Sewing Blog

Sewing Magnetic Snaps for Perfect Bag Closures

A simple bag is great project for learning how to sew for beginners. One essential technique you need to sew any bag is knowing how to give the bag a closure. And, the use of magnetic snaps in bag making is a very simple and effective way to add top closures or flaps.

There are two different kinds of magnetic snaps: invisible and traditional. In this post, I'll walk you through how to install both methods — you can adapt these into many different bags!

Invisible Magnetic Snaps

Installing an invisible magnetic snap

Invisible magnetic snaps come in several different sizes; I like to use the 3/4" (or 18mm) size for bags. The round magnet is enclosed in a clear vinyl sleeve. The sleeve will assist you in sewing the magnet directly to your fabric or interfacing (I prefer to sew mine to interfacing).

Marking the magnetic sides of the invisible snaps.

Step 1:

The most important thing to remember when working with invisible magnetic snaps is that one side of the magnet will repel against the other, and one side will attract.

Before beginning, I like to mark with a pen or marker which side of the magnets will repel. I'm in the habit of using the letters 'A' and 'B' to mark the attracting side of the magnets because I often will need more than one pair of magnets to make a bag, and this way I can keep track of my pairs.

Marking the interfacing for snap placement.

Step 2:

I like to attach my invisible magnetic snap to the respective interfacing before I fuse or baste the interfacing to the fabric. In my example, I am showing By Annie's Soft and Stable interfacing for a flap piece.

  • First, with an invisible fabric marker, mark the snap placement on the flap according to the pattern that you are working with (I often like to place my snaps centered, and up 1-1/2" from the bottom edge of the flap, as I've done in the example here).
  • Place the snap directly on top of the mark that you made (for my flap example, I am placing the marked magnetic side face down).
Stitching the invisible magnetic snap in place.

Step 3:

Next, use either a tight zig-zag stitch on your sewing machine or two rows of double stitches, to sew all along the outer edge of the vinyl sleeve using a 1/8" seam allowance.

Since the snap will likely be opening and closing many times and putting stress on that vinyl sleeve, you want to make sure that the snap is attached well. In my example here, I've used the two rows of double stitches.

Attaching the fabric to the interfacing.Step 4:

Now all that remains is to fuse or baste your fabric to the interfacing that you just attached the magnetic snap to. I am using Soft and Stable, which is a sew-in interfacing, and so I will baste the fabric to the outer edge of my fabric using a 1/8" seam allowance.

In my example, I am basting the fabric to the opposite side that I have attached my snap, as I want the magnet to go through that layer of interfacing before it touches the other magnet on the main panel of the bag that I'm working on (I use really strong magnets!).

Invisible magnetic snaps are that easy to attach! Now you will just repeat the process to install the remaining half of the magnetic snap onto the front of your bag that the snap will be attaching to. If the pattern you are using does not call for invisible magnetic snaps, you can substitute them in, just be sure to be mindful of which side of the fabric or interfacing that the magnetized side of the snap needs to be facing.

Sew Sweetness Petrillo Bag

Several of my bag patterns call for the use of invisible magnetic snaps, and the most popular of those is my Petrillo Bag sewing pattern (there's a magnetic snap in the gathered flap!).

Get the Petrillo Bag sewing pattern here.

Traditional magnetic snap

Traditional Magnetic SnapsTraditional magnetic snaps are the most widely available. You will notice that these magnetic snaps have what is referred to as a 'male' and a 'female' half. The male half is usually thinner and has a 'nub' in the middle, and the female half has a little recess in the center.

I usually like to use the male portion on the flap part of the bag, as the flap is usually smaller than the body of the bag and I think this pairs nicely with the smaller half of the magnetic snap.

Besides the two halves, traditional magnetic snaps sometimes come with two metal washers; the washers will usually have a circle cut-out in the center and a rectangular cut-out on either side. If your magnetic snaps do not have these washers, don't stress, this is just optional (but nice to have!).

Using the washer to mark snap placement.

Step 1:

To get started installing traditional magnetic snaps, it's important to have all the fabric pieces for your bag cut out and fused or basted to interfacing as directed in the pattern that you are using. I like to use my invisible fabric marker to mark the prong placement for the snaps (you can either use the prongs themselves to mark placement, or you can use that handy washer if it came with your snaps).

Often, snaps will be installed either 1" or 1-1/2" above the bottom edge of a flap, or down 1-1/2" from the top edge of a lining (if you're installing the snaps as a closure for your bag).

Using seam ripper to make small slits in the fabric/interfacing.

Step 2:

After prong placement has been marked, get out your seam ripper and use it to make tiny slits the length of the marks that you made. Start small, as you can always make the hole bigger if need be. I like to follow up the slits that I've made with a dab of seam sealant, as this helps stabilize the fabric against the snap being opened and closed many times over the life of the bag.

Next, insert the snap through the right side of the fabric.

Inserting the snap through the fabric/interfacing.

Step 3:

Flip to the wrong side of the fabric (the interfaced side). If you have a washer, slide that onto the snap next. If your interfaced fabric is very thin (for example, if you are inserting the snaps into lining fabric), I sometimes find it helpful to also slide a 1-1/2" x 1-1/2" scrap of batting or interfacing onto the prongs on the wrong side of the fabric before inserting the washer.

This helps avoid the snap tearing through the fabric eventually. You can see in my example how I have used that 1-1/2" scrap.

Opening the prongs on the snap outward.

Step 4:

After you've done all that, the last step is to open the prongs of the snap outward. You can do this with snap pliers or by leaning some other heavy object against the prong of the snap (I have a plastic sewing table, and I like to lean my prongs against the table to quickly open them outward).

The installed traditional magnetic snap.This is what the snap should look like when finished.

All that's left is to insert the remaining half of the traditional magnetic snap onto the body of your bag (or wherever you need that other half to go).

Sew Sweetness Rockstar Bag

Many bag patterns utilize traditional magnetic can see one in action in the flap in my Rockstar Bag!

Get the Rockstar Bag sewing pattern here.

Invisible magnetic snaps and traditional magnetic snaps are very useful and great to add into any bag. I hope you've enjoyed this tutorial! Which kind of snap would you like to add to your next bag?

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