My Lightplacer build of January 2021
Build notes in no particular order:
The cable, 24 AWG shielded was selected for its size and flexibility. They use about 1/4 the capacity of the cable chain, and are easy to work with. The X and Y limit switches use one cable each, saving 2 cables in the chain. The cable easily handles the current draw from the motors without getting warm.
The TinyG enclosure was found on a 3D print website and mounts easily to the frame of the Lightplacer. This keeps the cables short and manageable. https://www.thingiverse.com/thing:745369
I fabricated a pc board to hold 2 mosfets and 2 diodes for driving the vacuum and solenoid valve. The mosfets I used were massively overspeced but I use them in other products and had them is stock. There are many others in an SO8 package that would work fine. This board is shared on OshPark. https://oshpark.com/shared_projects/BAFElEDY
A second board was fabricated to add a switch for the Z limit switches to reverse them when switching between Liteplacer and OpenPNP. Also shared on OshPark. https://oshpark.com/shared_projects/8oBLMgzI
A 3rd board makes a clean interface in the TinyG controller for the led power leads. Also shared on OshPark. https://oshpark.com/shared_projects/RTm1xfcH
The table was selected based on another builders choice that looked like it would work well. It turned out to be a good choice, being very rigid but light-weight, and definitely low-priced. Care must be taken to not over-tighten the wood screws that hold down the LP frame. The 4 corners where the legs attach are reinforced internally with solid wood, but the rest of the table is just cardboard inside. I have included 2 photos of the hole removed by a hole saw to provide for the up-camera view.