In part two of this cosplay tutorial, I will be going over how to apply bondo over your prepared surface. In the last article, our prepared surface was fiberglass. Fiberglass adds a hard, shell-like base to your armor, but bondo will give you that perfect, flawless finish. Bondo is a two part putty that is spread on your prepared surface like thick peanut butter then dries to a rock-hard, sandable shell, which will give your a perfect smooth, unmarred surface that has incredible durability. Bondo, like fiberglass resin, is made of polyester resin and is not safe for indoor use. Remember to have your respirator and other protective equipment on hand, and work in a well ventilated area. Also like fiberglass resin, bondo cannot be directly applied to foam surfaces. Foam projects can still be used in your projects with bondo, but the foam surface must be protected from direct contact with bondo. Bondo can be purchased at most home improvement stores as well as auto repair stores.

Bondo: Difficulty – Advanced (hazardous, requires special equipment)
Supplies Needed: Organic vapor respirator, coveralls, disposable gloves, bondo applicators, disposable cups, plastic spoons, bondo, bondo hardener (generally included in bondo purchase), safety glasses, primer, sandpaper in grits from 80-400. Suggested: Dremel tool, mouse sander.
Pros: Extremely durable, can be sanded to a perfectly smooth surface, waterproof.
Cons: Heavy, requires special tools to use, not safe for indoor use, messy, produces lots of sanding dust.
Time: Prep – 1 – 2 minutes. Work time – 5 minutes.

Once your have your protective equipment on and your fiberglassed armor ready, you are almost ready to apply your bondo. Your can of bondo will come with a tube of red hardener. Do not let bondo or the hardener come in direct contact with your skin. With the hardener still capped and closed, carefully squeeze the hardener tube to make sure the contents are mixed thoroughly. Opening the bondo, you will see it is a thick, grey goo. Once mixed with the hardener, bondo has a very short working time. You never want to mix too much bondo, or else it will just go to waste once it starts to harden. Read the directions carefully on the bondo can to find out how much hardener you will need per how much bondo you are using. Once you are ready, mix the hardener and the bondo until it is a uniform color with no streaks of red or grey remaining. Take your bondo spreader (or putty knife) and spread the mixture over your project like you are making some sort of deadly peanut butter sandwich. You will have irregularities, so don’t worry. Bondo is sandable and is a multi-part process. Depending on how perfect you want your final surface to be, you will be doing multiple applications of bondo.

Once your bondo loses that peanut butter consistency and starts to get crumbly, stop! Toss out your partially cured bondo and mix up a fresh batch if needed. Thankfully, bondo has a fast cure time, so hang tight. Continue spreading your bondo over your surface until you have everything you want covered, covered. Prepare to sand sand sand! Using a rough grit of sandpaper, you will want to grind down those high peaks or lumps, then move to finer grits once your surface is more even. Bondo dust is going to get everywhere, so be aware. Once your bondo surface has been sanded somewhat smooth to the naked eye, take your primer and give the entire sanded surface a healthy, even spray. Primer will allow you to see the dips, pits and irregularities in your bondo surface that you may have missed before. It is helpful to mark these pits with a marker for quick reference later.

Mix up some more bondo and patch up your irregularities. You will have to repeat the process multiple times to get your surface perfectly flawless. Bondo, sand, primer, sand, repeat. Congratulations! These are the basics of bondo.

 (picture is bondo’d shoulder after primer)

Christina Sims is an amateur cosplayer and costume creator from Colorado. She currently works with Apotheosis Agency staffing gaming tradeshows. She has been a costume contest finalist at Blizzcon in 2008 and 2009 and took first place in 2010 for her depiction of the female monk from Diablo 3, as well as been the US face for Alexstrasza the Life-Binder for Cryptozoic Entertainment. For more information on Christina and her costumes, please visit Zerina Cosplay at facebook.com/zerinacosplay.

Discuss this article in our forums!

Share/Bookmark