Chapter 10
How the two threads work together
The needle carries the upper thread through the fabric while the bobbin supplies thread underneath. Correct tension allows the two threads to lock within the fabric, producing balanced stitches and a clean appearance.
Know your bobbin
Bobbin Thread
Use the bobbin type and thread specified for the embroidery machine. Consistent winding and smooth feeding help maintain stitch quality.
Bobbin Case
The bobbin case controls lower-thread resistance. Check for lint, damage, correct insertion and smooth thread delivery.
A useful tension check: satin-column test
Stitch a satin column, then inspect the underside. Madeira describes an approximately one-third / one-third / one-third balance: bobbin thread in the center and upper thread visible along each side. This is a diagnostic guide, not a universal rule for every stitch.
Quick Fact
Tension is the resistance applied to thread as it moves through the machine.
Dynamic Perspective
Before adjusting anything, check the bobbin, thread path and test-stitch appearance.
Magnetic embroidery bobbins
Why use a magnetic bobbin?
Magnetic bobbins help resist over-spin (backlash) as the bobbin gets lighter. This can provide steadier lower-thread delivery, fewer loose loops and less need for tension readjustment. Both types are prewound with polyester filament thread.
Magnetic Core
Sideless construction. Magnet in the center core; no side discs. Madeira Style L example: 308-507, white, 148 yards per bobbin.
Magnetic-Sided
Magnetic disc and paper side. Magnet on one side disc; paper on the other side. Sided bobbin. Madeira Style L example: 308-509, white, 134 yards per bobbin.
Which one should you choose?
Magnetic core: a useful option when maximizing thread per bobbin and reducing bobbin changes are priorities.
Magnetic-sided: combines magnetic rotation control with a paper side that holds the winding in place. Neither is automatically better for every machine; test for smooth running and consistent sew-outs.
Important: bobbin case setup
Madeira directs users to remove anti-backlash springs when using its magnetic bobbins. First confirm the correct bobbin style (L or M), case design and machine-manufacturer instructions. Insert magnetic-sided bobbins with the magnetic side facing into the metal case.
Quick Fact
Style L and Style M are different sizes; do not substitute one for the other.
Dynamic Perspective
Try both compatible types on a sample run; compare tension, stitch quality and downtime.
Reading the underside of a satin stitch
What the underside tells you
Too Loose at Top
Little bobbin thread is visible in the center.
Balanced
About one-third bobbin thread in the center.
Too Tight at Top
Bobbin thread occupies too much of the underside.
Use the test to guide adjustments
Madeira advises checking bobbin-case tension first with an appropriate gauge, then fine-tuning the upper-thread tension. Follow the machine and bobbin-case manufacturer instructions. Change settings in small increments and stitch another test after each adjustment.
Keep a reference sew-out
Save a sample that stitches well on the same garment, backing, needle and thread combination. It gives operators a consistent visual standard for future orders.
Quick Fact
The one-third guideline applies to the underside of a satin test, not every stitch type.
Dynamic Perspective
Make one controlled adjustment at a time and retest before production.
Troubleshooting stitch quality
Check the simple causes first
Bobbin Thread on Top
Check bobbin insertion, thread feed and tension balance.
Loops or Loose Stitches
Rethread the machine; inspect thread path, bobbin and tension.
Frequent Thread Breaks
Check needle condition, size, thread path, burrs and excessive tension.
Puckering or Gathering
Check hooping, backing, stitch density and thread tension.
Irregular Stitches
Inspect bobbin winding, lint, needle and machine setup.
Inconsistent Repeat Jobs
Verify the same materials, settings, bobbins and approved sew-out.
A practical pre-production sequence
1. Confirm Bobbin and Needle
Confirm the correct bobbin and needle.
2. Rethread and Clean
Rethread and clean the thread path.
3. Check Bobbin Tension
Check bobbin tension using the recommended method.
4. Sew a Satin Test
Sew a satin test.
5. Fine-Tune Upper Tension
Fine-tune upper tension only if needed.
6. Approve a Sample
Approve a sample on the actual fabric.
Quick Fact
A thread break does not automatically mean the tension is wrong.
Dynamic Perspective
Use Madeira guidance and the machine manual together; record settings that produce a good result.
Previous chapter: Stitch Types, Density and Underlay
Next chapter: Embroidering Different Fabrics and Garments β