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Calculate warp yarn requirements for loom weaving projects. Estimate total warp threads, yardage, and sett from project width and EPI.
Calculate optimal weaving sett (EPI and PPI) from yarn wraps per inch and weave structure. Balanced, warp-faced, and weft-faced sett guide.
Calculate total yarn yardage for weaving projects including warp and weft. Estimate cones needed from project dimensions and yarn weight.
For straight threading (1-2-3-4 repeat), ends distribute equally. 400 ends on 4 shafts = 100 heddles per shaft.
Heddles per shaft = Total ends ÷ Number of shaftsComplex twills and satin drafts thread unevenly. Read the threading draft to count ends assigned to each shaft individually.
Count ends per shaft from draftVerify each shaft has enough heddles installed. Keep 5–10% spare heddles for pattern changes and repairs.
Available heddles ≥ Required + 10% spareUpdated: July 2026
Straight twill threading distributes 90 heddles per shaft. Standard 12-inch shaft with 200 heddles has ample capacity.
Satin draft may put 150 ends on shafts 1 and 5, 75 on others — count from draft, not equal division.
Single rigid heddle with 200 slots/holes handles 200 ends maximum. Double heddle setup for 3-4 shaft patterns requires two heddles.
Running short of heddles mid-threading stops your project before weaving begins. Enter total warp ends, number of shafts, and threading pattern to calculate heddles required per shaft and verify your loom capacity.