What Is Bobbin Backlash?
Bobbin backlash occurs when the longarm machine accelerates or decelerates quickly and the spinning bobbin's inertia causes it to keep rotating after the machine has stopped or slowed -- releasing excess thread that accumulates as loops, bird nests, or thread tangles on the back of the quilt. It is particularly common at the start and end of quilting rows, when the machine changes direction, and during computerized quilting where acceleration and deceleration happen frequently. The Anti-Backlash Spring is a simple mechanical solution: a small spring component installed in the Towa bobbin case that applies light braking resistance to the bobbin, preventing it from free-spinning during machine deceleration.
The Non-Solid Circle Spring Design
This specific spring is the non-solid (open circle) design for Towa M-size bobbin cases -- the appropriate spring for Gammill machines using Towa cases. The open circle design allows the spring to apply consistent, controllable resistance to the bobbin without over-tensioning it. The spring is a small metal component that installs inside the bobbin case in a specific position -- check Gammill and Towa documentation for installation instructions specific to your case model.
Top 10 Benefits
- Eliminates Bobbin Thread Backlash Loops -- The direct fix for thread loops and bird nests caused by bobbin inertia at deceleration.
- Cleaner Quilt Backs -- Fewer loops and thread tangles on the back of production quilts.
- Fewer Machine Stops for Thread Knots -- Backlash-related bird nests are a leading cause of production stops; the spring prevents them.
- More Consistent Tension During Direction Changes -- Particularly valuable for computerized quilting where frequent direction changes create repeated deceleration events.
- Lower Risk of Thread Breaks -- A backlash loop that catches during the next stitch formation can cause an abrupt thread break; preventing the loop prevents the break.
- Extended Bobbin Case Life -- Reducing the mechanical stress from backlash events reduces wear on the case and bobbin interaction surfaces.
- Better Performance at High Speed -- At production speeds, acceleration and deceleration are more abrupt; the spring's benefit increases with machine speed.
- Essential Spare Part -- Springs are small and can be lost or damaged during bobbin case cleaning; having extras on hand prevents interruption.
- Low-Cost, High-Impact Fix -- One of the least expensive improvements to longarm production consistency available.
- Compatible With Multiple Bobbin Cases -- A pack of springs allows you to equip all your Towa M-size cases simultaneously.
Installation
The anti-backlash spring installs inside the bobbin case body in a specific position relative to the bobbin. Consult your Towa bobbin case documentation or Gammill's maintenance guides for precise installation instructions. Proper installation is important -- an incorrectly installed spring can affect tension or create additional mechanical issues.
Frequently Asked Questions
Will the anti-backlash spring affect my bobbin tension?
A correctly installed spring applies very light resistance that may marginally affect bobbin tension. Test stitching after installation and adjust the tension screw if needed to maintain your target tension setting. Use your Towa TM-3 gauge to verify the tension after spring installation.
How often do anti-backlash springs need replacement?
Springs are durable under normal use but can fatigue over time or be lost during bobbin case cleaning. Having 3 to 5 spares on hand is a sensible practice for any production studio.
Is this spring compatible with bobbin cases other than Towa?
This specific spring is designed for Towa M-size bobbin cases. Verify compatibility with other case brands before purchasing.
Shop Anti-Backlash Spring for Towa Bobbin Cases
The small spring that fixes one of production quilting's most annoying problems. Keep a supply on hand.
