Picking out the right gammill bobbins is one of those small decisions that can either make your quilting day a breeze or a total nightmare. If you've spent any time behind a longarm, you know that these machines are absolute workhorses, but they can also be a bit temperamental if you don't give them exactly what they want. It's not just about finding something that fits in the case; it's about ensuring the tension is consistent from the first inch of the quilt to the very last.
Most Gammill machines are built to use the Large M-Style bobbin. These things are significantly bigger than what you'd find in a standard domestic sewing machine, which is a lifesaver when you're working on a massive king-sized quilt. Nobody wants to stop and change their thread every ten minutes. But even though they're bigger, they aren't all created equal. You have to think about the material, the weight, and whether you want to spend your time winding them yourself or just popping in a pre-wound and getting straight to the fun part.
Why Quality Actually Matters
It's tempting to hop online and buy the cheapest bulk pack of metal bobbins you can find. I get it—quilting is an expensive hobby, and we're always looking for ways to save a few bucks for more fabric. But honestly, cheap bobbins are usually a trap. If they're even slightly warped or if the edges have tiny burrs on them, your thread is going to snag.
When you're running a Gammill at high speeds, that tiny snag becomes a major problem. It leads to thread breaks, skipped stitches, and that dreaded "eyelashing" on the back of your quilt. High-quality gammill bobbins are usually made from aluminum or high-grade steel. Aluminum is popular because it's lightweight, which means it has less "inertia." Basically, when you stop stitching, the bobbin stops spinning faster, which prevents the thread from backlashing and tangling inside the case.
The Great Pre-wound Debate
If you walk into any quilting guild meeting and ask about pre-wound bobbins versus winding your own, you're going to get some very strong opinions. It's almost like asking about Ford vs. Chevy.
A lot of Gammill owners swear by pre-wound bobbins. The main reason is consistency. When a machine winds a bobbin at the factory, it applies perfectly even tension throughout the entire spool. When we wind them at home on our little side-winders, we sometimes get "squishy" bobbins where the thread is tighter in some spots and looser in others. That variance can mess with your stitch quality.
Then there's the issue of yardage. Pre-wounds are usually wound much tighter and more efficiently than what we can do ourselves, meaning you get way more thread on a single bobbin. If you hate stopping mid-row, pre-wounds are your best friend. Brands like Fil-Tec (especially the Magna-Glide line) are huge in the Gammill community because they have a magnetic core. This magnet helps the bobbin stay seated in the case and prevents it from spinning freely when you slow down or stop, which solves the backlash problem entirely.
On the flip side, winding your own bobbins gives you total control over the thread type. If you have a specific variegated thread or a silk thread that doesn't come in a pre-wound format, you're going to be winding. If you go this route, just make sure your metal gammill bobbins are in perfect shape. Give them a quick roll on a flat table; if they wobble, toss them.
Dialing in the Tension
Getting your bobbin tension right is probably 80% of the battle when it comes to a beautiful stitch. Most people are terrified of touching their bobbin case screw, but you shouldn't be! It's there for a reason.
The "drop test" is the classic way to check things. You put your loaded bobbin into the case, hold the thread tail, and see if the case drops when you give it a little jiggle. For a Gammill, you want it to slide down slowly and smoothly—sort of like a spider on a web. If it doesn't move, it's too tight. If it plummeted to the floor, it's too loose.
If you want to be a bit more scientific about it, you can pick up a Towa gauge. This little tool gives you a numerical reading of your tension. It takes the guesswork out of the process, especially if you're switching between different brands of gammill bobbins or different thread weights. I usually find that my Gammill likes a bobbin tension somewhere around 20 to 25 on the Towa gauge, but every machine has its own little personality.
Maintenance and Troubleshooting
You can have the best bobbins in the world, but if your bobbin case is full of lint, it won't matter. Every time you change a bobbin, give the case a quick puff of air or a brush out. You'd be surprised how much "fuzz" accumulates in there, especially if you're using a cotton thread.
Check under the tension spring on the outside of the bobbin case too. Sometimes a tiny piece of lint or even a sliver of thread gets stuck under there, and it'll completely throw off your tension. If you're suddenly getting loops on the top of your quilt, that's usually a sign that your bobbin tension has gone slack because of some trapped lint.
Also, don't forget that bobbin cases don't last forever. The spring can lose its "springiness" over time, or the case can get dropped and go out of round. If you've tried three different gammill bobbins and you still can't get the tension right, it might be time to just buy a brand-new bobbin case. It's a relatively cheap fix that can save you hours of frustration.
Choosing the Right Thread for Your Bobbins
The thread you put in your bobbin doesn't always have to match the thread on top, but it should be compatible. A lot of longarmers like to use a slightly thinner thread in the bobbin—like a 60-weight polyester—even if they're using a 40-weight on top. This helps the "knot" of the stitch hide inside the batting better.
If you're using those magnetic-core pre-wounds I mentioned earlier, remember to remove the backlash spring from your bobbin case. That's the little circular piece of metal that sits in the bottom of the case. The magnet does the job of the spring, and if you leave both in there, it'll create too much drag. It's a simple thing, but it's one of those "aha!" moments for people who are struggling with their stitch quality.
Final Thoughts on Your Bobbin Setup
At the end of the day, your Gammill is a precision instrument. It's built to run fast and long, but it relies on that tiny bobbin to do its job perfectly. Whether you decide to stick with the classic metal gammill bobbins and wind them yourself or move over to the world of high-tech magnetic pre-wounds, the key is consistency.
Don't be afraid to experiment a little. Buy a small pack of a few different types and see what your machine likes best. Some Gammills are surprisingly picky! Once you find the combination of bobbin and thread that makes your machine sing, buy it in bulk. There's nothing better than knowing your machine is set up perfectly, leaving you free to focus on the creative side of quilting rather than fighting with your tension every five minutes. Happy quilting!