At an outdoor festival, my sons and I saw a group of teens play-fighting with padded swords. That looked like a lot of fun, so we tried making our own. It was remarkably easy and inexpensive — each sword costs about $4.
The foam we chose has adhesive along the slit, but a few wraps of duct tape every foot or so will ensure that it doesn’t split open. Some people wrap the whole thing in duct tape. Covering the handle with duct tape is also an option.
We battle using Monty Python’s “Black Knight” rules: a chop to your opponent’s arm or leg disables it; keep fighting until one of you has no limbs left. In the photo, Sir Christopher has lost both legs and King Toma has lost an arm.
It’s great, silly fun to fight while hopping on one leg or gripping the sword between your knees because you’ve lost both arms. Plus, the low mass of the poles and the thick padding make sparring fairly safe.