Sock Testing Consortium
Sizing and Fit Committee
A Better Idea About Sock Sizing
Mission Statement
To Review and Investigate Ways to Improve the Current Methods for Determining Proper Fit in Knee High and Shorter Hosiery.
- Consistency of Reading
- Does Fit Match Size?
- Repeatability of Measurement
- Practicality. Must be useable in “Mill Environment”
Steps in the Process
- Performed a literature search
- Created a timeline.
- Surveyed retailers on their needs.
- Designed tests and performed 1st through 4th round of tests.
- All results were analyzed using statistical methods. We looked at both within machine variation and between machine variation.
- Determined calibration procedures of the machines.
- Created test methodology with 4 machines that passed along with creating an extensive web site with all information posted.
- Had successful rollout in September 2000 with over 180 in attendance.
Major Causes of Variability
- Operator influence- loading, interpretation of readouts
- Resolution of Scale on readouts(1/4” vs. 1/8”)
- Sock Construction
- Machine Calibration
- Machine Variation
Variation Within Testers Greatly Improved
- HIFO - 30 % Reduction in Variation
- DSC - 41 % Reduction in Variation
- CIMation Scissors – 35 % Reduction in Variation (Compared to old scissors)
Current Approved Devices
- Dinema DSC (Both New and Old models)
- HIFOMACO LCS 4800
- HIFOMACO HT-36L
- HIFOMACO Scissors
- The HIFOMACO HT-36T, LCS 4800, Scissors and Dinema DSC
Models all now show consistent non significant variation
within and between testers
- Your resource for testing socks now and in the future.
- Detailed descriptions of all approved methods, equipment, calibration procedures and recommended measurement points.
- Constantly updated with dates of the last changes.
- Printout from web to booklet.
Conclusions
- Finished socks should be tested for FIT on appropriate NAHM forms both before and after 3 launderings (following AATCC test method 135) -- excluding the use of the Durometer due to its unacceptable and excessive variation within test sample groups.
- Once FIT has been determined using the appropriate NAHM sizing form(s), a "statistically sound" stretch machine should be used to document standard "stretch" dimensions at specified measurement points.
We are done Right? -- Not Quite!
Now that we have machines and sizing methods that are
repeatable, what should they read? We still do not know what
amount of cross or length stretch would fit comfortably.
- Much consumer confusion about what is a size 10-13 etc.
- Shoe sizes are all over the board.
- How do you figure in the fit characteristics of some of the new stretch yarns? (Tony will elaborate later)
- Can we predict what is the variability we should expect
in a knit fabric?