Most canvas bags are not made of waxed canvas. So using waxed canvas is itself an upgrade. And like any fine craft, there is art and science involved. We use only Martexin Original Wax canvas, an American heritage canvas supplier that's been around since 1838. Here's some background directly from the company:
"Martexin Original Wax is a cotton-based fabric impregnated with Martin Dyeing & Finishing Company's proprietary formula that gives the fabric lifelong resistance to inclement weather, while cotton fibers allow it to breathe. As the fabric ages, it develops a well-worn and comfortable patina. The Martexin formula consists of food and pharmaceutical grade waxes, and is completely non-hazardous. The Martin family has been involved in dyeing and finishing of textiles in the United States since 1838. The method, application, and formulation of their waxing process are tightly guarded family secrets, which have been passed down through father to son for seven generations. Martexin Original Wax is environmentally friendly and is available domestically from the same family that has supplied the United States market for over 170 years."
This stuff is truly amazing. We actually invest more in this canvas than some bag makers spend on their leather. So there you have it. Is there any doubt you're getting the "good stuff"?