Hypercube Hotend Mount for Chimera and BLTouch

The Chimera mounts I found for the hypercube were all bad matches for my bed position and some were straight-up broken meshes, plus I needed to edit them to clear the bolts holding the HC x-carriage to the bushes. I also had a devil of a job trying to get bushes to slide smoothly on my CF tubes - crosslaid are much stronger than pultruded, and vibrate less, but the outer diameter is very variable and even hours of careful sanding with 200-grit wet cloth wasn't able to get it totally even.

So I had 3 goals:

1. Create a hot-end mount for the chimera clone that fitted neatly without needing loads of cut-outs, that could take a 40mm part-cooling fan.

2. Design bushes that would run smoothly over slightly lumpy CF tubes without introducing more wobble than already there.

3. Mount the sensor somewhere that wouldn't add limits to X or Y travel.

The first bit was pretty easy - E3D make the tech drawing available and I borrowed the part-cooling fan duct from https://www.thingiverse.com/thing:2305218 so placing the screw holes etc was done with that in mind.

The second item was achieved by making the PTFE-lined bushes (https://www.thingiverse.com/thing:1739340) a little bit bigger diameter than I had before so they were a touch loose, then extending them to 80mm. This allows them to slide easily, creates no additional wobble as the length constrains angular movement, and also gave me enough room to add a dovetail mount, which was important for point 3.

The third requirement is met with a little sliding bracket. The dovetail is not super-tight so setting the perfect sensor height is a doddle, but is contrained enough to not move when the lock-screw is put in. Using a dovetailed bracket also means making a mount for other accessories and sensors is easy.

I will be adding simple mounts for 8mm and 12mm proximity sensors when I get a few minutes, but the dovetail design means almost anything light that touches the bed gently could be mounted, like e.g. a pen, without disturbing the hotend. Some day I might try designing a multi-colour ink-spray to dye nylon prints on-the-fly...

EDIT: Added a little widget to separate the bowden tubes so they don't cross over each other and brush the fan (noisy!). They are sized for 1.75mm capricorn tube but with a 4.2mm ID they should be fine with most similar tubing. I've clipped the tubes about 4cm above the top of the hotend clamp and that seems to do the trick nicely.