What knife to use for Foam Builds?

[Aiden26]

So I am making a cluster load of foam costumes for a saga I am doing. I was wonder what knife is the best and has blades that can last? I used a carpet blade before but it gets dull very fast. Any help is appreciated. Thanks!

 

[Ashuraa]

I tend to buy cheap single edge razor blades at Harbor Freight in packs of 100 for a couple of bucks. Another blade I tend to use is the blades that go into box cutters that are angled on each end. I know EVAkura tends to use a scalpel handle #3 and #11 Scalpel blades. he gets them online relatively cheaply as well. .

 

[AsthMattic]

Find a hot knife on Amazon. They are essentially soldering irons with x-acto knifes on the end. You can use the same blades you would in a normal x-acto knife.

The one I use isn't on Amazon anymore but this appears comparable: http://www.amazon.com/Xacto-X73780-...UTF8&qid=1420086351&sr=8-11&keywords=hotknife

I also highly recommend the video series Spacemeat has made; just look up Spacemeat the cosplay on YouTube. He shows the hot knife as well as the best techniques on cutting and making edges.

 

[Aiden26]

Find a hot knife on Amazon. They are essentially soldering irons with x-acto knifes on the end. You can use the same blades you would in a normal x-acto knife.

The one I use isn't on Amazon anymore but this appears comparable: http://www.amazon.com/Xacto-X73780-...UTF8&qid=1420086351&sr=8-11&keywords=hotknife

I also highly recommend the video series Spacemeat has made; just look up Spacemeat the cosplay on YouTube. He shows the hot knife as well as the best techniques on cutting and making edges.

What might be the result with using this knife? Do the edges burn? Also how often would I need to change the blade?

 

[EVAkura]

Unless you are dedicated to using a high quality respirator, I strongly discourage the use of a hot knife to cut EVA. The wisps of smoke that emanate from performing this action are highly carcinogenic. Safety is paramount.

Using a standard #11 blade (either scalpel, X-Acto, or generic) with the appropriate handle works excellent as long as you keep your blade sharp. I use a traditional "stick" style sharpener (the kind the butchers use) and will get weeks of use out of each blade with frequent sharpening.

 

[AsthMattic]

What might be the result with using this knife? Do the edges burn? Also how often would I need to change the blade?

The main result is a super smooth and effortless cut. The blade is long enough that the barrel doesn't touch the foam and therefore doesn't burn it. If you stick the blade into the foam it will burn it but if you keep pressure along the cut it just glides right through. EVAkura does make a great point about the potential of burning foam, so always make sure you are using the method in a extremely well ventilated area and/or with a respirator. I don't change blades very often, it just depends on how picky you are about the ease of cutting. My girlfriend changes them all the time but I really never do... just preference. But the good news is that they accept standard x-acto blades so they are relatively inexpensive.

 

[CrazyIvanVI]

I second using the scalpel and #11 blades. I got a set of 100 online for less than $15. I used to use a utility knife until I bought the scalpel set on a whim. It hurts me a little bit to say I'm not sure where my utility knife is anymore.