Resurfacing A Plastic Enrichment Ball

Boomer Balls, Jolly Balls, Wildlife Toy Box Balls - wherever you get them and whatever they call them they're the same basic thing; giant, hollow, plastic balls for our animals to use and abuse until they're too compromised to use as enrichment and then handed off to our education departments for docents to use as talking props.


Big cats and bears don't just break them, they wreck them. It'd be one thing if they just smashed them to bits like one of our Musk oxen did to a $200 ball one frosty morning, because we could always salvage the large pieces to cut small hides or feeders. No, the animals have to bite holes, gnaw, scratch, and gouge them up so badly that they become hard to clean and too sharp to use for animals with sensitive skin.

However, before we let these toys get to the condition of the one pictured above we can resurface them from time to time to extend their lifespan or repurpose them for another animal. That's because almost every vendor uses polypropylene to make them.

Polypropylene is a thermoplastic polymer (plastic) that's used in a lot of the products we use every day. Not just zoo animal toys, but cutting boards, synthetic rope, kids' play houses, syringes, and more. Heck, even the stickers on a Rubik's cube are polypropylene. It's durable, flexible, and resists high heat. That means we can take a torch to it and not worry about burning or even melting the plastic, but soften it.

Be sure to do this project in a well ventilated area and away from flammable materials! While we're not trying to burn up any of the plastic like kids around a campfire there still may be some fumes released. If you're not comfortable with the torch just catch one of your Operations folks to give you a quick tutorial and have a water source nearby and turned on as you work.

Here's a typical tiger claw mark that gouges open the plastic of the ball as if it were dough, when we couldn't leave a mark like that with a hammer and chisel. But one blip of the propane torch helps to erase almost all the micro-scratches that make this ball hazy looking and also begins to close the mouth of the scratch.

Another hit of the torch and the scratch gets more tight lipped and the surface really shines up as it gets even smoother.

Going over the whole ball you can go from something that had maybe two or three more uses in its lifespan to at least double that or something that can once again be used as a puzzle feeder for hoofstock without fear of them scratching up their tongues.

Any propane torch will do, but I love these push button electric start torches over the ol' flint spark style.

Start away from the ball and bring it to about an inch or two from the surface. Keep the tip moving so you're not blasting a small area. You want a large area to soften, not a small pinpoint to melt. You may see some discoloration start and that's a good sign to move to another area.

The plastic will be hot to the touch for some time so use that hose you have nearby to quench as you go so you can keep manipulating the toy as you work. If something just won't smooth out, file or sandpaper it off then torch it again. If you're really ambitious you can try and patch larger gashes with shavings from another part or another toy and do some plastic welding!