Weaving Warp Spacing: EPI low density and high density weaving
Overview:
The number of yarn ends per inch (or EPI) is the number of warp strands you must warp in one inch on the loom. It affects the design and appearance of the weaving. It can also influence the visibility of the weft yarns. Warp spacing on the loom can be at low density and high density.
Below is a comparison of low and high density warp spacing with thin and thick warp yarn and a variety of weft yarns.
Low density warp spacing
Low density warp spacing has a low EPI. Wider spacing is ideal for weaving with thicker yarn.
In the example below, the warp is spaced every half inch.
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High density warp spacing
High density warp spacing has a high EPI. With more yarn strands you can make more detailed designs.
In the example below, the warp is spaced every quarter of an inch.
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Is calculating weaving EPI important?
Calculating the EPI of a weaving project is important if you want to make sure that you have enough yarn for a weaving project.
Unlike a floor loom or a rigid heddle loom, a simple frame loom or tapestry loom does not store extra warp, therefore you only have to account for the length and width of the loom.
What to consider about weaving warp spacing?
Some things to consider before dressing the loom:
– What are the dimensions of the weaving project?
-What kind of yarn will you use for warp? weft?
-How thick is the yarn?
-Will the weaving be weft-facing or warp-facing?
-How dense or loose do you want the weaving to be?
-How much warp waste will there be?
Tips for choosing the right warp spacing for your weaving:
Sampling is the best way to test the yarn and the warp per inch, or WPI. A variety of design can be created by not only adjusting the EPI of the warp but also by mixing yarn thickness. Before staring a large project, sample a few inches of weaving with the desired yarn to see if they create your desired effect.
Density Comparison- low density versus high density weaving
Using thin to medium size weft yarn
high density
security:
thinner warp yarn yarn: The yarn is secure and it can withstand the pressure of the loom comb.
thicker warp yarn:The yarn is very secure and does not move easily once it is woven in place.
pattern appearance:
thinner warp yarn: The weft yarn appears compact and tight fitted between the warp.
thicker warp yarn: The compact appearance of the weft is emphasized even more and appear like small cells.
low density
security:
thinner warp yarn yarn: The yarn is loose and can be easily manipulated with the pressure of the loom comb or hands.
thicker warp yarn: The yarn is loose and can be easily manipulated with the pressure of the loom comb or hands.
pattern appearance:
thinner warp yarn: The weft appears as long dashes.
thicker warp yarn:The weft appears as uniformed long dashes.
Using medium to thick size yarn
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high density
security:
thinner warp yarn yarn: The yarn is very secure.
thicker warp yarn: The yarn is very secure.
pattern appearance:
thinner warp yarn: The weft yarn is contracted between the warp. It is looser than the thicker warp.
thicker warp yarn: The weft yarn appears more compact.
low density
security:
thinner warp yarn yarn: The yarn is loose and can be easily manipulated with the pressure of the loom comb or hands.
thicker warp yarn: The yarn is loose and can be easily manipulated with the pressure of the loom comb or hands.
pattern appearance:
thinner warp yarn: The weft appears to flow between the warp.
thicker warp yarn:The weft flows between the warp, but the shape is more structured.
Using thick wool
high density
security:
thinner warp yarn yarn: The yarn is very secure.The roving can be moved with hands, but secure.
thicker warp yarn: The yarn is very secure- it is not easy to move the roving.
pattern appearance:
thinner warp yarn: The roving appears constricted and is not evenly disperse between the warp.
thicker warp yarn:The roving appears constricted but it is disperse between the warp a bit more evenly.
low density
security:
thinner warp yarn yarn: The roving is loose but secure. The roving can be moved with hands, but secure.
thicker warp yarn: The roving is secured but can be moved with hands easily.
pattern appearance:
thinner warp yarn:The roving is evenly woven between the warp. it is loose.
thicker warp yarn: The roving appears more compact but evenly woven.
Conclusion:
As shown above, warp spacing effects not only the security of the weft yarn and weaving structure, but also the appearance of the woven weft yarns and the amount of yarns used to complete a project. Mixing the weft and warp yarn thickness and the spacing in a project can create dynamic imagery and develop points of interests in the weaving.
As mentioned above, sampling before starting a new project is the best way to test various yarns, texture, and designs. By sampling you can explore ideas and try developing something new in your next project!
Thank you for reading- I hope that this information has helped answer your questions about warp spacing and warp yarns.
