Remix of an amazing bottle cap by 3D-Academy. I modified it so you can insert a standard bicycle valve stem. This way you can attach a bicycle pump to the bottle and pressurize it. Anyone who is familiar with using PET to make printer filament will know what this is for (applying heat to the bottle while it’s pressurized in order to make the bottle smooth and easier to cut into a uniform size ribbon for use with a PolyFormer type machine). The bearing that is shown with mine is for use with another project I am working on so you can easily rotate the bottle while using a heat gun. more to come with that project soon.
I found that if you leave a little bit of the inner tube around the valve stem you can get it to fit perfectly inside the bottle cap and don’t even need to glue it into place. Tightening the cap will form an airtight seal.
The author remixed this model.