Cinema Drillpack Project
This project was born out of the blatantly obvious overlap of high current portable power tools and the high current requirements of cinema cameras. I have had the wonderful experience of repairing and operating blockbuster cinema cameras, and one of the major hurdles of operation is maintaining clean power output under high load.
Two competing standards came about for the cinema industry, largely stemming from broadcast TV. Back in the late 80s to early 90s, it was not uncommon for camera grips and DOPs to wear battery belts. Yes, a belt of NiCad battery cells. Today, you would not be found dead wearing one of those. Gold mount and V-mount batteries are by and large the two current day standards used throughout the cinema industry. One can argue that Sony's NP-F and Canon's BP battery are also competitors but let's save that for later.
When Dewalt released the Flexvolt battery in 2016, I immediately noticed the benefit of having a switched voltage high current pack, especially one that uses the new 21700 format cells. The true Achilles heel of cinema batteries is the obscure nature of the standard. Nothing else utilizes gold mount or V-mount - just cinema cameras and relevant accessories. This is the polar opposite business model that consumer power tool companies sought after. Why limit a battery to just one task? Why not take over the world? That's exactly what the tool companies did. You can now buy a Makita battery powered coffee maker. A Dewalt 20v radio. A Ryobi 18v hot glue gun. A Milwakee red max heat gun. a Hitachi/ Metabo battery shop fan. There are battery lawnmowers now.
With the doom and gloom of cinema mounts inevitable, I began my tireless searches for genuine Dewalt 20v connectors. I scraped the Stanley service net and eventually found the suitable 20v connector, but not the entirely populated connector that would allow me to be able to talk to the battery and read cell voltages and potentially balance externally.
Like any good project, it starts off with taking something that already exists and modifying it for another application. In this case, Wooden camera made a RED DSMCII camera power adapter that was very basic. It featured a single sided PCB that took power input from a gold mount plate, and transferred cell information and whatever proprietary handshakes required to talk with the camera across the DSMCII port. The Wooden camera adapter featured a very straight forward construction, which served as a good starting point to what a cinema camera adapter based on a drill battery would look like.
I ended up CADing a similar custom mount out of aluminum with additional mount points to enable some future ideas I had in mind for the battery adapter.
Want more? Here's a behind the scenes look at my workspace and some of the images that did not make the cut to be included in the write-up: