Fabric calculator

Fabric Tightness

Calculate woven fabric tightness under plain-weave assumptions.

Max EPI

Warp tightness (%)

Max PPI

Weft tightness (%)

Fabric tightness (%)

Method and formula

\begin{aligned} \text{Max EPI} &= \frac{\text{Warp Threads in Repeat}}{(\text{Warp Threads in Repeat} - \text{Warp Intersections in Repeat}) \times \pi \times \left(\frac{\text{Warp Yarn Diameter (cm)}}{4}\right) + (2 \times \text{Warp Intersections in Repeat} \times \text{Warp Yarn Diameter (cm)})} \\[1em] \text{Max PPI} &= \frac{\text{Weft Threads in Repeat}}{(\text{Weft Threads in Repeat} - \text{Weft Intersections in Repeat}) \times \pi \times \left(\frac{\text{Weft Yarn Diameter (cm)}}{4}\right) + (2 \times \text{Weft Intersections in Repeat} \times \text{Weft Yarn Diameter (cm)})} \\[1em] \text{Warp Tightness (\%)} &= \left(\frac{\text{EPI}}{\text{Max EPI}}\right) \times 100 \\[1em] \text{Weft Tightness (\%)} &= \left(\frac{\text{PPI}}{\text{Max PPI}}\right) \times 100 \\[1em] \text{Fabric Tightness (\%)} &= \left(\frac{\text{EPI} + \text{PPI}}{\text{Max EPI} + \text{Max PPI}}\right) \times 100 \end{aligned}

Variable	Expected entry
EPI	Enter a positive measured value.
Warp diameter (cm)	Enter a positive measured value.
Warp threads / repeat	Enter a positive measured value.
Warp interlacements / repeat	Enter a positive measured value.
PPI	Enter a positive measured value.
Weft diameter (cm)	Enter a positive measured value.
Weft threads / repeat	Enter a positive measured value.
Weft interlacements / repeat	Enter a positive measured value.