[unofficial] LowRider v4 DIY CNC, gantry back covers, hinged for opening, and can pop out and back in, plus "tie downs" for them, and an in-gantry Jackpot mount

This is unofficial, not needed for a functional LowRider 4, and offers primarily cosmetic (aesthetic) benefit (for the most part; the “tie downs” do have some zip tie slots that could be used to help with wrangling wires, and the back covers would also keep dust off your wiring etc, while providing a surface that is easy to blow saw dust off of it).

Below are some photos showing my beta test machine with the covers (which went on to be release candidate machine), and using a Jackpot in-beam mount similar to what's provided here. See notes on that below. Back then, I started off with a fan mounted in the cover, but as soon as I needed to lift the cover, the fan and the wires were kind of in the way. The photos are before moving the fan. Now the board mount has a fan mount on it for a 40mm x 40mm x 10-20mm fan, which draws air from the center of the beam and blows it over the drivers, out toward the end of the beam. At least that's how mine is. 

IMPORTANT NOTE: 

First, please print only the hinge nubs and check their fit. See video below. If they don't seat all the way into their spot, then the scale calculation for your print of the back covers will have to be way different. For nubs that don't fit, to scale and reprint until they do it fit, is easy, fast, and cheap. If instead you are “playing around” with scale factors on the main back cover, that's a long print and getting the fit wrong would eat up time and resources. A well-seated hinge nub should stick out by about 0.5 mm from the brace, so 0.5mm x 2 (for both sides) is about 1.0mm of reduction of the opening between the braces, and that is the width you should target for the back cover, by setting that as the Z height for your print of the back cover (they print turned sideways, aka standing up). Please watch this short video to see how the hinge nub should fit:

Now back to your regularly scheduled broadcast:

First up we have the back cover itself, a part labelled as…

• “LR4_Back_Cover_Section” — and since I have not had a chance to design these in a parametric fashion, these will need their Z height adjusted in your slicer. (Since they print standing up, adjusting print height is setting the cover's actual width.) The formula is: 
  • actual distance between your braces - (minus) 1mm = z height for your print
  • example: For my RC3 (release candidate 3) build, my braces had 157 mm of space between them, so I printed these at 156 mm wide, and since they print vertically, that means 156 mm tall (Z height).
  • These have built-in break-away support fins. I included one file without the support fins, merely for in case someone needs it for some reason.
• While making my RC3 (release candidate 3) build, I also ran the wires from the side assemblies into the edge between the back cover and the lower strut plate, which is not necessary. I had the wires in 10mm diameter wire loom hose. Thus there are “MAX” and “MIN” versions of the back covers included. If your wires are going into the holes in the sides of your braces, then ignore these two parts. If you do print these parts, they will need tree supports on at least the overhang where the notch is for the wire loom hose.

Screen shot of back covers:

There are a couple of “extras” provided:

• “Tie downs for wires and back covers (with latches).stl” — These are the “tie downs” I mentioned — Print one per opening between braces. In the screen shot below, it's marked in RED. These have an overhang on the outfacing edge at the back, which is meant to grab onto a lip on the hinged back cover, to latch it in place. In case there are wires or whatever pushing up on the back cover, there are also two M3 screw holes in the tie down, and the back covers have matching holes, so you can use M3 screws to make sure the cover stays in place. NOTE: pay attention to the percent of scaling needed on your slicer settings for printing the back covers, and apply the same percent here, applied along its length. The screw holes might get skewed a little, but should be OK.
• “Placement Jig for “Tie Downs with Latch”” — Only one of these needs printed, marked in YELLOW in the screen shot below. This jig provides placement and centering for the “tie downs” which get attached with small screws to your lower strut plate. . NOTE: pay attention to the percent of scaling needed on your slicer settings for printing the back covers, and apply the same percent here, applied along its length. Its final printed length should be 0.5 mm less than the opening between your braces.

Finally we come to the “hinge pins” for the back covers:

• “Hinge Nubs (SET).stl” — The file is a set of 2. Print one per opening between braces. So, if you have 7 braces, print 6 sets. 
  • These little hinge nubs are made to “press fit” into a hole in the stock braces. Then the back covers can be snapped in place. You may need to “flex” the back cover slightly to snap it in. You can then “open” the back cover by pivoting it upward. It can also be snapped out again for access. Screen shots below show the hinge nubs installed.   

Notes re. the Jackpot in-beam holder:

• I still have this mount in my LR4 RC3 from the beta testing phase. That build includes the FluidDial starter kit PCB from Bart Dring. Below are some photos I found from back during the beta testing phase. In a couple of them I highlighted the connector tower of the starter kit. I think that was because I had to remix the board mount to get the board lower to allow for the starter kit.
• As I already mentioned, the board mount has a fan mount on it for a 40mm x 40mm x 10-20mm fan, which draws air from the center of the beam and blows it over the drivers, out toward the end of the beam. At least that's how mine is. I started off with a fan mounted in the cover, but as soon as I needed to lift the cover, the fan and the wires were kind of in the way.
• The rig was really dusty because the dust shoe was not offered by Ryan until late in the process, and I ran quite a few test cuts before having any dust shoe on it.
• I provided a place on the mount for a buck converter in case you want to undervolt some 24v lights, or want to change from 24v power supply to 12v for other LEDs, or want to undervolt a van to make it quieter, or get 12v out of 24v for a fan, etc. If you don't need a buck converter, it won't hurt to have the spot for it.
• The “tie-downs” feature is included in this building so you could use the same placement jig for the positioning of the board mount.
• I'm uploading one in which the fan mount has a grill, and one with no grill.
• If you use this with the gantry back covers, let me know if it goes smoothly or you have issues. 

I'm also showing here, some photos of the underside of my LR4 RC3 rig with the 24v COB (chip on board) LED strip, which has two rows of the lights, in a single strip that doubles back on itself, showing them both before being turned on, and after. They are really bright.