Bobbins vs. Hembobs: Which Should You Use for Your Sewing Projects?
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What Are Bobbins & Hembobs?
To understand the differences between a bobbin and a hembob, it's important to know how a lockstitch sewing machine works. These machines use two threads: the upper thread and the lower thread. The lower thread is wound onto the bobbin. During stitching, the needle with the upper thread passes through the fabric, and a hook on the bobbin shuttle catches the upper thread, wrapping it around the bobbin. The threads then interlock, creating a lockstitch.
Bobbins vs. Hembobs: Key Differences
All lockstitch machines come with a bobbin case, located under the needle plate, which holds the bobbin. A bobbin is a small metal cylinder that holds the thread responsible for the bottom stitch. Before starting a new project, you'll need to wind the bobbin with thread from your spool and place it in the bobbin case.
So, how does a hembob differ from a bobbin? Simply put, a hembob is a pre-wound bobbin. Also known as belbobs or barbobs, hembobs are pre-filled with thread, ready for use in your machine. Many major thread manufacturers sell hembobs, and at Sailrite®, we offer them in sizes Tex 70 and Tex 90, made of UV-treated polyester thread. We stock hembobs in two sizes to fit different Sailrite machines:
- The Ultrafeed® uses a Class 15 or Style A bobbin
- The Fabricator® and Professional machines use a Style M bobbin
Each pack of 12 hembobs contains 25 to 58 yards of thread, depending on the size and thread thickness.
Benefits of Using Hembobs
Why should you consider using hembobs for your sewing projects? Here are a few benefits:
- Time-Saving: Hembobs eliminate the need to stop sewing and wind your own bobbins, making your workflow much more efficient.
- Smoother & More Uniform Winding: Hembobs are wound using professional machines, resulting in smoother, more consistent thread layers. This means more thread per bobbin, which reduces the frequency of changing bobbins during your projects.
- Longer Continuous Seams: Because hembobs don’t have flanges like traditional bobbins, they hold more thread. This allows for longer continuous seams, ideal for large projects that require a professional, polished finish.
Overfilled Hembobs? Here's How to Fix Them
Occasionally, you might encounter a hembob that's overfilled with thread. This can prevent your machine from stitching properly. If your machine won’t sew after inserting a hembob, don’t worry! Simply pull off about a foot of thread from the bobbin. This will remove any excess thread and glue, ensuring smooth operation when you start sewing.
How to Wind a Bobbin
If you prefer winding your own bobbins, follow these steps for the best results:
- Don’t Overfill: Fill the bobbin to about 80% of its outside diameter or leave about 1/16" from the edge. Overfilling can cause thread jams.
- Ensure Even Filling: Make sure the thread fills the bobbin evenly. If the thread accumulates unevenly, adjust the tension system on your sewing machine to correct it.
Check out our video below to see how to wind a bobbin correctly.
Bobbin & Hembob Tips for Better Sewing
- Match Thread Use: When sewing smaller projects, consider using a hembob in both the bobbin case and the spool pin for your upper thread. This ensures you run out of thread at the same time and can keep track of how much thread is left. Pro Tip: If you're facing tension issues with a hembob, reduce the tension on both the bobbin case and upper tension assembly to prevent knots or loose stitches.
- Pre-Wind Bobbins: For large projects, wind your bobbins ahead of time. This will save you from stopping to wind new bobbins mid-project.
- The Fabricator Can Wind While You Sew: The Fabricator Sewing Machine allows you to sew while winding bobbins at the same time. The Industrial Thread Stand holds two cones of thread — one for sewing and one for winding bobbins.
By using the right bobbins or hembobs for your projects, you'll save time, improve your stitching and make your sewing experience smoother overall.
