Can Lid

thingiverse

The low-cost molded plastic food can closures are crafted under extremely tight budget constraints, inevitably resulting in fractures and tears, especially when frequently exposed to refrigerator temperatures and scalding hot water. A friend with a small dog that only required half a can of food per meal quickly went through several and asked if I could design a more durable alternative capable of withstanding heavy use. This design is as straightforward as it gets and was my first attempt at using Tinkercad, but it does its job remarkably well. The STL file is based on the original, which I printed in PLA (the only material available to me). As a result, it had to be slightly loose to snap onto the metal roll-over rim of the can without breaking. Despite this, it functioned perfectly and if the rattling noise becomes bothersome, you can simply paint the inside with epoxy or latex adhesive. However, please note that this is not suitable for long-term food storage, but a day or two would pose no significant risk of contamination. Of course, refrain from placing PLA ones in the dishwasher! Unless you appreciate modern art! Apparently, my friend forgot that PLA has a glass transition temperature of 55°C, which is lower than the 70°C dishwasher temperature... So the next batch were produced using my brand new roll of Rigid.Ink orange PETG. To print in PETG (as my more recent designs have been), you'll need to make a couple of adjustments in the slicer. First, scale down to 99% - as PETG is slightly springy, a tighter fit works just fine. I tried one at 98% and it worked but took considerable effort to press onto the can. Second, use a higher temperature than usual - detail is less important than achieving a smooth upper surface (the lower/inside surface when in use) - I switch from my regular 230°C to 235. Finally, set to provide at least 0.4mm thick top and bottom layers. Infill is barely utilized so anything over 20% will work just fine unless you're extremely particular about a glass-smooth surface that only your half-used tin of dog food will ever encounter. I always recommend PETG for this application simply because you can achieve a tighter fit without it exploding into pieces. Plus, in translucent orange, they're the most visually appealing half-used-dog-food-tin covers around!