Variable size Canning Funnel

This Design

There are literally dozens of designs for Mason Jar canning funnels. So what makes this one special?

• Most designs I've encountered are just a simple cone into a cylinder. I've built this with a nice radius in the throat. A nod to chickenchuck040 for the arc module (see attribution).

• Mason Jars and their lids are expensive where I live. So it's cheaper to collect commercial jars and purchase replacement lids. The sample STLs I've included are for the most commonly available jars. 67mm & 57mm throats.

• Because commercial jar have a large range of throat sizes, my design is also very easily resizable.

Using The Design

The Canning Funnel was designed in OpenSCAD. It is a "customiser" that includes two variables used to adjust the size of the funnel to suite different commercial jar throat diameters:

JarThroatSize = 57;
JarThroatDepth = 15;

The "JarThroatSize" defines the outer diameter of the throat. The "JarThroatDepth" defines how far down into the jar the throat extends. If not immediately obvious, the advantage is that the design automatically adjust the size of all the other funnel components.

Bonus Features

The design also includes a simple handle. I chose not to print the handle because I wanted to stack my funnels inside each other. But yes, there is an EnableHandle true/false switch to enable it. But a word of warning. The handle was a whimsicle extra. It works for the above throat sizes, but with very small and very large it breaks.

The EnableHandle does not appear to get picked up in the Customizer?

About Canning

• I never recycle commercial jar lids. I highly recommend that you should not either. Commercial, and Mason, lids are designed for single use only. Re-use of lids risks air leaks and contamination.

• Yes, the commercial jars are intended as single use. So technically not as robust as the Mason ones. I do a lot of high pressure / high temperature canning. And I've only had a couple of breakages over the years, and they are free to replace.

• If you are curious where I source my commercial lids, I'm happy to pass on the URL.