Tips for Zippers in Leatherworking

Last week, I posted about the idea of (tsudzukete) “keep going.” When sharpening knives for leatherworking, a common mistake is to stop too early, resulting in your knife never getting sharp enough. Knowing when it’s done is why I still teach in-person courses. It’s an eye-opening experience to cut with a freshly sharpened knife. New students often have never used one, which is why I keep a big box of band-aids nearby. Learning to ease up can be a big adjustment if you’re used to pushing and struggling to cut.

Working with zippers can be the same. New students wonder, “What’s the big deal? It’s just a zipper.” You don’t realize how unruly they can be until you install some zippers into your project. They can twist, misalign, or be too tight, or you can even install the pulls the wrong way on the zipper. I removed an old zipper tape and realized I had put two pulls on a one-way zipper. One worked fine, and the other, facing the wrong way, struggled to open.

It’s not until you see, or even better, experience putting in a zipper correctly that you can see how much you can dial in the fit. You can set the tape so that the teeth are centered on the opening, adjust the length so that it’s not too tight or loose, especially around curves and corners, add custom pulls to customize your designs, and you can install the pull in the right direction :).

We’ll soon launch our new online leathercraft course on making a zippered wallet. Before we do that, let’s review some basics about zippers for leatherworking, including a few important tips to help you install them more easily.

Zipper Material and Types

I want to narrow the scope of this leatherworking tutorial by material and type. I exclusively use metal zippers when making leather goods in my leatherworking practice. There are other types of zippers, namely coil, plastic, and invisible, but I don’t use these often. These types are commonly used in fabric and apparel. I’ll, instead, focus on what I typically use for leather projects, and perhaps when I start making leather jackets, I’ll add more tutorials for these other zipper types.

The Parts of a Zipper

A zipper is composed of several parts, and there are several ways to construct a zipper. The main parts of a zipper are the:

• Tape – these are the fabric on the two sides of the zipper.
• Teeth – the small metal pieces that interlock.
• Chain – all of the teeth together form the chain of the zipper.
• Pulls – one or more parts that slide up and down the chain to open and close the zipper. Pulls are Y-shaped, separating the zipper at the top and closing the zipper at the bottom.
• Stops – there is a bottom stop that prevents the pull from lowering further. The top stop prevents the zipper pull from rising further.

There is an excellent Wikipedia entry on zippers, which goes over the parts in more detail. Today, I’ll cover the main components and what to consider when picking zippers for your next leatherworking project.

Pre-Cut and Continuous Chain

There are pre-cut zippers with stops and pulls already installed. Most fabric stores carry pre-cut zippers in standard lengths like 5, 9, 12, and 24 inches. Continuous chain zippers are cut to custom lengths. You can usually get them by the yard, cut them to your desired size, and install stops and pulls to fit your project.

Closed, Opened, and Separating Zippers

Zippers can be closed or open. Closed zippers have a stop on either end. Open or separating zippers are found on items like jackets where the two sides of the zipper come apart down the middle of the coat so you can put it on. At the top are top stops, and at the bottom end of the zipper, there is a pin on one tape end and a box on the other. You put them together to zip up your jacket. Most of these types of zippers are one-way and have a single pull on them. Some are two-way, allowing you to open the middle with the top and bottom ends closed. There is also a third rarer variation where there are pins on all four ends of the tape, a two-way open zipper with two pulls where you can open and close the top, bottom, middle, or all three!

I have not seen separate boxes and pins you can install onto a continuous chain zipper. These components are installed when the zipper is manufactured, and I have only seen open zippers sold at pre-fixed lengths.

One-way vs. Two-Way Zipper Tape

A metal zipper tape can be installed with either side facing up. There is usually no up or down, so you can lay down a zipper and flip it over, and it doesn’t matter. Once you add the pulls, the ‘up’ side is the one where you can grab the pull, and it is installed facing the outside of the piece.

There is a direction, however, with one-way tape. As its name implies, a one-way zipper tape can only open in one direction. The way to tell is by the teeth. There is a more prominent spike on the teeth of one-way zippers. The spikes should point towards the top stops, and the pull should be installed with the Y-shape facing upright. One-way zippers are usually a little cheaper than their two-way counterparts.

In contrast, a two-way zipper tape opens in either direction, and you can set the pull facing either way. You can also install two pulls facing opposite ways. This is my preferred type of zipper because it is the most flexible. If you’re unsure whether a zipper is two-way, put in the pulls and see whether it opens smoothly. A two-way zipper will open very easily in both directions. A one-way zipper will be very stiff when opening the wrong way or will not open at all unless the pull is put on in the right direction.

Sizes

Zippers come in a variety of sizes. The smaller the number, the smaller the teeth, the pulls, and the narrower the tape. Sizes can vary between manufacturers. Smaller tape is best suited for smaller items with relatively low stress, while larger tapes are best for large items with heavy use.

Zipper Sizes

You typically select the size of the zipper based on the size of the opening and the piece. For a small zippered wallet, choose size 3 or 5. Size 5 works great for medium projects like large, long wallets or handbags. For luggage or large bags, you should select sizes 8 or 10.

At Fine Leatherworking, we sell two-way continuous chain zippers, which offer a lot of flexibility for your projects. We carry size 5, an excellent choice for medium-sized projects like handbags. Size 5 can also work for slightly smaller projects like long wallets or larger bags, like totes. We have a few popular colors in size 3, the next most commonly used size.

Install Top and Bottom Stops Appropriately

The top stops are installed in pairs, preventing the pull from rising further. There is one on each side of the tape, and they fit into the top of the Y-shape on the pull.

Stops are placed according to the pull that touches them. The bottom stop spans both sides of the top and stops the pull from lowering. In the stopped position, the pull rests against the bottom stop.

If you have one pull on the zipper, install the bottom stop at the bottom, and the top stops at the top. Orient the stops according to the pull. The bottom stop goes below the ‘Y’ of the pull where the zipper closes, and the top stops go above the ‘Y’ where the zipper opens. If you add two pulls, install two bottom stops. The pulls usually face each other and open as they travel apart.

Some people install two bottom stops, even with one pull. This is ok but not as clean as adding a top and a bottom. Abiding by this principle of ‘keep going,’ you can further refine your construction so that when a zipper is closed, it looks closed.

Below is a picture of a bottom stop installed against the top of the pull. What do you notice?

The bottom stop pulls together the end of the zipper, but the top of the pull fights it because it is setting the zipper to the open position. This leaves a small gap at this end. Additionally, you can see the tape pucker from the stress.

Here, the top stops are installed above the zipper pull ‘Y’. The stops fit into the pull, and the closed zipper is nice and flat.

Go Further with Zippers for Leathercrafting

Just like sharpening, there is a basic level of using zippers in leather goods, and then ever-deepening levels of refining how to install, size, and best use them. Our upcoming course will show you how to measure, cut, prepare, and install zippers for a zippered wallet. Stay tuned for more tips and the course.