3D printers are all about extruding filament through a hot end and laying it down on the print bed to create a model. Not all extruders are the same, though. The two most common types of extruders in FDM 3D printers are Bowden and direct drive extruders.
So what’s the difference between Bowden Vs direct drive extruders, and what are the advantages and disadvantages of both? The key difference is where the extruder is mounted. Let’s dive in.
What’s a Bowden configuration?
If your 3D printer has a Bowden configuration, it means the extruder stepper motor is mounted on the frame of the 3D printer rather than on the hot end itself. The extruder pushes filament through a PTFE tube into the hot end. This makes the hot end lighter, allowing for faster print speeds.
Bowden extruders have their pros and cons, which we’ll see below:
What are the pros of a Bowden extruder?
The main advantage of the Bowden extruder is the reduced weight on the print head. Stepper motors are rather heavy, so by moving the stepper motor off of the hot end and mounting it onto the frame, the hot end has much less inertia as it moves. This means your 3D printer can handle faster print speeds without any added vibrations.
The Bowden setup can also let the hot end travel much further, which is why you’ll see printers with larger volumes have Bowden setups rather than direct drive setups.
If you’re looking for a dual-extruder setup, the only way to go is with a Bowden setup, neaceb
What are the cons of a Bowden extruder?
Because the stepper motor of a Bowden extruder is so far from the hot end, you need a powerful motor to push the filament. It also means you need faster retraction speeds and greater retraction distances to avoid stringing. In older printers, Bowden extruders did not do so well with flexible filaments, either.
The stronger motor may not seem like that much of a disadvantage, but the retraction issue is a big one. You may find that Bowden printers struggle with printing very fine details that require lots of constant retraction.
Also, it takes quite a lot of tweaking to get Bowden extruders to work well with flexible filaments. Because there’s so much room between the extruder and the hot end, flexible filaments sometimes snake out of their path and end up getting jammed.
Finally, the PTFE tube can be damaged by abrasive filaments like wood fill and metal fill. You will need to replace the tube ever now and then to get the same print quality.
Which 3D printers have Bowden extruders?
Common 3D printers that use a Bowden setup include the Creality Ender 3, the Creality Ender 5, CR-10, and Tevo Tarantula.
Direct Drive Extruders
What’s a direct drive configuration?
In a direct drive extruder setup, the stepper motor is mounted on the hot end itself. The extruder motor pushes the filament directly into the hot end. There is very little room between the extruder and the hot end.
What are the pros of a direct drive configuration?
Since the direct drive extruder feeds the filament directly into the 3D printer hot end, there is very little room for things to go wrong in the extrusion process. As a result, there is less possibility for extrusion-related issues, and the filament can be expected to reliably feed into the hot end.
As an added extrusion-related benefit, the reduced distance between the stepper motor and the hot end means retraction will also be more reliable. You’ll be able to get away with lower retraction speeds and retraction distances, too.
Also, due to the reduced distance, the stepper motor does not need to be as powerful. In fact, there are special “pancake” stepper motors that you can use for direct drive extruders that are both lighter and have less torque.
Finally, thanks to the absence of a PTFE tube, you can use more exotic and abrasive filaments without any issues. In the earlier days of 3D printers, Bowden extruders were notoriously bad at handling flexible filaments.
The only you could print flexible filaments back then was if you had a direct drive extruder.
What are the cons of a direct drive extruder
The added weight from a direct drive extruder may cause some unwanted vibrations in your prints. To remove this ghosting, you would have to print at slower speeds.
Also, the direct drive extruder position makes it harder to reach the hot end and nozzle in case you need to do any maintenance or fixes.
Which 3D printers have direct drive extruders?
The Wanhao Duplicator, Monoprice Maker Select, and Prusa MKIII are all examples of printers that have direct drive extruders.
Conclusion: Is a direct drive extruder worth it?
A direct drive extruder is worth it if you’re going to print lots of highly detailed prints that require accurate retraction settings. You’ll also do good to stick with a direct drive extruder if you print with lots of abrasive filaments.
Direct drive extruders happen to be more expensive, though, so if you want to save some money, stick with a budget printer that has a Bowden extruder. You’ll get nearly similar performance.