Yet another cooling assembly for Ender 3. It probably also works for CR-10 and other Creality printers with the standard hotend. The part cooling "fang" uses superelliptic cross-sections, partly for airflow efficiency but not the least for mathematical beauty.

The modular design is inspired by the original design by ozfunghi with most screw locations, etc. in the exact same places, to make it possible to combine with modules from other remixes.

The hotend can be cooled with various 40x40 mm fans, including the super-quiet Noctua 40x40x20. To force as much air as possible to passthrough the hotend cooler, the duct is tight on the fan side of the cooler but open on the back and to the sides.

The part cooling fang is smooth to allow for the air to flow with minimal resistance. The fang exists in four versions; one for the original 40x40x10 radial blower, two for the 5015 radial blower, and one for an axial 40x40 fan. If using a 5015 blower, the new reversed version is recommended.

How I Designed This

All parts are designed in OpenSCAD in the form of manually written source code. The smooth fangs are the result of 3D-spline curves, calculated using the scad-utils library for splines. Around these spline curves, superellipses are generated in order to build the inner and outer meshes.

The eccentricity of the superellipses varies with the height, but the exponent is constant at 2.5, except at the very top, where it goes towards 2 for the circular fan but to infinity for the rectangular one. Incidentally, the value 2.5 is used in some famous superelliptic artwork, such as the big fountain at Sergels Torg in Stockholm, and also the superellipse-shaped tables by Bruno Mathsson and Piet Heins.

Updates

2020-09-04

Added an experimental version of the back plate with an arm to hold a BLTouch to the left of the fang.

2020-06-20

Added a version of the duct to mount a BLTouch sensorinside the duct. This placement makes it possible to come close to the nozzle with the probe, and it does not seem to interfere too much with the airflow.

2020-06-08

Added a reversed variant for the 5015 blower. This does not interfere with the bowden tube during printing because the fan itself is extending forwards.

2020-05-20

Added a version of the fang for the 5015 radial blower.

Files

*superfang-plate.stl - Backplate to attach everything to the printer *superfang-plate-bl.stl - Backplate with BLTouch mount (untested!) *superfang-clip.stl - Small clip to fasten the backplate on the right hand side *superfang-duct.stl - Hotend cooler duct *superfang-duct-bl.stl - Hotend cooler duct with internal BLTouch mount plate *superfang-fang-4040.stl - Part cooling duct adapted for 40x40 axial fans *superfang-fang-4010.stl - Part cooling duct adapted for the original 40x10 radial fan *superfang-fang-5015.stl - Part cooling duct adapted for the 5015 radial fan *superfang-fang-5015r.stl - Part cooling duct adapted for the 5015 radial fan, reversed

Only one of the fang-files is needed, depending on your part cooling fan.

Only one of the duct-files is needed, depending on if you want to mount a BLTouch probe inside the duct or not.

Printing

Most parts can be printed without support, except for the small clip which needs support for the nut space. The fang versions for the radial blowers (40x10 and 5015) have a very small contact area with the build plate; it may be good to print them with a brim to assure that they stay firmly on the build plate.

I printed this in PLA with a 0.4 mm nozzle and 0.2 mm layer height. It is probably wise to use a more heat resistant material if you often print at high temperatures.

Assembly

To assemble, you also need three M3x10 screws, one M3x16 screw, and four M3 nuts. The nuts in the mounting plate can easily fall out when you push the corresponding screws in; use a drop of glue to make them stay in place while assembling.

BLTouch

There are two different ways of mounting the BLTouch sensor. The first is the somewhat unconventional center mounting inside the cooling duct. This puts the sensor close to the nozzle, making it possible to probe a larger part of the build surface. The second is the more conventional mounting on an arm extending to the left of the cooling assembly.

To mount a BLTouch inside the duct, use the superfang-duct-bl.stl file for the duct. You can use two M3x6 screws with nuts. It can be a little hard to get these screws into place, since you can't reach them with a screwdriver. There are slots in the duct to allow for the wires from the BLTouch to come out at the top. The offsets from the nozzle is zero in the X-direction and -24 mm in the Y-direction.

To mount the BLTouch on the left side, use the superfang-plate-bl.stl file for the backplate. In this case, the offsets are -43 mm in the X-direction and -15 mm in the Y-direction.

Category: 3D Printer Parts