Metal or plastic bobbins?

Stability — plastic can flex under winding tension, subtly changing wind density and downstream tension; metal doesn't. Quality plastic works, but studios chasing tension consistency default to metal.

Self-wound metal or Magna-Glide pre-wounds?

Color economics — pre-wound jars win on the core neutrals used daily; self-winding on metal wins for the hundreds of colors that don't justify a jar. Most studios run both systems.

How many should be on hand?

12–20 wound — enough to run a queen without stopping to wind, with the day's colors pre-loaded before the first quilt goes on the frame.

Why the 80–90% fill rule?

Overfilled bobbins bind against the case and drag; the last 10% of capacity costs more in tension trouble than it saves in changes.

The burr inspection habit?

One nicked bobbin edge can shred thread for weeks before being identified — a periodic finger-test of edges catches it early and costs nothing.

M Size Metal Bobbin

1 product

Showing 1 - 1 of 1 product

M Size Metal Bobbin is the studio-standard longarm bobbin in dimensionally stable metal — the self-winding counterpart to pre-wound jars, for machines that take the M format.

Product Details

Format: M size — the standard for most major longarms (Gammill, APQS, Handi Quilter, Janome); not domestic-compatible
Material: Metal — no flex, warp, or deformation under winding tension
Thread: All standard longarm weights — 40wt Glide/Omni, 50wt So Fine!
Winding: Moderate consistent speed to ~80–90% full for best tension behavior
Maintenance: Inspect for burrs and nicks; discard damaged bobbins — a rough edge shreds thread

Frequently Asked Questions

Metal or plastic bobbins?: Stability — plastic can flex under winding tension, subtly changing wind density and downstream tension; metal doesn't. Quality plastic works, but studios chasing tension consistency default to metal.
Self-wound metal or Magna-Glide pre-wounds?: Color economics — pre-wound jars win on the core neutrals used daily; self-winding on metal wins for the hundreds of colors that don't justify a jar. Most studios run both systems.
How many should be on hand?: 12–20 wound — enough to run a queen without stopping to wind, with the day's colors pre-loaded before the first quilt goes on the frame.
Why the 80–90% fill rule?: Overfilled bobbins bind against the case and drag; the last 10% of capacity costs more in tension trouble than it saves in changes.
The burr inspection habit?: One nicked bobbin edge can shred thread for weeks before being identified — a periodic finger-test of edges catches it early and costs nothing.

Showing 1 - 1 of 1 product

Save 18%

This high quality bobbin will fit all M size bobbin cases. (The bobbin measures exactly 1 inch across) For use on Gammill long arm Quilting Machines and many other longarm quilting machines. This heavy duty metal double capacity bobbin holds twice as much thread as standard sized bobbins.

M Size Metal Bobbin

$3.29 $3.99