Pickett 6-T Statistical Quality Control Rule

The N-6T Statistical Quality Control Rule was produced in the United States from the early 1950's to possibly until 1976 when Pickett stop the slide rule production. Fabricated initially with magnesium in the 1950's, the rules were fabricated with aluminum in the 1960's. The scales were photo painted on the coated metal, rather than being engine divided. The rule is hold with metallic braces and has a plastic cursor with aluminum runners.

One of the main purposes of this rule was to help in the development of Quality Production Charts, an statistical tool to supervise if the quality of products or services "is in control", this is, if the quality of this product is between specified maximum variations from the desired quality. A more detailed description of this process embedded in an interesting historical background can be found in Reference (1).

The scales on the N-6T rule are: A2, D3, D4, DF [CF, d2, A0, D0, CI, C] D, LL3, LL2, LL1 on the front face, and LL0, LL00, P0, A [B, F, F, S, T, C ] D, B0, f, L on the back face

The next document shows some statistical problems solved using of the N 6-T

(IN PREPARATION)

Click on the next links to see professional panoramic pictures of the 6-T model

Model 6-T (Magnesium)

https://www.sliderulemuseum.com/Pickett/Pickett_Model_6-T_Statistical_OrionMillerCollection.jpg

Model 6-T (Aluminum)

https://www.sliderulemuseum.com/Pickett/Pickett_6-T_Statistical_GiftOfLeroyHauslerCollection.jpg

References:

• (1). Craven, Bruce: Thoughts on Japan, Deming, Quality, and the Statistical Quality Control Slide Rule. Journal of the Oughtred Society. Vol 9, No 2 Fall 2000 https://osgalleries.org/journal/pdf_files/9.2/V9.2P59.pdf