Where to buy foam?

If you are in the US, look for an insulation supply house. Make sure to ask for virgin foam. The other kind has whats called regrind and is hard spots in the foam. If you can't find it locally, start here:

Thanks for the info - also thanks to Ray A. Gareau, who emailed me.

Happy Holidays!

Ken

You have to be careful with DIY foam. Much of it is full of regrind. Quick way to tell is run your hand over the surface. If you feel hard, sharp spots, don't use it. The regrind is pieces of recycled foam that is mixed in as filler. It is harder than the rest of the foam and will cause your wire to drag or go around it. It will also be nearly impossible to sand to a smooth finish.