Have you noticed that your 3D printer prints slowly with less quality with a TPU filament? We bet that your printer uses a Bowden drive extruder instead of the direct drive if you have one. Although the Bowden drive is no less an extruder than the direct drive, something about it makes it perform poorly with exotic filaments.

So, if your extruder comes with a Bowden drive, you may have to convert it to a direct drive extruder to maintain your print quality across all filaments. So, what qualities make one extruder drive perform better than another? How different are their results? This article will answer these and several other pertinent questions that cross the mind of 3D printer operators who use the Bowden drive.

And if you are wondering what to do to modify your 3D printer, thats the primary purpose of this article -- to show you how to convert to a direct drive in detail.

What Is a Direct Drive 3D Printer?

A direct drive printer is a printer design that has the extruder sitting on top of the printhead. This orientation allows the extruder to feed the hot end with the filament directly. As a result, your extruder has better control of your filament. The direct drive printer is versatile and ensures that you maintain the same print quality across a wide range of filaments.

What Is a Bowden 3D Printer?

The Bowden drive printer is a printer design that mounts the extruder on the frame of the printer. The extruder pushes the filament through a longer PTFE tube and into the hot end in the Bowden printing design.

If your printer uses the FDM technique, if you aren’t printing with a direct drive, your printer is a Bowden drive printer.

How to Convert to Direct Drive

Many printers, especially the Creality printers, do not have a direct drive extruder. So, to get the best experience across filaments, converting to direct drive becomes necessary. Converting your printer to a direct drive requires nothing more than a change of extruder orientation. That is, you will only need to get a direct drive extruder and replace the Bowden drive extruder with it. While this may sound straightforward, an incorrect conversion can cause more problems for you and your printer. Therefore, you must get it right, and getting your conversion to a 3D printer done right begins with following the right procedure.

To carry out this conversion, you will need a wrench, a set of Allen keys, extension cables for your stepper motor, and a support bracket. Most, if not all, of these tools, will come with your direct drive extruder kit. Once these tools are available and you turn your printer power off, we are ready to begin.

Here are the steps for converting your Bowden extruder to a direct drive.

1. Detach the extruder wire but not from the mainboard.
2. Disconnect the PTFE tube and the PTFE couplers from the hot end and the feeder end.
3. Use the Allen key to unfasten the screw that holds the extruder feeder to the motor and bracket. Don’t forget to steady or keep the extruder to prevent it from falling off while you unfasten the last screw.
4. Again, using your Allen key, loosen the screw of your fan shroud.
5. With the large-size Allen key and your wrench, loosen the screws of the nuts that maintain the X-axis carriage on the extrusion. The nuts, spacers, and bearings should come off.
6. Next, attach the bracket to the X-axis carriage with your hands.
7. Replace the screws and nuts on the X-axis carriage. Don’t bother about the spacers. Ensure that your eccentric nuts are not too loose or too tight. A nut that is screwed in too tightly will impede the movement of the roller bearings of the X-axis carriage. On the other hand, when your screws and nuts are too loose, it can reduce the quality of prints.
8. Separate the carriage from the hot end by loosening the two screws that bind them together. Afterward, screw the PTFE coupler without the hot limitation.
9. Attach the motor and screw the feeder system to the bracket with four screws.
10. Attach and fasten the screw of the PTFE to the feeder.
11. Introduce your new stock extruder wire to replace the older one, which remains connected to the mainboard. Attach your new wire to the extruder.
12. Your hot end needs a PTFE tube to come in. Cut a suitable length of the PTFE tube (begin with a 10cm length) and push it into the hot end. You can check if the PTFE tube has the appropriate length by placing the hot end beside the screw holes. Reduce the size of the PTFE tube if you discover that it is too long until you achieve the right length.
13. Fix the hot end to the X-axis carriage while the PTFE tube is in place and connect it to the feeder.
14. Put the fan shroud back in place and if available, place the BLTouch sensor and bed-leveling sensor on top of it.
15. Set your retraction and speed to a suitable level. Your retraction shouldn’t be too high or too low. Too low retraction will lead to filament oozing and, consequently, a stringy print. On the other hand, too high retraction can cause the hot end nozzle to jam. There is usually a conflict between speed and quality of print. While we don’t want to spend forever on a print, it’s not a bad idea to sacrifice print speed for quality prints is not a bad idea. You will derive your greatest satisfaction from a quality print than how quick it was to round off the printing process. It is perfectly fine to lower your printing speed till your printer achieves quality print.

Advantages of Direct Drive Printers Over Bowden Printers

As we have earlier seen, the Bowden printers deliver the same result as the direct drive printers except in certain conditions. So here are the advantages of the natural drive printers over the Bowden printers.

1. Easy Retraction

Retraction is the ability of the printer to suspend the flow of filament while moving the nozzle to a new print position. Retraction is one of the strengths of the direct drive printer. Unfortunately, the Bowden drive’s retraction in individual filaments leaves much desired and is responsible for filament oozing. When oozing occurs during printing, the final result comes out poorly, with trails of tiny strings appearing all around the print.

2. Easy extrusion

Extrusion has to be smooth to guarantee high print quality. The ease of extrusion gives the direct drive printer an edge over the Bowden printer because it can more effectively supply the hot end with filament when required.

3. Filament versatility

The direct drive printer doesn't face any additional challenges with filament material. It maintains its quality. Bowden printers are prone to several malfunctions with certain types of filament in terms of print quality.

4. Lower power consumption

The printer uses power in pushing filament through the extruder drive gear and out of the nozzle. The longer the distance between the extruder drive gear and the nozzle, the higher the power needed to supply filament. The extruder drive gear and nozzle of a direct drive printer are close together and require less power to push the filament.

How to Get A Direct Drive Extruder

You can order a direct drive extruder online from amazon or similar ecommerce platforms for as low as $35. Finding the direct drive extruder that matches your printer shouldn’t be on your list of worries as there is no want of variety in the market. There are direct-drive extruders for all brands of printers from the Creality to the Micro Swiss direct drive. The fantastic thing is your extruder kit can come with the complete conversion package. Apart from the plugin wires, screws, springs, and bolts, your kit will contain many printer spare parts like an extra hot end, fans, fan brackets, and stepper motor. So now you can convert your printer and have different parts for keep.

Conclusion

There are several reasons why you may or may not see the need to convert your 3D printer from a Bowden printer to a direct drive printer. Your choice will largely depend on your scope of operation and reasons for 3D printing. The direct drive printer can maintain quality of various filaments.

With a more straightforward retraction system, you can rest assured that the days of losing valuable time and getting a print that is marred with strings are behind you. Apart from the freedom to print with different filaments and still retain quality prints, getting a direct drive printer doesn’t cost much. And there’s more.

You get the complete conversion kit and an exciting collection of extra spare parts that you can keep for the rainy day. In addition, the conversion process is relatively easy, but only if you thoroughly follow the proper steps. In no time you should get your direct drive printer up and running and enjoy the freedom to use any filament of your choice.