Fruit Fly Trap Jar Lid

by AlexEnglish, published

Fruit Fly Trap Jar Lid by AlexEnglish Mar 16, 2012

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13031Views 2920Downloads Found in Kitchen & Dining
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This is a fruit fly trap lid that screws on to a normal canning / mason jar.

This is based on this canning jar lid: http://www.thingiverse.com/thing:19105

The fly trap lid pictured was printed with a low, draft resolution on a Mosaic with ProtoParadigm Red PLA.

This thing is a part of a collection of things featured in this post: http://www.protoparadigm.com/blog/2012/08/what-to-do-with-a-3d-printer-make-canning-jar-accessories/


Download whichever you need and print it. There is a regular, and a wide-mouth version available.

After printing, put some bait in a canning jar and screw the lid on. This bait can be pieces of fruit, fruit juice, or anything else that will attract fruit flies. As luck would have it, I haven't had any fruit flies around since I finished this (not that I'm complaining), so I haven't had a chance to test it, but I've had good luck with cruder traps of similar design in the past. Apparently a mix of some fruit juice with just a little bit of vinegar in it is a decent bait.

Place the baited trap near where you have fruit flies. They should enter through the hole at the end of the inverted cone, and will be unable to escape.

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Fruit Fly Trap Jar Lid by AlexEnglish is licensed under the GNU - GPL license.

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I was talking with somebody about a lid that would fit onto a canning jar to trap fruit flies... and then I stumbled onto your design. It's perfect! I've been using a glass with a taped on paper cone: not the most pleasant to look at.

The only problem is that I don't have a 3D Printer. Is there any way you could print some of these for me and ship them to me? I'm happy to pay you securely through PayPal.

Please let me know.

Thanks a bunch for your consideration!


For some reason the scad file fails for me, and i am not familiar with scad, can you make one with an approx 15mm opening? our problem here is wasps.

I made one and it works great! I have captured many fruit flies. I didn't have a canning jar on hand, but I found a clear plastic jar in my cupboard with the same size threads -- can't remember what came in that jar originally. For bait, I found that fruit flies love red wine. I discovered that when I left a glass of red wine on the coffee table for a very short time and came back and found two drunk fruit flies doing the backstroke in my wine. So I use maybe half a teaspoon or so in the jar. If I have a banana or a peach handy I put a chunk of banana or peach skin in also. My fruit flies go out in gourmet fashion! Peaches and red wine sounds like a great way to die to me!

Any chance you could upload a Makerbot-friendly file? When I use ReplicatorG, I feel way over my head configuring the infill and shells. I am new to all of this.

Thank you for your consideration!

You have no fruit flies after you made the trap? IT WORKED!

Seriously, though, what tool did you use to make this? I love the threads on the inside of the lid. It also makes pretty music when printing.

Oh, also, I didn't mean to be deceptive, I've updated the text of the thing to be clearer that I haven't had a chance to test this yet because I haven't had any fruit flies, but traps that work by the same means have worked well for me in the past.

I designed this in openscad. I try to take a somewhat modular approach to design, so this also depends on http://www.thingiverse.com/thing:19105http://www.thingiverse.com/thi... which is the lid with the threads. The threads were designed from caliper measurements, and implemented with this thread library for openscad: http://www.thingiverse.com/thing:8793http://www.thingiverse.com/thi...

I'm glad you like it. :)

Canning Jar Lids
Screw Library
by syvwlch

Nice! I have used vinegar, a drop of syrup and a drop of dishsoap to remove the surface tension seem quite effective. I guess one could smeer some syrup around the middle of cone to get some to stick around incase of an Houdini.

That's a great idea, putting syrup on the under-side of the cone. Thanks for the input regarding the dishsoap too.