Linear Rail Z Axis Bracket Adapter

I was working on adding linear rails to my Ender 3, however with the [Z axis linear rail setup](https://www.thingiverse.com/make:899298) I'm using, it originally requires to buy new screws for the Z axis, and at the time I was building it I didn't have any extra screws lying around. So I went and used the organic design of the dual Z axis adapter from Proper printing and basically built it up from scratch (as the model was an STL and it was really hard to modify).

The type of linear rails I used are the MGN12H rails; I have only tested this on an Ender 3 since that's the only printer I have.

I recommend printing the part out orientated with supports like in the last picture


--Update 3/16/2021--

Added V3 version and right side for dual Z (which is V3), these use POM nuts instead of brass nuts, and they do not use brass inserts. For the right side, you must use M5x40mm length bolts, the stock ones will not fit. When I installed the right side, I had to use spacers under the