This thing is easily built and cuts all types of Styrofoam ( Blocks & Sheets ) into any shape or form desired.    I designed my system to have 2 - Wands, meaning a "Large Bow" = for cutting large hulls, plus a smaller "Hand Wand" for smaller cutting tasks.    Like - for example, carving a stern - tunnel into the foam core of a models hull.    (( WARNING .... This Is Not A Toy! ))  DANGEROUS TO OPERATE!!   The Hot Wire gets - RED HOT and can easily - Burn You .... So be careful using this device and be sure any helpers - assisting you, are aware of the dangers too!

HOT WIRE .... Parts List -

#1 ... Ac or Dc - Model Train Transformer  ( 12 to 18 volts  output at  2 - 4 Amps. )  Most any train transformer will do, including similar Power Transformers with variable Ac or Dc - outputs.  Purchased or Scrapped from your parts, that meet required Voltage & Amps.

#2 ... Dowel Wood - Rods =  ( Handle & Bow ) making parts of 1/4" &  3/4" Dia. Rods    NOTE ... Make the Bow and Hand Wand to the widths you require, to cut any size foam.    Usually a nichrome wire stretched between the bow - ends, that's 2 1/2 feet wide - at most.    Works fine for most any job you'll use this system for.    As for the Hand Wand, it should be a U-shaped - short piece of nichrome wire, about 4 inches in length = between the forks of the wand.    Then before use, shape the wire to desired shapes for carving jobs, then turn the power - On and gently start carving.

#3 ... Nichrome Wire Sources = Hobby Shops or Hobby Suppliers =  A resistor wire that heats up, to cut or melt Styrofoam.

#4 ... Two Scrap pieces of Brass Tubing, used to make - heat insulators to avoid the wood dowel rods from being burned by the nichrome wire.

    INSTRUCTIONS FOR USE .......    Set your Transformers - voltage settings, at the lowest voltage setting - First.    Then turn the system - On.    Slowly increase the voltage until the "Nichrome Wire" starts to smoke and heat up.    Testing the heat settings on a piece of scrap foam - First, before you start cutting anything,  adjusting the voltage setting accordingly.    WARNING .... Never set the voltage higher  than is needed to cut your foam, Slow & Smoothly.   The wire can be easily - Burn Out and will break apart and easily injure you or someone else!