With the growing popularity in urethane rubber armor and props (including the new pauldrons and shoulder straps in our own shop), we figured it would be a good time to share some of our favorite techniques for getting paint to stick to flexible rubber pieces as well as how to attach them to your costume. We also use these same exact techniques on a lot of our semi-rigid pieces as well since they also have some flex to them. Please keep in mind that these tips are for urethane rubber armor and props, not silicone.
Surface Prep
The absolute most critical part to painting rubber pieces is, unsurprisingly, the most important part to painting anything – surface prep!
Your number one enemy to getting paint to stick to your parts (rubber or otherwise) are the oils on your skin, followed closely by chemical residue from the mold the parts came from. You will want to ensure you are wearing gloves (we prefer nitrile) anytime you handle your parts. Once the gloves are on, the first step we take on any part is to wash it with warm soap and water. We prefer Dawn since its gets everything off anything.
While it isn’t necessarily a requirement for everything, we like to ensure all oils and contaminants are gone before trying to paint urethane and after the initial washing, once the part is dry, we use Duplicolor Prep-Spray to do a final cleaning. Prep-Spray is sprayed on in a wet coat, then wiped off with a clean, dry cloth.
Painting
Imperiflex & Alumaluster
We’re going to start with the cream of the crop, which also, unfortunately is the most expensive option, but it is the way most film productions paint rubber armor, ESPECIALLY if you are looking for a high-gloss metallic finish like on our Jane Foster Mighty Thor costume.
Our process for high gloss chrome on urethane rubber parts consists of using Imperiflex and Alumaluster from Imperial Surface. The smallest unit of each of those will set you back about $500. It definitely isn’t priced for the average hobbyist, and as much as we love it, we can only use it on projects where the customer is willing to pay for it. That being said, it is the top tier and you definitely get what you pay for. A little also goes a long way. With just those starter kits we painted to complete Jane Foster suits and helmets along with a dozen other armor and helmet pieces.
The other caveat when using professional grade paints like this is that, you absolutely must use proper ventilation and personal protection – a respirator for organic vapors, gloves, and goggles should be your bare minimum, and they require a higher level of spray equipment – an HVLP gun versus an airbrush. We use this kit, though just like with airbrushes, there are a wide-range of options.
Our process for applying these materials is fairly straightforward, though takes time and patience, once we’ve done the surface prep already mentioned.
- Spray a light coat of Imperiflex.
- Wait 10 minutes. (may vary depending on temperature and humidity).
- Spray a second medium coat of Imperiflex.
- Wait 12-24 hours.
- Spray a light coat of Alumaluster.
- Wait 10 minutes.
- Spray a second medium coat of Alumaluster.
- Wait 24 hours
- Spray a light coat of Imperiflex.
- Wait 10 minutes. (may vary depending on temperature and humidity).
- Spray a second medium coat of Imperiflex.
- Wait 12-24 hours.
- Spray a light coat of Alumaluster.
Wow, that’s a lot of coats! Yes, but there is a good reason we do it this way. Any clear coat, even Imperiflex, WILL slightly dull a chrome finish though Imperiflex does so less than anything else we’ve experimented with. So if you want the chromiest chrome finish, you need your top coat to be your chrome paint hence the final coat of Alumaluster. Yes, this does mean your final coat of chrome paint is unprotected, but first off, its chemically bonded pretty well with the Imperiflex and is almost impervious. However, nothing is impenetrable, and if any of your chrome does get worn or scratched off, a very slightly duller version will show through and be almost visually imperceptible and may even look like regular wear and enhance the look of your part.
Duralumen and Spazstix
If you want a high-gloss chrome finish but need to save yourself some money, we have two other paints we can recommend in place of Alumaluster.
Duralumen from Digital Armory is very similar to Alumaluster and we’ve used it with Imperiflex with great success. In our opinion it is a darker chrome finish than Alumaluster, but depending on your desired look that isn’t necessarily a negative. While it can be sprayed via airbrush, we’ve found it looks much better when we shoot it through our HVLP gun.
The cheapest option we’ve used for a chrome paint is Spaz Stix Mirror Chrome. Spaz Stix can be found in both small rattle cans as well as airbrush ready bottles. Spaz Stix is a much brighter finish than both Alumaluster and Duralumen which makes it a little less realistic looking as a chrome, but it is still a great option especially if you’re on a budget and it does indeed also play well with Imperiflex.
Other Paints
To go along with this guide, we decided to do a test on a a couple of our rubber shoulder straps of several different base layer and paint combinations. On one strap we did four different combinations of base layer and paints. On the second strap, we did a more chrome finish. The video and test results are near the end of this post!
