These are 3D-printable mounts for the Beeline Moto navigation device suitable for the Royal Enfield 650 Twins (Interceptor 650 and Continental GT 650). They require the use of the original insert from a Beeline mount.
There are two versions: one with a hole for installing an M3 heat-set insert and one "tapped" to take the screw directly.
A heat-set insert is a threaded metal insert that can securely accept a screw or bolt. These are typically installed using a soldering iron. This is the best practice for using screws with plastic prints, and it is what I would recommend for the Beeline mount.
In the US, heat-set inserts can be readily obtained from McMaster-Carr, Amazon, and other vendors. A specialized soldering iron tip makes installation easier, but is not really necessary.
Some people told me they wanted to get one of these printed, but the heat-set inserts intimidated them. I have therefore provided a version with a "tapped" hole that can theoretically be screwed into directly. I use "'tapped'" and "theoretically" because while the threads in the hole are modeled, your results may vary considerably depending on your printer and material. You might want to run a regular tap into the hole.
I am not a mechanical engineer, but my guess is that if this connection were to fail, it would be while attaching and detaching the unit into the insert, rather than when you're riding down the road. The Beeline is light and the connection is not subjected to that much stress, so I would think you could get away with screwing the insert straight into the print. But there's no question a heat-set insert is going to be more secure.
I make no warranty for the safety of your motorcycle or navigation unit, and cannot be held responsible for any issues that arise from your use or implementation of either design.
Install the OEM insert in the print's seat using your chosen screw method. The seat is keyed so the correct orientation should be obvious.
The mount attaches between the gauge cluster and cluster bracket: remove the 10mm acorn nuts and washers, lift up the gauge cluster, position the print so that the provided holes are lined up outside the rubber washers on the cluster bracket.
Re-attach the cluster to the cluster bracket, making sure th print remains correctly aligned. Replace the washers and acorn nuts.
My initial intention had been to design the whole assembly into the print, but as I started looking at it, it became apparent how much engineering had gone into that little insert. The inner assembly is suspended over a small gap, with a certain amount of "springyness" that didn't happen by accident. Similarly with the two small tabs that rise above that inner assembly to click it in place. It must have cost Beeline some money to manufacture it this way; if they could readily mold it in one piece they would have done so. Getting these parts to be "springy" like that while also being robust on a 3D printed part would be quite difficult. That's why I elected instead to use the OEM insert.
I'm very pleased that you're interested in the design, but I am not interested in taking on the task of printing and shipping these. If you do not have access to a printer (and in North America and Europe, check around -- you'd be surprised at what your local library, makerspace, or Fab Lab may have available), services like Shapeways will print files on demand for a reasonable price. PCBWay recently started offering 3D printing and I have heard some good things; the price they quoted me for this print was almost shockingly cheap.
I'm interested to hear your feedback on how this can be better, and if you have a suggestion I find interesting I will consider making additional changes, but I am not really in the design-for-hire business. If you're really keen, you could try hiring someone on Fiverr, but you'll need to be able to spec out exactly what you want.
How much you need to worry about this is going to depend on the material you print it from and where you store your motorcycle, but there's no reason you can't apply a weatherproof coat of spray paint or something similar.