Building a Replica of the M55 Tactical Nuke Launcher from Starship Troopers

 A while back, some friends and I put together a squad of Mobile Infantry costumes based on the science fiction classic "Starship Troopers" so we could strut around at WonderCon in Anaheim.  We had a pretty good time:

The aftermath made for a fun pile of stuff in the hotel room:


Now if you've been following my blog for any length of time, you'll recognize a whole lot of things that have all come out of my shop.  In earlier articles, you can read about the making of the Morita Assault Rifles (LINK), Morita Carbines (LINK), and the armor (LINK and LINK) but now it's time to see how we maked the M-55 Tactical Nuke Launcher.

Read on...

The first challenge in replicating this particular piece of kit was finding decent reference images.  Aside from a few screen captures from its brief appearance in the film, the best pictures I could find were from auction listings:

Still, these were few and far between.  Luckily, I was able to get a hold of Ethan Johns, owner of the screen-used original:

He sent me tons of detailed photos with measurements:

You can see them all in this album: LINK.

So, armed with all of these detailed photos, I put my guy Jeff Santos to work on a digital model of the launcher.  In pretty short order, he'd come up with most of it:

I was confident the size was right, but still surprised by how small the actual thing was in this digital test-fit with a 3D scan of me:


Over the next few days, we printed out the parts.  I don't find that process particularly interesting to watch, so I didn't take any photos.  But once we'd glued the body together, sanded down the print lines, and given it a couple coats of primer, it looked like so:


Of course, I have this odd compulsion that makes it nearly impossible for me to make just one of anything.  So I needed at least two of these.

Printing and prepping another copy of the whole body would take more time and effort that I really wanted to spend, so I opted to make a mold of that part.  After a few more rounds of sanding and filling, the main body was given my customary coat of gloss light red:


Once that was dry, the whole thing was mounted up for molding.  This was a task for Andrew the Intern:


Once again, we'd be making a matrix mold, so step one was to cover the prototype with a sheet of plastic, then build up a clay matrix with keying strips and pour spouts built in:

This was then covered in fiberglass:


Then the whole thing was flipped over and the process was repeated on the other side:


When the fiberglass mothermold had cured, it was pried off of the part and the clay was removed:


With the clay cleaned out, the mold was bolted back together, the edges were taped to prevent any possible leakage, and the void where the clay used to be was filled with silicone rubber:


Once that cured, we flipped it over again and removed the clay from the other side:


Then a generous layer of mold release was applied before bolting the mold back together and filling the second side with silicone.

When that cured, the mold was opened up, the master was removed, and the mold was prepped for casting:




For the barrel, I used a length of aluminum tubing which would be captured and held straight by the mothermold:


The plan was to rotocast the main body.  I refuse to own a rotocasting machine because I prefer the controllable results that can be achieved by rotating the molds by hand.  But since the mold would have to be kept in pretty constant motion for ten to twenty minutes at a time and this mold contained enough gravity to give me a serious case of the I-don't-wanna, I was going to have to scheme.  

With the tube in place, the mold was bolted shut and plywood wheels were added on each end:


Then I poured in a batch of urethane resin just big enough to build a thick coat over the inside of the mold and started rolling it around.  To the right:


Then the left


Then the right:


Then the left:


Then the right:


Then the left:


Then the right:


Then the left:


Once the layer in the mold had cured, this process was repeated three more times to build a thicker, stronger shell.  Then the mold was opened up to reveal the first casting:


Gorgeous.

Meanwhile, Andrew was hard at work setting up the two-part mold for the lower rail.  I wasn't paying attention to what he was doing, so this is him pouring silicone while I hoped he did a good job of building a watertight parting wall around the part:


Nothing leaked out of the mold box at least, so that was good:


The next day I snuck into the shop on the weekend and flipped the mold over and removed the clay wall to find out that that kid had done good.  There were plenty of registration keys and no silicone leaking through to the other side.  So I cleaned off any residual clay and sprayed on a release agent:


Then poured the second side:


On Monday I pulled the first cast out of that mold:


In no time at all, we assembled the first copy of the nuke launcher:


Here's Rachel trying it on:


Since I was suddenly in a rush to get ready for WonderCon, I finished this assembly with a 3D printed butt pad and sight housing before giving the whole thing an olive drab paintjob to match the rest of the arsenal:


Then we installed sling mounts:


Finally, Rachel did the blackwash to weather the whole thing:

It came out pretty great:


Here it is in the hotel room before we started outfitting the rest of the squad:


Once we all mustered up, it was time to get into armor and head down to the convention floor:


Here we are, loading into the dropship, AKA "elevator:"


There was no shortage of shenanigans once we were out in public:


At some point, we handed the nuke launcher to General Rico for inspection:


Then it was time for drinks:


So that wraps another fun cosplay adventure:


Stay tuned for more...