For purposes of our tests we used 3 different bases along with 3 different paints. Please keep in mind that there are endless variations of primers and paints that could also have great results, but these are our most commonly used ones.
Bases
For our 5 tests, we used Duplicolor Plastic Adhesion Promoter (PAP) in combination with Montana Gold Spray Paint, PlaidFX Primer with PlaidFX Flexible Paints, and Pure Acetone with Montana Gold Spray Paint, PlaidFX Flexible Paints, and Duralumen Chrome Paint.
For the PAP test, we did a light coat of PAP, waited 5 minutes, did a second coat, then waited 10 minutes before spraying the Montana Gold over the PAP. You do not want to wait too long between your final coat of PAP and your paint as the goal is to bond them together.
For the PlaidFX primer test, we brushed on a wet coat of primer, waited about 10 minutes, then did another coat of primer. Since we were brushing it on, we like to do the two coats in alternating directions (horizontal strokes on the first coat, then vertical on the second) to ensure complete coverage and to help smooth it out. Once the second coat had dried for about 10 minutes, we did the first coat of the PlaidFX flexible paint, waited about 10 minutes, then did a second coat. We alternate directions on the paint as well.
For all three tests using Pure Acetone, a shop towel is dosed with Acetone and the part wiped down then paint is applied immediately after the acetone has dried/evaporated (needless to say proper ventilation and protection should be used with this method). This one is potentially the trickiest because if you rub the acetone too much, you can actually damage the urethane rubber, but that’s also why this method is our preferred. The acetone “opens the pores” on the rubber allowing your paint to chemically bond with it. We wet our towel and do one pass across the part in a single direction and then let it dry before applying paint. That’s all you need! The PlaidFX paint was done in two coats over the acetone while the Montana Gold and Duralumen were both applied in a single coat.
If you’re interested in more info on how we use PlaidFX paints on our builds, this video we made goes into depth on how we use PlaidFX on rubber and even semi-rigid parts specifically to get a Clone Wars animated-style look.
Durability Testing
So how did it all work out? We made a quick video to show how these methods stacked up against seven durability tests. The final results are below, but please watch the video to see the tests in action!
- Soft Bend Test – Do the paints crack or chip off with a soft bend?
- Tape Pull Test – Using the crappiest masking tape we have, does the paint pull off?
- Sharp Bend Test – Do the paints crack or chip with a very sharp bend?
- Nail Scratch Test – Can the paint be scratched off with a finger nail?
- Blade Scratch Test – How easy is it to scratch the paint with a blade?
- Sanding Test – How easy is it to remove the paint with sand paper?
- Pick Test – Can the damaged paint be easily picked and peeled off?
We were actually quite pleasantly surprised at how well ALL of our test variations held up! They all easily withstood the easier tests and showed no signs of wear or cracking on the bend or tape tests, and only showed minimal surface marring under nail scratch tests. As expected, the thinner the paints, the better it held up to the blade scratch and picking tests with the thin coat of Duralumen doing the best and the thick PlaidFX doing the least well, but still holding tight and resisting our best efforts to pick the paint off.
Alternative Paints
While we haven’t tested these ourselves on urethane rubber parts, we have heard from several folks that these also work well on rubber armor and props. We have used them on EVA foam armor and props which need to hold up to even more bending, flexing, and crushing than urethane rubber and have had excellent results though so feel pretty comfortable recommending them as an alternative.
Attachment
One of the great things about using urethane rubber for armor is that it takes CA glue (super glue) REALLY well! Like most folks, we use hook and loop for attaching most of our armor and urethane rubber is a great candidate for gluing hook and loop right to it. Our favorite glues for this are Bob Smith CA Glue – Extra Thick Maxi-Cure and Loctite Gel Control Super Glue. Honestly, these two are our go to glues for almost everything we do!
The process for gluing urethane rubber to itself or to something else is pretty straightforward.
- Mark off where you will be attaching hook and loop
- Lightly scuff the area with sand paper, scuff pad, or steel wool
- Apply a thin coat of CA glue
- Stick on your hook and loop – if the piece allows for it, put a weight down on top of it while it cures, otherwise just hold it in place.
That’s it! Now your rubber armor is ready to wear! We hope this helps you with your own rubber armor painting and attaching. Happy costuming!
If you’re interested in our rubber pauldrons or shoulder straps, check them out in our shop. We are looking to make other rubber armor pieces in the near future, so feel free to leave a suggestion in the comments below or via our contact form. And if you’re interested in commissioned rubber armor (or anything for that matter), check out our commission request form.
