Multicolor Filament (5 color) Extruder Feed Block for Bowden Hotend

thingiverse

This is a versatile 5-filament feed block manifold, designed to accommodate multiple filament feeds from 1-5 extruders using Teflon feed tubes. A convenient clamping system is integrated into the design, which secures the Teflon feed tubes at the inlet ports, eliminating the need for commonly used 4mm pneumatic fittings. All components are produced in a single print and are not subjected to heat, as it mounts prior to the Bowden infeed tube. The outfeed port is threaded with a 1/8 NPT thread, which fits standard Bowden threads using an 1/8 NPT joining nipple. Alternatively, a 4mm pneumatic fitting can be used on the out-feed and connected to a Teflon joining tube. This device is ideal for loading up to five filaments at once, as extruders are relatively inexpensive on gearbest. Simply switch the extruder plug prior to printing to select the desired filament. If you have a 3-color feeder system, you can retract the filament approximately 120mm until it withdraws behind the manifold combining funnel and then feed the next color filament into the hotend. The manifold block contains small, precise filament tubes, requiring accurate printer calibration for optimal results. Avoid using supports as they cannot be cleaned from internal filament guide tubes. Also, refrain from using stringy filaments like PETG, as strings may need to be removed. You will need M3 x 30mm nuts and screws (x4) and a 1/8 NPT joining nipple (available at hardware and plumbing suppliers), along with Teflon feed tubes. Due to the tapered nature of NPT threads, they tend to split and crack laminate lines in the print, so a split line is printed into the design, secured by M3 screws. All clamping components are marked with a dot for alignment during assembly. The feed blocks used on our machines are mounted directly to a bowden head and function well. They were designed specifically for ABS Plus with shrinkage rates factored in; if you use other materials, minor scaling adjustments may be necessary. I have also created mounting brackets for a diamond head, available at Thingiverse (https://www.thingiverse.com/thing:2333015). However, after using it for several weeks, I encountered issues with filament back-feeding tubes not in use and reverted to the single Bowden head. This manifold system has proven more effective for my needs. If you find this useful, please share photos and hit the like button. Additionally, a YouTube demonstration video is available (https://www.youtube.com/watch?v=YuY5K-6wZcI), showcasing the 5-color extruder feed manifold in action. The script-written video demonstrates the feed system by extruding 50mm of filament, retracting 130mm to clear the conversion funnel, and pausing for 10 seconds before feeding the next color. You can program this system for 3 colors using a 3-color motherboard or use it manually with the standard Anet motherboard as demonstrated. Update: I have added extra files, separated clamps for printing separately, opened filament holes in the manifold block from 2mm to 2.6mm, and ensured proper internal chamfers on short Teflon feed tubes. This updated version has proven more effective.