Thursday, May 22, 2014

Scratchbuilding a Warhammer 40,000 Plasma Pistol Prop

I still haven't been able to get it out of my system, so I find myself building more prop replicas from Warhammer 40,000.  While I've made a chainsword and the various versions of boltguns, I wanted something a bit more challenging.  For my next build, I decided to make a plasma pistol.
Plasma Pistol Completed
In the game mythology, plasma pistols fire energy 'bolts' of bright glowing plasma.  Each one is like a miniature little sun launched out of the barrel.  Among the forces of the Imperium, these weapons are highly coveted and usually end up in the hands of very high ranking officers and heroes of the Imperial Guard.

That sounds cool and all, but I was really just excited to make a pistol filled with blinky lights that chase around inside of it when I pull the trigger and say "pew pew pew."

To see how I went about making it, read on...

Back when I made my Imperial Guard costumes, I needed weapons to arm them.  I turned to my good friend Matsuo to get a handful of his absolutely gorgeous lasgun props:
Matsuo Lasguns

I love the aesthetic of the final pieces, so when it came time to make the plasma pistol, I wanted to make sure that it had many of the same design elements.  That way, the finished piece might look like it was made by the same manufacturer.  At the very least, it would look like it was developed by the same engineers.

For the main body, I started with a scrap of tooling foam and basically carved out the rough shape using a hacksaw and the belt sander.  Finer details such as the vents and seams were cut out with a Dremel and a jigsaw blade:
plasma pistol WIP

Since I'm scaling up from a ridiculously small miniature piece, I took a little bit of license with the exact proportions and contours.  I still believe I managed to capture the appropriate bulk and heft of the design:
plasma pistol WIP

Before filling in the seams and sharpening up the edges of the vents, I gave it a quick coat of paint to fill in the porous surface of the foam:
plasma pistol WIP

I made the power cell that fits into the bottom out of a few pieces of PVC pipe:
Power Cell Rough

Rough Parts Test Fit

The details were added bits of scrap and a plastic Warhammer miniature base I had sitting in the shop:
Raw Power Cell Prototype

Here it is with a coat of paint:
Power Cell Glosscoat

After a bit of sanding and repainting, it was time to box it up for molding:
Power Cell Boxed for Molding

The mold was a simple block mold and the part came out nice and clean:
First Power Cell Casting

The muzzle detail was thrown together from a few scraps of foamed PVC sheet, bits of pipe, and another Warhammer miniature base:
Muzzle Test Fit

I made a block mold for it too:
Molds for Muzzle and Placards
Then cast a copy:
Cold Cast Aluminum Muzzle

Here I am test-fitting it against the finalized prototype for the main body:
First Muzzle Casting in Place

The mold for the main body was made in two parts.  First, I built a clay barrier around the bottom where the pistol grip and the power cell would be inserted.  Then I mounted it to a piece of cardboard and built a drip tray around the muzzle end:

Then the whole thing got coated with some slightly thickened silicone:

Once the rubber was built up and cured, I built a fiberglass mothermold:
Clay Wall Removed

Mothermold Part 2 of 3 Done

After a bit of cleanup, the clay plug was removed, a release agent was sprayed in, and I filled the hole with more silicone.  Once it cured, I laid up fiberglass to hold it in place.  When that had set up, I pulled the whole thing apart, removed the prototype, reassembled the mold, and rotocast the first copy:
First Cast Out of the Mold
Not bad.

For the plasma coil on top of the pistol, I started by shaping some blocks of 3/4" MDF on the belt sander:
Rough Shaping Profile

Then routered a radius into three sides of each piece:
Plasma Coil Parts

Then I glued a piece of 1/4" MDF between the pieces and started filling and sanding to smooth them into one part:
Assembled Plasma Coil

Here it is after a few coats of my standard lightish red prototype color:
Cleaned up Plasma Coil

Here's the prototype boxed up for molding:
Plasma Pistol Widgets 03

I cast the parts in clear polyester resin with transparent blue pigment:
First Cast of Plasma Coil

Here's the first casting out of the mold:
First Cast of Plasma Coil Pulled

I decided I needed a few more details to add to the back end, so I took a piece of my (as yet unassembled) Baneblade kit and pressed it into a lump of clay:
Throwaway Mold for Placards

Then I sprayed it with some mold release and poured in some resin:
Quick and Dirty Castings

The result: a decent pair of double-headed eagle placards:
Placard Castings Raw

After a bit of trimming and cleanup, I boxed them up for molding:
Cleaned Up Placards Ready for Final Mold

They're in the little mold on the left:
Molds for Muzzle and Placards

At the rear end of the pistol body, just above the grip, there are a few more details.  The first one looks like a small fuel tank of some sort.  Here's my rendition:
Plasma Pistol Widgets 01

Here it is with the rest of the detail bits for the area:
Plasma Pistol Widgets 02

I made a quick mold box for them as well as a control knob to add to the back of the pistol:
Plasma Pistol Widgets 04

Once I'd cast two sets of those parts, I had all the bits I needed to assemble the complete pistol:
First Full Set of Parts

Here it is after some quick trimming and cleanup:
First Cast Stuck Together

I think it fits:
Dangerous Me with Plasma Pistol
I also think I needed a new dust mask.

Once I'd sanded the shine off of the whole thing, I added a bit of spot putty to some minor flaws:
Plasma Pistol Body Prepped

Then I primed it and coated it with satin aluminum metallic paint:
Plasma Pistol Body Basecoat

Here's everything fitted together:
Plasma Pistol Fit Testing

The muzzle would be added on last to make it easier to install the lights:
Plasma Pistol Assembling

To make the plasma coil blink as if there's bolts of energy moving from one end to the other, I installed a blue LED Sequencer Kit from Nightfire Electronics.  Of course, I had to make a few special modifications:
Soldering Lights for Plasma Pistol

Since there wasn't enough clearance under the coil to fit in the sequencer, I ended up drilling holes into the bottom of the casting to fit the LEDs, then adding long leads so I could attach them to the board separately.  Once it was all soldered together I got this blurry video of the plasma coil in action:

And here's the whole assembly being shoehorned into the pistol:
Plasma Pistol Wiring Complete
After installing some perforated aluminum into the vent details and giving the whole thing a blackwash, it turned out like so:
Showcase Plasma Pistol

Here it is paired with a re-sized chainsword prop:

Pew pew pew:

This particular piece is only one small part of my upcoming female Commissar build:
Rose Test Fitting Commissar Armor

So stay tuned...

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  1. Love the variable speed LEDs....very cool

  2. When will we get to see a motorized chain sword? If Im pure of heart and wish really hard I think it could happen. Super nice plasma pistol!!!!!

  3. Does this Matsuo chap sell those replica lasrifles? Have you a link?