Rondo!

OK, today we take the next step in creating the Space Marine™Mark VII helmet - Rondo!

I have to admit, when I read that term the first time I was a bit confused. I wondered why you'd pour this

Rondo - Slam it Down!

into a helmet and expect anything good to happen. This unfortunately dates me as a child of the 60s & 70s. Rondo for our purposes today is a combination of fiberglass RESIN and BONDO body putty. The resulting mixture pours easily, but sticks to what it touches, cures relatively rapidly, and forms a nice hard shell.

Here's all my material gathered together and ready to mix:

Presentation is everything

We need:

• The art object in question
• A mixing board - I found some cheap poly boards at a local grocery store (6 for $4!)
• A selection of bondo putty applicators
• A putty knife for scooping out bondo from the can
• A mixing cup
• Bondo repair putty and hardener
• Fiberglass resin and hardener

Mixing up Rondo is a bit of black magic, as everyone has their own recipe. For this project I mixed:

•  A baseball size lump of Bondo
•  3/4 of the Bondo hardener that the instructions call for
•  3 oz of fiberglass resin
•  22 drops of resin hardener ( the instructions call for 30 drops - 10 drops per ounce).

The altered hardener ratio is to slow down the catalysis that hardens the bondo and resin, giving me some extra time to coat the inside of the helmet.

 

I mixed the Bondo and hardener, and the mixed the resin and hardener. Finally, I mixed the two together to form the Rondo. The resulting consistency is the thickness of pancake batter. 

 

The Rondo gets poured into the inside of the helmet, and then spread with a rotomolding sort of motion (that means rotating the helmet while tilting it to cover the desired surface).  It took two rounds of Rondo to completely coat the inside of the helmet:

 

 

First coat completed

Second coat completed

Between the first and second coats, I plugged up the eye holes and breathing hose holes to minimize any drippy mess like so:

See no Rondo, Hear no Rondo, Spew no Rondo

This stuff cures exothermically, meaning the damn thing gets HOT! It's hard to do, but if you're stubborn or insensitive to painful stimulus, you could burn yourself, so use a little caution when handling the helmet as it's curing. I had about 10 minutes of working time with the mixture listed above, which is just about perfect for this kind of job.

If you're familiar with Shawn Thorrson's blog, you probably know that he likes to be able to do step aerobics on his helmets. While cool and photogenic, it's not something I'm into. One complete coat of Rondo seems to be plenty for this build. So, once this is completely cured and cooled, I'll move onto smoothing the exterior and prepping for the final finish. I'm still dithering about whether to make this a one off, or make a mold helmet and produce clones... Oh well, I'll burn that bridge when I get to it.