Tools on Tuesday: Hot Knife

About a year ago I became interested in working with EVA (Ethylene Vinyl Acetate) foam, a dense and somewhat rubbery material commonly found in craft stores (often in the form of model kits for kids). I was looking for a way to make colorful, lightweight yet durable sculptural shapes that didn't involve painting. I found myself a great tutorial about working with EVA foam and got myself the recommended tools and a few 1 mm sheets to play around with. As the tutorial had warned, I found the foam extremely hard to cut well. You need to use as few strokes of the cutting blade as possible, or else you'll get raggedy, uneven and/or choppy-looking edges. And you CANNOT trim, shape, or otherwise fix said edges after the fact. It just makes a mess---both of the cut piece and your work area!

What a mess!

And I thought that if I really want to make nice-looking things with EVA foam I should use a heavier grade of foam, which would be even harder to cut well. More research led me to the tool I needed: a hot knife. Then life intervened and I had to put my exploration of EVA foam on hold. Then, this past Friday I found out that I didn't get in to the renowned Renegade Craft Fair in June. Wah. So on Saturday I took myself to Michaels for a consolation prize. I still had three packs of 3 mm foam hanging around from a year ago waiting to be used, and a new project, especially one requiring a new tool, would cheer me up.

So I got a hot knife. But not just a hot knife. No. I got the ultra-nifty, anything-you-could-possibly-dream-of-doing-with-a-hot-thingamajig model of hot knife (the Creative HotMarks tool by Walnut Hollow, pictured at top). Not only does it cut, it stamps, burnishes, heat-transfers, and all kinds of other scrapbooky good stuff like that. I don't really need all of those things but I didn't find the basic model of hot knife until after I checked out. It was in the locked cabinet by the shopping carts. So it was kind of too late to get that instead. And I liked the heat-transfer capability of the niftier model. So I took it home.

I'm delighted to report that the hot knife part of the crazy hot thingamajig works on 3 mm foam---not super-great, but waaayyy better than the utility knife I tried first as a comparison. Hooray! Creating lightweight, durable, colorful sculptural shapes without having to paint has become a possibility for me. But it will take practice.

Utility knife, stencil and 3 mm EVA foam. My comparison case.

The results: Choppy...

...and uneven. As compared to:

First cut with the hot knife. Still a little raggedy and uneven, but better, and so much easier!

One thing I learned that may save you some trouble if you try this out yourself is that, at least with 3 mm foam, it's hard to go all the way through the foam without first tracing the shape onto it with your stencil.

The stencil limits your use of the knife blade to just the tip. But tracing the shape with a pen or pencil first will leave marks on your finished pieces. The solution? A stylus!

A stylus is a small hand-held instrument with ball-tipped ends. It's great for poking around in small spaces, and, it turns out, for tracing shapes onto EVA foam. The foam is soft enough for the stylus to leave a visible mark. No ink or graphite needed.

When I traced my shapes first I was able to use more of the knife blade and came away with much cleaner edges. It's still tricky to get the shapes even on all sides, but cleaner edges make a big difference.

When all was said and done I had a bunch of nice-enough pieces with the promise of better ones to come. To flesh out the vision I used my practice pieces to make a little something.