Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne String Manufacture
Name: Faye
Status: Educator
Grade: K-3
Location: MT
Country: USA
Date: November 2005


Question:
My students want to know how string is made?



Replies:
The process is similar to making yarn, although usually with a tighter twist. The fiber, often cotton, is prepared for spinning by cleaning debris out of the fluff, combing it so all the fibers are aligned in parallel order, then spinning small bits at a time into a long thin string. Most string has at least 3 or 4 plies, made by spinning/twisting together 3 or 4 of the long thin strings spun previously. Some string actually has the plies braided together to make it stronger. Plied string can be again plied with other plied string to further strengthen the finished string.

If you untwist a length of string, you may well find that each of the three or four plies contains several fine, loosely spun, finer plies which have been loosely twisted together.

Materials used to make string or rope include: cotton, jute, hemp, sisal, linen, various manmade fibers such as nylon and polyester.

Rope walks were long narrow corridors where a team would twist together long heavy strings to make ropes, such as are needed to secure ships at piers. One person would hold one end of the bundle being twisted while the other person, standing far away, would twist the groups of ends together. When the twist is as tight as possible, that end of the bundle is brought to the other end, allowing the rope to twist on itself as it is doubled. Both ends are secured to hold the twist, and a strong rope has been formed. When the lengths needed for ship's ropes are involved I presume more than two people worked together as those lengths would be difficult for only two people to control. For shorter lengths this process can be done by two people.

Strength in string or rope depends on several characteristics, including the fiber used, the number of plies, the tightness of the twist, the abrasion resistance of the fiber, which can be aided to some degree by the twist, the thickness of the finished string or rope. You would not want to tie up an ocean liner with kite string, nor would the rope used on the ship work very well when you want to fly a kite. Yet both are suitably strong for their intended purpose. Another consideration in designing the strength of string/rope will be how strong the fiber is when wet, and how it is affected by exposure to sun, heat, cold.

Strength is not the only thing to consider. Flexibility and durability are also important, as are many other attributes.

Korah A. Erbacher



Click here to return to the Material Science Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory