SINOMALL Small Simple Easy Battery Craft Hot Knife Styrofoam Cutter Hot Wire Foam Cutter Cutting Machine Cuts Foam KT Board Wax for Children Learning

Pretty simple circuit with wire that quickly heats up as a button/connection is made. Dimensions are listed and it's true to those/the images. Takes 2x C type batteries which are very simple to plug in. Needed it to cut some foam and at least with that foam (fairly firm) it's done the job well. Not extensively used yet but works for some fairly precise bits as well as straight runs. The wire that does the cutting can bend a little with pressure but it's easy enough to mitigate that and it's no surprise.

does the job but could have been designed for 9 volt battery so I modified it

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