Tennis Ball Mortar
Scouts create mortars using three Pringles cans, duct tape and lighter fluid.
See attached sheet, and here's a video of what not to do: https://www.youtube.com/watch?v=mk_caZPEcrQ
See attached sheet.
In terms of safety, recommended that you use age restrictions around the firing element. Also gloves and goggles are a must, have water on standby, and earmuffs could be a good idea.
A large open field is also a must, but the building of the mortars is perhaps better indoors due to sturdier work surfaces.
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