RingConn Gen 2 Size 9 Protector (Print-in-Place)

Having looked for a protector for a RingConn Gen 2, I found all the options to be flawed for one or more of the following reasons:

• Made of silicone, so drags on clothing and surfaces, which is uncomfortable and sometimes causes the ring to twist into the incorrect orientation on the finger.
• Poor choice of colours (transparent looks very cheap).
• Oversized as they're designed to fit all smart rings on the market.
• No locator marking to provide tactile feedback to indicate whether the ring has rotated or not.

I decided to make my own that's about as small as possible with a 0.4mm nozzle. This way, I can pick whatever material and colour I prefer. There's a small locator bump which you can identify with your thumb (assuming you wear this on an index finger) to let you know that your ring hasn't rotated into an incorrect orientation without needing to remove the ring.

This model is designed to fit a RingConn Gen 2 Size 9. 

WARNING: Printing this could ruin your RingConn if you don't know what you're doing. Read these instructions carefully. A slow printer with a hot print bed could cause a fire. You assume all risk in deciding to proceed.

Print Settings

Nozzle size: 0.4mm
Layer Height: 0.1mm for ALL layers. You might be able to use a different layer height and adjust the instructions below with respect to layer counts, but I've not attempted this. Proceed at your own risk.
Material: Only tested with Prusament PCCF
Orientation: Lay flat so that the hole is perpendicular to the print bed
Skirt: 10 perimeters - make sure your initial Z offset is perfect. You don't want sharp, bulging edges, nor do you want poor adhesion and the thing separating from the bed during the final stages. If your print does separate from the bed, you could end up ruining your ring.

Printing

You'll want to run two trial runs to ensure things go smoothly for the final print.

Trial 1: Ring sizing

You should test that your printer is accurate enough to print the case for the size of the ring.

• Print up to and including layer 76
• Abort the print
• Insert the ring with either the left of right side adjacent to the locator marking (note that the top of the ring is slightly concave while the bottom is convex, so ensure the top and bottom are properly oriented)

Layer 76 at 0.1mm layer heights is where the print starts to envelop the top edge ring when laid within the model. If you're able to place the ring within the aborted print and it does not protrude whatsoever beyond the height of the print, you should be good to go ahead with the actual print.

Trial 2: Print interruption

You should test that you're able to properly resume from a paused print:

• Pause at layer 76.
• Move the toolhead out of the way by a known Y offset.
• Wait 30 seconds (or however long you think you'll take to insert the ring).
• Move the toolhead back into position by reversing the Y offset above.
• Resume printing.
• Ensure the final few layers take no more than a minute or two to avoid prolonged heat exposure to the ring.
• Ensure the model prints correctly - if you have any layer shifts or separation from the print bed, you'll need to work on your technique or better tune your printer.

You'll likely have some roughness on the top few layers due to overhangs, this is normal and may end up slightly better on the final print due to the ring acting as a support.

Production Run

• Pause at layer 76.
• Move the toolhead out of the way by a known Y offset.
• Insert the ring and ensure it is flat and flush with the bottom of the printed model. It must not protrude beyond the height of layer 76 whatsoever. You must do this as quickly as possible as the heat from the print bed will be soaking into the ring. Prolonged exposure to heat could damage the battery, or worse, cause a fire.
• Move the toolhead back into position by reversing the Y offset above.
• Resume printing.

Removal

You’ll have to carefully pull the layers apart to get the ring out. Since the protector uses a tight friction fit, it can be difficult to extract the ring even once you’ve broken an end open.

Resizing

You can probably fairly easily resize this model to fit other rings by applying a scaling factor, but I can't provide any assistance here.