Ender 3 & CR10 part cooling duct base: CR/BL Touch and Spider Hotend

Originally I didn't like that I would need to find/buy screws and nuts for mounting everything and was just planning on making smaller holes, then I realized that the mounting bracket design was too thick for use with the 4mm screws I had, there was no way to mount a CR Touch bracket, the cross bars in the fan opening made a lot of noise with the fan and a lot more support was needed when printing than I felt it should need.

I've designed it to be printed upside-down, set your support threshold to 15-18 deg and use a single layer 4-6mm wide brim. When its done you can start the screws for the CR/BL Touch supported by the supports before removing them. There seems to be some deviation between E-Plates so you may want to save some of the brim to use as shims when mounting the CR/BL Touch. In my case the Ender 3 needed shimming because it wants to go deeper than the nozzle, but the CR10 doesn't. There is also a miniscule amount of play in the mounting holes so it can be adjusted up and down by about 0.3mm.

100% compatible with the 4010 ducts created by BikeTiger.

Widened lower opening to allow it slide on past hotend mounting screws.

Thinner back plate to allow mounting with stock screws.

Narrower and hexagonal fan and touch sensor screw holes to allow mounting with stock screws without nuts.

Removed cross braces in main fan opening.

Modified internal geometry for better printing.

Made a deeper version for use with larger hotends.