Gunaseelan Murugesan
The two most popular types of feeding systems for FDM 3D printers are Bowden and direct extrusion. Both systems work by gripping onto a plastic filament with a stepper motor and feeding it to a hot end, which melts down the plastic onto the print bed. Although each type of feeding system has its pros and cons, both provide an effective means for delivering filament to create high-quality 3D prints.
Bowden systems have revolutionized 3D printing with their increased reliability and ease of use. By positioning the stepper motor on the frame and using a tube to connect the filament spool and hot end, makers are not only ensured that their filaments will feed in evenly but also that they won’t snap or stretch from constant movement.
On the other hand, In Direct extrusion systems, the stepper motor that regulates the filament is mounted directly onto the hot end of the printer, making loading and unloading filament easier than ever. This system does not require as much tubing as traditional systems; despite this though, it still uses a small amount of tubing that is kept in place at all times above the hot end, allowing for smooth and glitch-free operation.
Bowden tubes naturally differ from direct extrusion systems in terms of benefits and drawbacks. Learn more by reading on!
Pros of the Bowden Tube
The lighter printhead offers notable advantages in terms of acceleration, jerk, and speed for CoreXY printers. Moreover, the motors will be under less strain due to reduced torque requirements for the same speeds. Hence, it’s also possible to enjoy more accurate prints with minimal ringing effects on the parts. In other words, you can benefit from faster printing times combined with an improved level of accuracy.
Also, Working on the extruder should be much easier when using a Bowden setup, since the motor won’t have to be detached and such tasks are harder to complete. Having less stringing and oozing with PLA might also attribute to this configuration due to the extended retraction distances and slower speeds that are able to withdraw filament more regularly from the nozzle.
While there are definitely some advantages, one should still be conscious of any drawbacks that may come with this technology.
Cons of the Bowden Tube
When deciding if a Bowden extrusion setup is right for your 3D printing needs, it is important to consider both the advantages and disadvantages of the method.
First, it eliminates excess weight from the printer head and can provide relatively high travel speeds with low torque requirements on the print head. However, due to its design, a greater retraction distance will be needed in order to prevent stringing and blabbing.
Additionally, a more powerful stepper motor as well as an increased force will be required in order to force the filament around the bend of the tube.
Even with a powerful feeding stepper motor, your maximum flow rate may potentially be reduced due to the accumulative friction of the filament moving along the tube. Flexible filaments such as TPU are a great solution for specialized applications, however, these types of materials may not be suitable for certain tasks. This is because these flexible filaments can compress and expand inside the tube with retractions, creating possible challenges in tuning in settings appropriately.
Various Options Available
If you’re looking to upgrade your 3D printing experience, investing in a better type of tubing may be the answer. There are many different varieties of tubes available which all offer their own advantages; some are designed to reduce the risk of kinks forming in the tubing while others come with interfaces specifically designed for 3D printers.
Capricorn tubing is becoming increasingly popular, especially for those using longer Bowden tubing runs and flexible filaments. Not only does it have a smaller inner diameter to help with retraction issues, but it also has patented additives that raise the temperature resistance of standard PTFE tubing, allowing users to explore higher-temperature technical materials without having to upgrade to an all-metal hot end. Users of this special type of tubing attest to experiencing dramatically less filament wear since their nozzles and other components are protected from higher temperatures
Solving a common issue of clogging due to charred Bowden tubes near the nozzle has never been easier with today’s 3D printer technology, particularly if you upgrade to Capricorn or TH3D. Both brands are gaining a reputation for their reliable performance and high-quality products, especially when it comes to filament extrusion for 3D printing.
The installation process is quick and straightforward–it only requires disconnecting the two tubing clamps from the original tubing and replacing them with a new one designed specifically for that model of printer. Be sure to securely attach it down close to the nozzle, otherwise, an air gap can form which can have negative effects such as clogging and excess stringing on prints.
Final Thoughts
When it comes to choosing between a Bowden extrusion setup and a direct one for 3D printing, there’s no definitive answer for everyone.
Factors such as the materials being used and the desired speed and precision must be taken into account before making a decision. For instance, if you are looking to produce models quickly and accurately then a Bowden setup might be the better option, but when using filaments with higher flow rates or materials that require more flexibility to print well then a direct extrusion setup might be best.
One additional factor is whether or not you already own a printer with an extruder set-up – this eliminates part of the decision-making process but can also give you the opportunity to switch your current setup if you wish.
Gunaseelan Murugesan
Experienced Project Engineer with a demonstrated history of working in the field of Product Design & Development industry in Mechanical Engineering. Skilled in 3D Printing and Re engineering Technologies with CATIA V5 , Materials Science, Finite Element Analysis (FEA), Mimics, ANSYS Workbench and Casting Simulation software. Strong engineering professional with a Master’s Degree focused in Industrial Metallurgy from PSG College of Technology, Coimbatore.
