Making a Composite Part From A Foam Plug

I was recently asked how to make a part that didn’t exist. Once again I will lean on our friends over at for a video tutorial on how to make a part from nothing. Now they do go a little overboard for most applications, but since they are making an air box that was designed with CAD software, very accurate dimensions are a little more important in their case. If you are just making a one off air scoop for example, that isn’t designed by a computer, sanding down foam to a rough shape that looks about right will work most of the time. Also, I will add that you don’t need polyurethane foam. Polystyrene foam can be used, but you must use epoxy to coat it to give it a “shell” to then smooth out and polish. Polystyrene foam is what you can find at Home Depot or Lowes, so its more easily available to most people. So just be sure to use the correct chemicals on the correct foams. Otherwise, the sanding and shaping, and molding steps are essentially the same. You can also start to realize how a background in the body work industry can really start to help out. This is also a 3 part video tutorial and I’ll get the other ups over the next few days with some of my comments on them. Enjoy!