Hardware Projects

Powering Hot Toys 1/6 Scale Figures with DIY Battery Replacements

I wanted to to light up some 1/6 scale figures easily without having to flip switches or replace dead batteries.

The Soap Reactor is the go-to solution for this but it’s expensive and hard to buy so I decided to go the DIY route with a little help from a Facebook post, some coworkers, and friends.

Pros and Cons

Before we get started, let’s look at the tradeoffs for each of our power supply options.

Proswireless, easy setup, included out of the box
Constedious to turn on/off, risky to leave in (corrosion), need to be replaced eventually
Soap Reactor
Proseasy to turn on/off, nice looking battery cells, easy setup, no battery replacement required
Conswires, hard to buy in US (I honestly couldn’t figure out how to buy), expensive base unit, requires purchase of additional battery
cell replacements, limited number of terminals so additional base unit required to power more cells
DIY power supply
Pros easy to turn on/off, no battery replacement required, materials available online, cheaper than soap reactor, essentially unlimited cells, more flexibility with cable management, fun project (if you’re in to that kind of thing)
Conswires, More difficult to set up, more expensive than batteries

What You’ll Need

Terminal strip, JST connectors, Wire stripper, JST crimp tool


  • JST connectors
  • JST crimp tool
  • electrical wire
  • wrapping wire
  • terminal blocks / terminal strip
  • conductive tape
  • plugs
  • adapter with led barrel connector
  • super glue


  • tweezers – useful for setting JST connectors and installing battery cells
  • multi-meter
  • project box
  • Phillips head screw driver
  • wire stripper
  • power drill
  • 1/8 cable sleeve

Building Your Own Power Source

Here’s What I’ll be Powering:

FigureBattery Count Description
War Machine4 x 3 x 1.5v Head, Hands x 2, Chest
Iron Man Mark344 x 3 x 1.5vHead, Hands x 2, Chest
Hulkbuster + Jackhammer Arm8 x 3 x 1.5vHead, Arm, Jack Hammer Arm x 2 Chest, Legs x 2
Other stuff in the future??????

I needed to power 16 cells (or 48 batteries total). Each terminal holds 3 x 1.5v batteries (for a total of 4.5v). They vary in size of batteries but I don’t really care about that because they’re all the same voltage and I’m making my own replacements that I can cut to size.

The Power Supply

Adjustable adapter to barrel connector to electrical cable to JST connector

I’ll start with an adjustable adapter set to 3v (this one came with a led barrel connector) – It probably wouldn’t hurt to set it at 4.5v but I’m staying slightly under powered just to stay under the full rating. Batteries aren’t going to output a full 4.5v either. Ideally I’d set it at 4v but that’s not an option on this adapter and I didn’t have much luck finding a 4v adapter.
I ended up purchasing a 3.3v adapter and a separate led barrel connector so I’ll have 2 in case I want to take any of the figures out of the display and power them separately; this has been really useful for reposing and maintenance.

From the barrel connector, I run electrical wire to a JST connector. I put JST connectors at every link so I can plug/unplug different parts quickly and easily and I don’t have to twist wires or solder anything.
JST connectors require a special crimp tool that cost me $30 so if you opt out of the connectors and the tool for another connection method, you can save around $40

Splitting Connections

I used terminal blocks when I need to split one wire out to 3 or 4 – with the exception of the Hulk-Buster where I needed 8; this would get ugly with a terminal block so I got a strip instead.
I ended up using a terminal block for each of the suits (with 4 connections) and one in the display cases to split the wire coming in between the middle and top shelf. From the terminal blocks/strip I connected a short length of electrical wire with a JST connector that will connect to the “last mile”

for the connections between the terminal blocks/strip and the battery replacements, I twisted blue and black wrapping wire using a power drill.
Just connect one end to a doorknob and the other to a drill and pull the trigger. I cut the twisted wire in to strips long enough to allow for cable management. You’ll want to hide your wires and tuck them in where you can so it’s not a straight line to from the battery to the terminal.

For the battery packs, strip the end of the wrapping wire and cut off a thin strip of the conductive tape for positive and negative. Wrap the conductive tape around the wire in to flat squares, then superglue them to a plug (or whatever you use) that you’ve cut to fit in the socket. I always glued positive (blue) to the bigger end for consistency. You’ll want a JST connector on one end for connecting to the terminal and a battery pack on the other.

Cable Management

For the Figure

I took advantage of any opening I could find to weave the wires through the figure so they were well hidden. Then I used scraps of the black wrapping wire to twist around groups of wires to keep them neat before wrapping them in a 1/8 inch sleeve.

Don’t worry about the screw on battery covers; most of them won’t accommodate the wire sticking out and they’re hidden by outer panels. I ended up with a bunch in plastic baggies when I was finished

Display Cable Management

To hide the terminal blocks, I used a couple of black plastic project boxes. I drilled a hole in both ends for the wires and used some rubber rings to make them look clean. Then I carefully crammed everything in and closed them up.

Turning it all on

What fun is a single power supply if you can’t turn it on with the click of a button? The last step was plugging the power supply in to this wireless remote control outlet.