Introduction: GWAR -Oderus Urungus - the Cuttlefish of Cthulhu Rubber Latex

I'm not a pro as you will soon find out, but I am having so much fun making this stuff and I've learned so much, I feel I have to share for both the fun of it and to maybe help somebody else out in their quest to make their own pieces.

So I made this using a 2 piece box mold. In hindsight maybe I should have tried to do maybe two molds because it ended up being very heavy and awkward to work with.

The main ingredients:


Ultracal30 (Plaster)

Oil clay (homemade)

Water clay (Crayola)

Monster Makers RD-40 latex

Monster Makers latex mask paint

Hot Glue

expanding foam insulation (Great Stuff)

Wood for the box (various)

carving tools (cheap set from Harbor freight)

lots of chip brushes (gotta love Harbor Freight!)

Step 1: Step 1. the Sculpture

So I started with the basic shapes. I used a piece of 3 inch PVC pipe and a Styrofoam cone. For the eyes I used 2 lengths of 3/8" air hose. After that it was adding and shaping the clay. I would not consider myself much of an artist, but I did the best I could :)

Step 2: Molding the Eyes (and Wings)

My first ever mold! Since it would be extremely difficult (maybe impossible) to make a mold with the eyes and wings still on the cuttlefish, I made them separate.(I did not take any pics of the wings, but they were made using this process).

Special note on the wings: In order to get the wing membranes thin enough, I couldn't get the clay to work that thinly, so I cut pieces of cardboard from a Coke box and inserted them into the sculpture when I began the molding process. It was kind of a pain to scrape the cardboard out of the mold afterwards, but the final result was good :)

1. I made a brick out of water clay for the oil clay sculpture to sit in (pic2). This acts as a temporary bottom for the plaster mold while the first half is being poured. Note: Oil based clay will not stick to water based clay, making it easy to remove the clay after the first half of the mold is done.

2. Built the box around the mold (pic3 and 4). Some people use clamps to hold the boxes together, I used hot glue and more water clay inside and out to tightly seal all cracks and seams. I sprayed the inside walls, clay and sculpture with PAM cooking spray to help insure the plaster would not stick to anything. Don't forget the registry marks (indents) when the mold is done, this will help it fit back together properly.

Note: I forgot to put clay pry marks in this mold! Luckily I got it to pop using the little open spot in the mold near the bottom of the eye's antenna.

3. I mixed the plaster and poured it into the box. I used Ultracal30 which enabled me to pop the mold within a few hours, though I waited another day or two to make extra sure it fully cured before making the second half.

Note: Ultracal30 is a plaster with a catalyst in it that allows it to kick off and harden very fast. It also makes a very strong, durable mold that can be used several times. Also, to reduce the chance of air pockets in the plaster, tap the sides of the box or pound lightly on your work table (causing a vibration) to help get all the bubbles to rise to the surface. You don't want an air void it your mold....

4. After the plaster cured, I dismantled the box and removed the temporary clay, being carefull not to pull the sculpture out of the plaster (which I accidentally did...). Make sure all of the water clay is carefully cleaned off the first half of the mold before starting on the other half. I let it set overnight for the water clay to dry which made it a bit easier to clean off. Making the second half is exactly the same process as the first except that the registry marks and pry points are already done. Viola! It ain't pretty, but it's done(pics 5-7) :)

5. So they way I applied the latex to this bad boy was: I painted the inside of each half of the mold with latex, let it set for about 30 min. then did one more layer (the monster makers latex is pretty thick). I also painted the outside edges. Yes that causes some extra flashing but it also helps guarantee no splits in the seam!!

After the second brushing of latex had set, I closed the mold tightly using some big rubber bands. I then used one of those syringes used to feed toddlers liquid cold medication to inject the latex in the small hole in the mold I left at the base of the eye antenna. I let that drain back out for about 30 minutes and then repeated the process 3 times and let it cure over night.

Note: Always to remember to powder the inside of the part with baby powder (I used corn starch). Though the latex is cured, it will stick to itself and the powder prevents that

Step 3: The Body

So the body of the cuttlefish was made in just about the same way as the eyes, exept on a much larger scale. I bet this mold weighs at least 50 LBS and I had to secure the mold halves with ratchet straps. Plus I remembered the pry points! LOL Also I left the base open in order to pour in the latex, just like the eye mold


I had a gnarly air pocket right in the Cuttlefish's 'brow' that I filled with oil clay to try and fix. When I pulled the latex part from the mold, the latex was uncured in that spot. I don't know if it was thicker there and I didn't give it enough time to cure, or if the oil clay prevented the porous nature of the mold to draw moisture from the latex which helps in the latex curing process.

I found out that GWAR uses a specific kind of 2 part expanding foam to back fill their props like this one. the process is to put the piece in it's mold, secure it, and pump it full of the expanding foam. Any excess will be pushed out of the hole in back of the mold and can be later cut off. The foam they use was looking too expensive for me so I got a bottle of expanding insulation foam from the hardware store. Followed GWAR's procedure while mounting the wood support shaft in the foam while spraying it. I had to brace the wood support rod so the foam wouldn't push it out while expanding and curing. I waited 24 hours and popped it. It turned out great! (See pic8). But! A few days later it started to warp and sort of implode. It didn't wreck the piece but twisted it a bit. IDK if it didn't cure properly inside and began to collapse? The foam sticks to the inner walls of the latex so it sucked the latex down with it and caused some funky warping. You will see in the next step the warping which very noticeably tweaked the eyes out a bit

Note: Always to remember to powder the inside of the part with baby powder (I used corn starch). Though the latex is cured, it will stick to itself and the powder prevents that

Step 4: Attaching the Eyes, Wings, Painting and the Belt

1.Attaching the eyes: I ran wooden skewers down through the latex and foam and mounted the eyes over the skewers I then super-glued the eyes on at the base and coated with latex.

2.The wings: Basically the same thing. I trimmed down the spikey protrusions on the body and used a thick guitar string because the skewers were too fat for the wings. Super glue and latex. I also trimmed the wings down to look more gnarly like Oderus'

3. I brush painted this. Wish I would have waited to get my airbrush set up going. Doesn't look bad, but airbrushing would have been better. I used Monster Makers latex mask paint. It was formulated to use with their RD-40 latex and comes ready to spray through a airbrush. You need to use latex paint so it can flex with the part. If you don't the paint will crack and look crummy

4. I have no pictures of the belt but: I bought a cheap leather belt. I made a base out of 7/16" OSB with 2 bolts running through it. A top bolt that mounts through the belt, and a bottom bolt that mounts to the cuttlefish and brings it closer to crotch height. A couple large washers for support behind the bolts. I also used a thick piece of leather on the back to protect my skin from the wood and metal and to add a little more stability.

5. I bought a dread-lock wig that I cut a piece off of and cemented to the base for pubes with Barge (glue).

6. I made a 12" strip of spikes out of oil clay and did a small 1 piece box mold. When done, I airbrushed them black, then added some white over the black spikes to give it more of a metal look. I glued these strips to the belt using more barge brand cement.


Oderus77 made it! (author)2017-04-04

Please i know the width was 3" how about length. I really need to know

slave524 made it! (author)slave5242017-04-08


It was about 12".

Oderus77 made it! (author)2017-04-04

How long was the piece of pvc used to make the cuttlefish?

jimmy.thomas.5095110 made it! (author)2015-04-22

thanks for posting this i been trying to find this info for a bit im gonna wake me one to gt with my mask

seamster made it! (author)2014-09-30

Nice techniques!

slave524 made it! (author)slave5242014-10-13