10 Steps to Warping – Step – Calculate Warp Yarn
Even if you have a pre-determined pattern, it is a good idea to double check that you have sufficient yarn to complete your project.
Take-up and Shrinkage
To calculate the length of warp required, take the length of your finished project and add 10% – 15% for take-up and shrinkage.
- Finished project: Table Runner length = 36″ + 2 inch hems = 40″
- Take up and shrinkage 15% = 6″
- Total length = 46″
You will need additional warp length to be able to tie the warp ends to the back and front of the loom. This is called loom waste. Loom waste is generally about 27″ but I add a full yard for loom waste. This gives me a few additional inches of warp for sampling and playing with new designs or colours.
So, for this project you would need:
46″ + loom waste 36″ = Total 82″ or 2.3 yards warp length.
Because there is always a considerable amount of loom waste in a weaving project, it is usually advisable to make more than 1 item at a time.
To make 2 table runners, the warp length would be:
2 x 46″ = 92″ + loom waste 36″ = 128″ or 3.5 yards.
Width of Project
Next, you will need to know the desired width of your project. Add 10% – 15% for take-up and shrinkage.
- Project width: 17″
- Takeup and shrinkage – 15%: 2.5″
- Total width: 19.5″
EPI – Ends Per Inch
You will now need to calculate how many ends of yarn you require. Using the sett that you figured out above, multiply the sett (number of ends per inch) times the total width of the project.
- Sett: 20 epi
- Total width: 19.5″
- 18 x 19.5″ = 390 ends
Each warp end will be 3.5 yards long and you will need 390 ends. To calculate the total warp length, multiply the total warp length x the total number of ends.
- warp length: 3.5 yards
- # ends: 390
- 3.5 x 390 = 1365 yards
YPP – Yards Per Pound
Yarn is usually sold by weight, in number of lbs. or grams. The yardage measurement is sometimes shown on the cone of yarn, or you can ask your yarn supplier how many yards per pound there are in the yarn you purchased. The hemp yarn shown above has 1500 yards per pound (ypp). So you would need 1365/1500 = .9 lb. of yarn for the warp.
Don’t forget that you will need yarn to weave the weft as well. If you are using the same yarn for weft as well, you will need approx. the same amount to complete the two table runners – 1.8 lbs.
10 Steps to Warping
Step 1: FTB Warping. Front to Back Warp Method. Choose your project and yarns.
Step 2: Sett. Determine the sett of your cloth, or how many threads per inch the fabric will be.
Step 3: Reed. Choose the reed that best fits your project pattern.
Step 4: Yarn Calculations. Calculate how much yarn you will need.
Step 5: Wind the Warp. Wind the warp onto warping board.
Step 6: Warp Chain. Make a warp chain to remove the warp from the warping board.
Step 7: Sley the Reed. Sley the reed through the heddles.
Step 8: Thread the Heddles. Thread the heddles according to drafting plan.
Step 9: Beam the Warp. Wind the warp onto the back beam.
Step 10: Tie Warp. Tie the warp onto the loom.
Congratulations! Now you a ready to Weave!
AMAZON – Hand Weaving Books
The Key to Weaving: A Textbook of Hand Weaving for the Beginning Weaver
Learning to Weave
The Big Book of Weaving: Handweaving in the Swedish Tradition: Techniques, Patterns, Designs and Materials
The Handweaver’s Pattern Directory
Last Updated on April 30, 2021 by Paivi Suomi