If you love shopping at Costco, you'll appreciate this 3D-printed shopping cart tray. It's designed to securely clip onto the newer Costco shopping carts (cart measurements taken in northern California) and give you a space to set down your Costco hotdog, soft drink and free samples. In addition to the tray and cup holder, there's a space for an alligator clip to hold your Costco membership card, receipt or shopping list. 

Note: This is my own design but was originally inspired by TheIdeaDad. Many thanks to him for the clever idea and giving his OK to share my iteration.

I purchased “Metal Wire Alligator Clamp Long-Tailed Alligator Iron Clip Clasp for DIY Card Clip Holder 6 inch (150mm)” from Amazon.

I used super glue (cyanoacrylate) to attach the phone holder to the tray.

Print recommendations:

• 0.20 mm layer height

• 3 walls

• Infill density 20% (I used gyroid)

• Overhang speed - 10 mm/s

• Print with support (I used tree support - strong)

  • Top Z Distance - .27mm

For  a commercial license to sell my 3D prints - https://www.patreon.com/c/kevlar_777_/membership