Skip to main content

Minor diameter of spline as the spline datum


Is it possible to use the minor diameter of a spline as  a  datum when the print requires to check the GD&T’s of other features to a spline datum?

In this days, it is known that the Spline Gauges are the best inspection tools to check the splines. Spline gauges have an advantage over old methods of checking spline dimensions because the use of spline gauges not only ensure the quickest process for acceptance, which means also less timing cost, but also eliminates the need to inspect the profiles with old ways such as three pins method, pin+dial indicator methods,etc.

 By using ‘GO’ and ‘NO GO’ spline gauges and plain ‘GO’ and ‘NO GO’  we ensure:

1    1)  ‘GO’ spline plug gauge checks the profile flank , the equally spiced angles  for all teeth, the extension of the root radius to the pitch circle diameter, pitch circle diameter and the runout of pitch circle diameter to major diameter of spline.

     2)  ‘NO GO’ spline plug checks the major diameter and space tooth width.

3   3)    GO’ and ‘NO GO’ plain gauges check the minor diameter of spline.


So, all gauges  ensure all dimension and fitting of the spline and among other dimensions also that the position of 3 min-pitch-max diameters to each other are within their tolerances. 


As a conclusion, when the GO/NO-GO spline gauges and plain plug gauges accept the spline it is possible to use the minor diameter of spline as a datum when the print requires to check the GD&T’s of other features to a spline datum. 

Comments

Popular posts from this blog

Nephilim

N 'eh - Ph 'ih- L 'ee- M /  Nepheeleem Zacharia Sitchin (July 11, 1920 – October 9, 2010)  wrote the " Nephilim " (נְפִילִים) is derived from “nafàl" and means “fall". The term Nephilim occurs in Genesis 6:1-4, describing the point of time when three things began: men began to increase in number, came into existence the daughters of men , and the sons of God went to the daughters of men and had children by them. Is the "nephillim" really only a Hebrew word? That question is very subtle, however I think it has been more a limit of thinking for linguists rather than a serious argument. Let's begin first with the probable meaning the linguists think it is. We know that the " fall"  in every language means moving downward from a higher position involuntarily, usually by an accident, which maybe was the reason why Michael S. Heiser, PhD candidate, Department of Hebrew and Semitic Studies , University of Wisconsin...

Word creation. The "D" letter origin and the "D" pictogram rule of the word creation.

  In this article I will cover  the origin of the letter  D letter, and the pictogram concept of the word creation.  It was my first discovery of the word creation. In this blog I will give my discoveries, the rules of word creation of the European languages. Multiple theories exist as to how language first originated. Nobody is sure which one is true. Certified Translations Get Pricing Order Translation What is the Oldest Language in the World? There are over 7,000 languages in the world. Could there have been a time on the earth that we all spoke one language? If so, what is the oldest language in the world?  So what was the first language?  Discovering the first language that people spoke is difficult because so many languages died and were considered lost in history. However, ancient languages still survive until today; these languages may have been transformed a lot but their old origins may be traceable. Written languages existed but this does n...

Total positional tolerance at material condition

Total positional tolerance at material condition (Hole) Suppose the Ø 1.005 / 1.010 hole is inspected and there are six parts with different ID dimensions. Their actual sizes checked with run out methods give that their actual axis is to be .006” over and up from the true position even though they have different actual ID’s. We want to know which part is within true position tolerance at MMC. Parts to be acceptable require some calculation when is used the run out method.             In GD&T, maximum material condition (MMC) refers to a hole that contains the greatest amount of material.             To understand and memorize simply and logically the concept, I suppose that you have a part designed as a square with one hole in the center, Ø 1.005 / 1.010 . You have produced just 5 parts and measured their holes. The hole of part #1 is on the low side of its tolerance Ø 1.005" and the hole of part #5 is on high sid...