In Part II I got the charging handle rails in place, mounted back to back on the aluminum mounting posts I'd "milled"... and by milled, I mean attacked with a Dremel, Dewalt hand drill, and a variety of sandpapers until they were useful.
Below you can see the basic setup between the buttons and the TLR.... It's about as simple as it gets: 2x momentary switches wired to the spliced TLR pressure switch cable. This wiring enables either on/off switch to turn on the light.
I added some 24 gauge wire to extend the length from the light to the buttons and wrapped it all in heat shrink tubing to keep the connections safe from the elements. I then used a small pipe bender to bend some 3/16" brass tubing that will guide the cable from TLR to inside the Superlite chassis' handguard and onto the on/off buttons. The next few pictures show the setup.
The brass tubing is held in place along the Volquartsen's rail via a Surefire Micro Scout Light mount. I had one left over from my Space Force 6 build and it was the perfect size to hold the back end of this tube snuggly in place.
The wiring setup was pretty well complete, so I then turned my attention back to the charging handles themselves.
The image below shows just how tight things were getting inside the La Chassis foregrip. I needed to find a way to connect these charging handles to the Superlite's charging handle in a way that: 1. allowed the right and left handles to move independently, 2. we're non-reciprocating, and 3. fit in the tiny space available.
My initial plan was to use ball bearings inside curved copper lines to transfer the motion from the charging handles back to the receiver. After a few days of experimenting, bending copper, and trying to figure out various mounting options, I gave up on this plan.
kimengbk, you were right.
The bearings moved just fine in the curved tube, but there were too many other issues to solve and I was particularly worried that I couldn't mount the various components needed to get the left-side charging handle to work consistently. I had no doubt I could make it work OK in my garage, but there were so many potential points of failure that I didn't trust it working over the long term.
It was time for a new plan. I sacrificed the idea of the right and left side handles moving independently from each other and began working to connect them to a straight rod that would connect to the gun's bolt along the right side.
I cut some 1/16" steel to be the main verticals for the charging handles and then shaped a piece of acetal to brace them to each other. This bracing provided much needed stability for both sides.
I used increasingly large Forstner bits and then sandpaper to cut a half-circle in the acetal so that it doesn't touch the barrel.
The video below shows the whole setup in action. I was very pleased with how easily the parts slide.
And then I realized I was doing it all wrong..... I felt like I'd given up too quickly on a design where the right and left side move independently and I didn't like how little space there was to make truly solid charging handles. This design was probably going to work OK, but I wasn't going to be proud of it.
It was time to rethink the whole mechanism up front.