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Thread guide

Thread choice affects strength, sheen, stretch, and how cleanly the stitches sit in the fabric. For 95% of beginner projects, all-purpose polyester is the right answer.

The four threads worth knowing

ThreadWhat it's made ofUse forNote
All-purpose polyester100% polyesterMost projects — garments, home dec, mendingStrong, slight stretch, doesn't shrink, takes dye well
Cotton100% mercerized cottonQuilting (where the seam should "give" the same as the fabric)No stretch — can snap on stretchy fabric
Heavy-duty / topstitchingPolyester or poly-wrappedVisible topstitching on jeans, bags, upholstery; jean rivetsUse a topstitch needle (large eye)
Silk100% silkSewing on silk fabric (matches stretch and sheen), tailoring, bastingExpensive; almost invisible when pressed

Top thread and bobbin thread

Use the same thread for top and bobbin. Mixing types (e.g., polyester top + cotton bobbin) creates a tension mismatch that looks fine on the surface but unravels at the seam over time.

The one exception: when basting (long temporary stitches), some people use a fine silk thread in the bobbin so it slips out easily when removed. For all permanent sewing, match.

Thread weight (the numbers)

Thread spools carry a number like 50 wt or 30 wt. Lower = thicker. The most common weights:

  • 40 wt / 50 wt — standard all-purpose, what you'll use for almost everything
  • 30 wt — thicker, used for visible topstitching
  • 60 wt — very fine, used for piecing in quilting and for sewing delicate fabrics

If a spool just says "all-purpose," it's somewhere in the 40–50 wt range.

Color matching

  • Match the dominant color of your fabric. If your fabric is multicolored, choose the color you want the least visible.
  • When unsure, go one shade darker. A slightly darker thread blends into shadows; a slightly lighter thread reads as a contrast line.
  • For topstitching, contrast is fine and often intentional — gold thread on dark denim is a classic.

What to keep on hand

The minimum useful collection for a beginner:

  • One spool of white polyester all-purpose — won't match everything, but works for tests and basting
  • One spool of black polyester all-purpose — covers most darks
  • Whatever color matches your current project

That's it. Build up specific colors as projects demand. You don't need a wall of spools to get started.