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.

At long last, RESIN!

So-

Way back in December I started messing around with Pepakura, specifically helmets from Games Workshop's Space Marine™ universe. After hacking together a Mark III and a Terminator helmet, I finally did it right with the Mark VII:

The other two are perched on my computer room window sill as a testament to my rather pedantic manual dexterity skills.

Finally today, only 6 months later, I finally got around to taking the next step, applying fiberglass resin!

 Mk VII and equipment in ready mode

As I said when I blogged about this the first time, I got sucked into this after stumbling across Shawn Thorsson's blog When My Brain Leaks, the Drops Drip Here. Shawn has a wonderful step by step walkthrough of this process here. I'm going to give you the Reader's Digest version...

In the picture above, you'll see everything you need:

• Pepakura model, in this case the Mark VII helmet
• Fiberglass resin with hardener (which is hiding under the white cap)
• Graduated mixing cup
• Chip brush. Pro tip - buy the cheap ones, because the resin is really hard on brushes
• Gloves - you don't want this stuff on your hands. Nitrile gloves are cheap, impervious and  and grippy
• Wax paper coating the work surface. The resin sticks to everything, and once hard doesn't like to let go. The wax paper will keep you from wrecking your model when you try to pry it off the table.

You'll want to perform this job outside, or in a really well ventilated space. Huffing resin fumes is a great way of killing brain cells.

The process is pretty straightforward. Measure out the amount of resin you'll need. In this case I ended up using about 6 ounces to coat the whole helmet inside and out. Then add the hardener. #M resin asks for 10 drops of hardener to one ounce of resin. Be sure to read the instructions and use the right amount for your resin brand. Too little and it'll never harden right. Too much and you'll have a mixing cup resin popsicle. Mix the resin and the hardener thoroughly, and then brush onto the model.

Some folks do just the inside, some just out. I did both sides because I had enough, and I really wanted to make sure the paper was impregnated. The point of this step is to make the model stiff enough to take the Rondo mixture that comes next without deforming.

The result should look something like this:

See, I told you the hardener was hiding in the cap...

Note the mottled appearance. That's good, as it means the resin is soaking into the paper.

Now it hardens, and puts the lotion on its skin, or it gets the... oops! Wrong blog.

Once it's hardened completely, the next step is to coat the innards with Rondo, a mix of resin and Bondo body putty. So stay tuned for more mess!