#ACCURATE 4 DIAL INDICATOR FULL#
#ACCURATE 4 DIAL INDICATOR PLUS#
#ACCURATE 4 DIAL INDICATOR PROFESSIONAL#

#ACCURATE 4 DIAL INDICATOR FULL#

Gage Durability: the indicator must survive half a million full scale deflections without showing significant signs of wear. Repeatability is checked at 1/4, 1/2 and 3/4 full range.

#ACCURATE 4 DIAL INDICATOR PLUS#

Repeatability: same as AGD, plus or minus one-fifth graduation but repeatability must remain reliable for up to 500,000 repetitions.Īccuracy: same as AGD, plus or minus one graduation at any point over the first 2-1/3 revolutions.Ĭalibration procedures: test 8 points, in equal increments, over the range of the indicator inward and outward for accuracy. MIL Specs (A-A-2348) make the following demands: Calibration labs follow these stipulations as a matter of course, wherever practical. The US Department of Defense approved of AGD specifications (that’s a good thing) but sets forth some rules for test procedures.

Refer to our ABC Index for information on specific manufacturers and gage types.

Most manufacturers' catalogs give schematics of these dimensions. Other dimensions may or may not be of importance to the gage user. Contact points will be interchangeable with 4-48 threads. In these cases, adapter sleeves will fit over the stem to increase the diameter as necessary. 375' Oftentimes, particularly on metric models, the stem diameter will measure 8 mm as an exception. More significantly, the diameter of the stem must be. Many manufacturers have arbitrarily introduced a fifth 'size 0' group for indicators smaller than Group 1. Dial indicators are classified in 4 size groups. (On metric indicators, hundredths of a millimeter.)įinally, AGD specifies manufacturing dimensions. Refer to their catalogs for details.įurther AGD specifications stipulate the range of the spindle which must be a minimum of two and one-half revolutions the hand position which must be set at 9 o'clock when at rest and the dial numbers which must always indicate thousandths of an inch regardless of magnification. Accuracy varies on gages with longer travel depending on manufacturer. Any dial indicator which is functioning correctly will also be accurate to within one graduation over its first two and one-third revolutions. Most significantly, repeatability will be within plus or minus one fifth graduation at any point.

MIL specs US Defense Department military specificationsĪll of today's dial indicators conform to AGD standards (American Gage Design) which, in 1946 established parameters for gage dimensions and accuracy.

ANSI American National Standard Institute.

#ACCURATE 4 DIAL INDICATOR PROFESSIONAL#

Professional literature on these topics is hard to find but checking Wikipedia will be a good source for starters. The intention being that we all use identical methods of measurement in order to guarantee uniform results and that one way of creating uniformity is to set certain standards that all measuring gages must have in common.

Here we list just a couple of the standards we may come in contact with, although it seems that new ones are being created annually. And, if something gets out of hand, we will be blunt with the customer and ask what kinds of compromises can be made.

Chances are we won’t know all the details of those standards, and there is no reason why we can’t ask our customer to supply us with those details. When one of our customers insists that we follow certain standards, we had better comply. (A little bit) about standards and specifications

Accurate 4 dial indicator