Edit 2/4/19: I have changed, printed, and tested this mount. It works to my intent, and does not collide with any other hardware.
Edit 2/21/19: Per request, I have uploaded a version of this breakout that should not rub the belt, it is the Clearance (CL) version. Let me know if this offset needs to be increased.
Edit 4/5/19: Upon request, I have uploaded a third version of the standoff labeled "TALL" to add another 3mm offset from the gantry plate than the clearance version, for a total of 12mm. I have now uploaded Fusion and .STEP files for both the Clearance standoff (CL) and Tall standoff (TALL). -As the Clearance version has shown success, I will no longer be supporting the original version of this design, now designated "slim." It still works, and I have been using it for months, but the newer designs are improved and the original Fusion archive was lost. -It has come to my attention that the older versions of the 713 Maker parts do not have accessory mounting holes. If you wish to drill your own, the dimensions are uploaded in the comments courtesy of user bwaslo. If you don't wish to drill your parts, I will be attempting a clamp on version of the mount in the near future.
This is a simple mount I designed for a Dual RJ45 breakout boards, intended to mount to the back of a 713Maker Ultralight FT5 carriage. The screw holes for the aluminum plate were designed using the supplied drawings, so they are accurate. The mount fits over the drive belt and does not cause binding or excess friction.
Supports are not necessary. Print as oriented, with the chamfers facing down.
Screw the printed breakout standoff to the carriage plate using 2 M3x12 screws using the supplied hardware threads.
Then mount the breakout board to the standoff using 4 M3x8 screws. These were designed to be a tight fit, the screws will thread into the plastic with enough force.
I am glad to say that this design is getting quite a bit of success, I'm glad you're all enjoying it. If you haven't, if there are improvements I should make, or if your specific use case needs something this design doesn't currently satisfy, let me know! I can't always guarantee a speedy response or upload, but I will do my best.