Fly Trap

Come summer, the flies around our place go from “mildly annoying” to “full-time unpaid roommates.” The worst offenders are the shiny green ones and the big blowflies — the kind that sound like tiny helicopters and behave like they pay rent.

Fun (and slightly horrifying) fact: Australia is home to about 30,000 fly species. Yep. Thirty. Thousand.

Good news: we’re “only” fighting about 4–5 of them. So… manageable. 😅

We’ve also got horses nearby and a small abattoir in the area, which basically means the local flies have a strong food scene. If you think you can step outside without letting them in, think again. These geniuses fly in at ground level so you don’t even see them, then they loiter at the door like they’re waiting for you to open a VIP entrance.

There are heaps of fly traps and DIY suggestions out there — this is the combo that’s been reliably gross (aka: it works).

The setup

I designed and printed a funnel-style fly trap that fits on a recycled jar. Since the traps go outside, it's best to us PETG.

Jar

• Aldi pickle jar (350g) works perfectly (hello, snack + free container).
• If you’re in the US, you’ll likely want a 12 oz jar.
• In the UK, the same Aldi 350g jars should do the job.

Bait

• Australia: EnviroSafe Fly Trap powder refills (sold at Bunnings, roughly $10 for 3 sachets).

   

  • One 350g jar uses about ½ a sachet.
  • Top up with water but no more than ⅓ full, and when it’s full of bodies… empty, rinse, refill, repeat.

   

• UK option: Zero In XL Fly Catcher Bait works well.

Why this version?

The commercial plastic traps work… but they also absorb the smell of doom and eventually become a single-use stink grenade. Then you have to toss them and buy another one, which gets expensive fast.

This version uses glass, so it doesn’t “marinate” the stench the same way — and if you ever decide you do want to ditch the glass… just buy another jar of pickles, eat the pickles, and you’re back in business. Sustainability, but make it delicious.

The Fusion 360 Source file is available for you on my Patreon if you want to adjust the trap for your needs or just want to see how I made it.

Happy printing — and may your summer be slightly less buzzy. 🪰💀