abrasive resistant and more expensive.

5. X Carriage: This is where the hotend (and printers with direct extruders) attach to. The X carriage is attached to the X rods and belt which then in turn move the hotend in the X direction. This carriage should be very secured and not have any rattling.

6. Extruder: This is how the filament is fed into the nozzle. In this example we are showing a non-geared direct extruder. A geared extruder will have a gear-ratio allowing for less stress to be placed on the stepper motor, adding a mechanical advantage for more torque, allowing the filament to be fed faster. The extruder includes a tooth drive attached to the stepper motor that pinches the filament against a bearing that freely spins. There are dual drive extruders as well which replace this bearing with another tooth drive. This extruder can also be placed on the Z carriage in a Bowden fashion.

7. Extruder Stepper Motor: The extruder stepper is what turns and feeds filament through the extruder. This would be placed on the Z carriage when on a Bowden setup. This is what you are controlling when you set the E-Steps. When using a geared-extruder, you put less strain on this stepper motor by giving it a mechanical advantage, which would result in less extruder motor skips and a higher E-Step value. It would be smart to place a heat sink on this in order to disperse heat if you built your printer. This added weight when setup in a direct fashion can be one reason someone would prefer Bowden.

8. X Carriage Belt: This is what is connected to the X carriage as to move it left and right in the X direction via a stepper motor. This belt should be tight/springy to the touch as to reduce Z-wobble.

9. Y Stepper Motor: This stepper motor moves the bed back and forth in the Y direction by controlling the Y carriage belt. This is only present in this fashion on Cartesian machines. Remember on CoreXY setups, there is no “Y stepper Motor” as each motor moves both the X and Y axis dependent on one another.

10. Y Carriage Belt: This is the belt that is connected to the build plate and is controlled by the Y stepper motor and spins freely attached to a bearing on the other side. Just as with the X carriage belt, this should be tight and springy to the touch.

11. Y Smooth Rods: These rods are what the Y carriage are attached to via bearings and are smooth to the touch. They help to make sure the build plate moves smoothly back and forth without rattling. These rods should be lubricated with white lithium grease so that the build plate can move without resistance. These can be replaced with a rail system or aluminum extrusion with rollers instead on particular machines.

12. Active Cooling Fan: This fan is used to cool prints as layers are being laid down. This is crucial to use to get clean prints with particular materials, including PLA. This can lead to decreased layer adhesion on other particular materials, so you need to confirm the material you are using before turning it on in your slicer settings.

13. Z Stepper Motor: On some machines there is only one Z stepper motor, but there are dual steppers in this example. This stepper motor turns the Z leadscrew (or thin threaded rod) and moves the X and Z Carriage up and down, via where it is connected to the Z carriage (1 in photo). This is different on CoreXY machines, since those move the build plate up and down instead of the hotend.

14. Heaterblock of Hotend: This is the part of the hotend that gets hot and is attached to the heater. This is attached to the nozzle below it, and the barrel above it (with a heatbreak in between). The barrel should always have a fan blowing on it to prevent heat creep, though one is not shown in this picture.

15. X Smooth Rods: These rods are what the X carriage via bearings and are smooth to the touch. They help to make sure the hotend move smoothly left and right without rattling. These rods should be lubricated with white lithium grease so that the carriage can move without resistance. These can be replaced with a rail system or aluminum extrusion with rollers on particular machines.

16. Z Smooth Rods: There may only be one of these on your machine, but in the photo above, there are two Z smooth rods. These are what your Z carriage is attached via bearings to in order to ensure the Z carriages are moved up and down smoothly without rattling. They should remain lubricated just like the X and Y smooth rods as to ensure there is as little friction with the bearings as possible. These can also be replaced with a rail system or aluminum extrusion with rollers on particular machines.

17. Z Leadscrew (or threaded rod): These are threaded rods ranging from 5mm-10mm in diameter, with 8mm seeming to be the most common. Many machines only have one of these, but I have found when there are dual leadscrews you get more consistent results. These are turned via the Z stepper motors which then thread into the Z carriages – moving the Z and X carriages up and down. These have essentially the same function for the Z carriages as the belts have for the X and Y carriage. They are threaded rods though because more weight is placed on these parts, and less frequent moving is required out of the Z direction. In general, the thicker these leadscrews are, the better. Thin 5mm threaded rods can become bent and do not last long on 3D printers.