Materials
Cordura
One of the bread-and-butter materials I use. Though, to clarify, Cordura is just a brand name that most folks are familiar with, and while I use that, I also use other similar varieties of rugged nylon in varying weights, depending on how much wear it'll take. It's tough, abrasion resistant, durable, and great for exterior-facing fabrics that'll be facing a lot of wear. It also usually has a water-resistant coating on the inner to help keep water out, though this tends to wear off over time and so I'll usually pair it with a liner fabric like vinyl or a coated ripstop nylon which will also be water-resistant.
I generally go with 1680D ballistic nylon for backpack bottoms, and anywhere between 400-1000D for sides, or pouches which won't face as much wear but still need to be tough.
X-Pac
A decently abrasion-resistant fabric which is a laminate of multiple layers (including a waterproof one), as opposed to Cordura which only has a waterproof coating applied to the inner. This means a rugged nylon or polyester exterior, a waterproof film, and often a very light polyester inner to protect the film. Thanks to it being inherently waterproof it doesn't necessarily need a liner fabric (though I do pair it with ripstop or oxford to reduce inner wear) and makes a great lightweight option for frame bags, saddle bags, and less wear-prone parts of bags and pouches.
I usually stick to the mid-weight variants (VX15 or VX21) which sit a bit below 500D Cordura in terms of durability. If it's something you'd want for a custom though, I'm happy to order it!
Vinyl
My go-to liner fabric. Sometimes referred to as "truck tarp" or "PVC coated polyester" depending on its construction. It's water-resistant, tough, and while heavier than something like ripstop nylon, it holds its shape well and gives bags structure when needed. Being a liner fabric, I generally use brighter colours to help make things easier to see inside bags/pouches.
18oz is my go-to for most everything for its balance of weight and it holding its shape over time.
Ripstop
My second liner fabric of choice. Usually nylon, sometimes polyester. Generally has a water-resistant coating, only slightly less wear-resistant than vinyl but much lighter. While it doesn't hold its structure as well, it's great for projects where weight is a concern.
Merino Wool
My absolute favourite wearable fabric for the balance it offers of breathability, insulation, ability to dry quickly, and most importantly, non-stinkiness. Being naturally anti-microbial means it doesn't get the same funk polyester does after a while, and it's much more environmentally friendly than polyester (which, much as I like to use it, is just plastic).
Magnetic Fasteners
You'll see a lot of Fidlock and Woojin Plastics Magic Buckle hardware on a lot of the stuff I make. It's a great alternative closure where hook/loop (Velcro) might be but it doesn't wear out like hook/loop does...and it's just cooler. In some cases I'll still use hook/loop or regular side-release clip style buckles for security, weight, or cost saving, but magnets are my favourite and can be undone/done with much less worry of wear over time.
Upcycled Materials
Sometimes folks stop using gear of theirs, or can no longer use it, for one reason or another. In many cases it may still be in good condition save for some flaws, be it a key point that's broken or undesirable cosmetic damage. Instead of having these products simply get thrown out, I prefer to take what is still usable from them and give them new life in new gear!
Any of the fabric or notions I salvage from old gear I inspect to make sure is still functional, even if it shows signs of wear or non-uniformity. In the case of bags/pouches I make sure fabric is still water-resistant, durable, and structurally sound where it needs to be; in the case of clothing I make sure fabric is free of tears or rips that may be exacerbated too early on by use.