Dial Test Indicator Flaw

Z

Zirok

#1
Hi
I am doing a project using dial test indicator.
As seen in Image 1, I have clamped the part in such a position that it is 45 degrees to X & Y axis.
Now as shown in Image 2, I go 20 mm offset from the zero point (Zero Point is shown in blue color) & move in Y axis until reading is shown on dial.
On similar grounds, I go to 20 mm offset from zero point in opposite direction (see image 3 ) & move in Y axis until reading is shown.
The machine movement in Y axis from Zero Point should be same in both the conditions as mentioned above. But there is variation of 0.453 mm in both the positions (Refer Image 4).:(
In short, the dial test indicator needs feeds of different values to create the same reading on dial. :rolleyes:
We have ensured that the dial clamped is perfectly parallel to Y axis, so there is no issue of contact Point Error.:D
I think this problem has never been noticed by anybody in history till date:mg:
How can this happen & what should be the error & how to compensate that error.??
It is definitely not a Co-Sine Error (Refer Image 5). It is clearly visible that the angle of lever arm is almost 90 degree to the part.:D
To know more, I had a broken Dial Test Indicator & then disassembled all the stuff to know actually how the dial mechanism works. ( Refer Image Internal Assembly )
As you can see In Image 6, how the mechanism works. It doesn’t seem to be a unbalanced dial. It is a simple mechanism & logically there should be no error.
Need help
 

Attachments

Elsmar Forum Sponsor

bobdoering

Stop X-bar/R Madness!!
Trusted Information Resource
#3
I don't have the time right now to sort out the issue, but a couple things come to mind to rule out:

1. Are you sure the angles of the piece being measured are precisely correct?
2. How are you measuring the machine movement? Is it accurate?
3. Is it .453 mm? 453 microns? How can you measure that with a test indicator?
 
Z

Zirok

#4
1. Are you sure the angles of the piece being measured are precisely correct?
Its a Slip Gauge which is undoubtely a perfect square

2. How are you measuring the machine movement? Is it accurate?
Its a CNC Mill. So the accuracy cannot go beyond 25 micron at the most.

3. Is it .453 mm? 453 microns? How can you measure that with a test indicator?
I Zeroed Y axis on Machine screen when the dialed on the left hand side & then moved to right hand side & after dialing, saw the difference in Y axis on Machine Screen.

Thanks,
Zirok
 

Stijloor

Staff member
Super Moderator
#5
That type of indicator is only accurate when the plane in which the needle swings is at 90 degrees to the measured surface instead of 45 degrees.

The measuring force, even though very small, will push the needle sideways (left and right) resulting in different readings.

You're asking the indicator to perform a measurement for which it was not designed.

Stijloor.
 
Z

Zirok

#6
See, the part moves the needle to provoke readings. In short the part fights against the weight of the needle to move it.

So why not increase the weight on 1 side (where it is showing deviation) .;)

& in short balance the side thrust so as correct results are achieved.
 

Stijloor

Staff member
Super Moderator
#7
See, the part moves the needle to provoke readings. In short the part fights against the weight of the needle to move it.

So why not increase the weight on 1 side (where it is showing deviation) .;)

& in short balance the side thrust so as correct results are achieved.
OK. Why do you want to do this? What is it you're trying to figure out?
The application is wrong, so why pursuing it? :confused:

Stijloor.
 
Z

Zirok

#8
Ya, i know that i am driving crazy in wrong direction.


Just to give a chance...Who knows wonders :rolleyes:
 
Thread starter Similar threads Forum Replies Date
A Dial Test Indicator Repair Procedure General Measurement Device and Calibration Topics 3
A Dial Test Indicator Design & Operation when Approach Angle is Different General Measurement Device and Calibration Topics 5
M Lever type dial gauge - Usage of a dimensional 'test indicator' for measurement General Measurement Device and Calibration Topics 10
E What is the smallest graduation (resolution) available for a Dial Test Indicator? General Measurement Device and Calibration Topics 2
R Pressure Test Dial Gage Selection Quality Tools, Improvement and Analysis 1
C Correct Calibration Method for Dial Depth Gage General Measurement Device and Calibration Topics 6
G Uncertainty Budget Examples for Caliper, Micrometer and Dial Gauge Measurement Uncertainty (MU) 3
N Digital vs Dial Caliper Comparison Measurement Uncertainty (MU) 17
C ISO 9001:2008 Audit Major Finding - Dial Calipers not set to zero ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 16
N Procedure/calculation for determining the foot pressure of dial thickness gauge General Measurement Device and Calibration Topics 11
E How to perform Discrimination check for Dial Indicator? General Measurement Device and Calibration Topics 2
N Calibration Method of Dial Thermometer Gauges General Measurement Device and Calibration Topics 7
S Interpreting the Calibration Report for my Dial Indicator General Measurement Device and Calibration Topics 3
D Calibration of a Dial Indicator only used to indicate 0 General Measurement Device and Calibration Topics 7
W Measuring the Dial Torque of Plastic Insulin Pen devices Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 4
F What are the Advantages of a Digital Caliper Compared with a Dial Caliper? General Measurement Device and Calibration Topics 8
G Dial Indicator Calibration Frequency - ASME/ANSI B89.1.10M-1987 Calibration Frequency (Interval) 4
J I'm looking for a Thin Drop Dial Indicator Inspection, Prints (Drawings), Testing, Sampling and Related Topics 1
U Dial Gages of all types in company flood - How to recover them General Measurement Device and Calibration Topics 6
M Looking for a copy or template of a In House Calibration Report for a Dial Indicator General Measurement Device and Calibration Topics 1
Q Mitutoyo USB Cables for Variables Data Collection using a Dial Snap Gage Statistical Analysis Tools, Techniques and SPC 2
A Magnification for One Stage Dial Gauge Mechanism General Measurement Device and Calibration Topics 1
C Dial Bore Gage Contact Points leaving witness/burnish marks General Measurement Device and Calibration Topics 10
J Performing Internal Calibrations - Dial gauges, micrometers, height gauges, calipers General Measurement Device and Calibration Topics 8
1 Acceptance criteria and related standard for 1 micron Lever Type dial Indicator General Measurement Device and Calibration Topics 5
L Calibration of Dial Thickness Gauge - What reference standard need I follow? General Measurement Device and Calibration Topics 5
S Digital Dial Indicator Recommendation General Measurement Device and Calibration Topics 4
N Basic MSA - A simple way to complete an MSA study on Dial Calipers Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 5
Q Dial Indicator Verification Procedure - ANSI/ASME B89.1.10M-2001 General Measurement Device and Calibration Topics 13
D Calibration vs. Verification - Can we calibrate dial indicators in-house? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 3
apestate Etalon Dial Caliper Gage Information Needed General Measurement Device and Calibration Topics 2
R Validation of A Procedure for Calibrating Dial Calipers using Traceable Gauge Blocks General Measurement Device and Calibration Topics 6
C Verification vs. Calibration of Dial Weight Dynamometer General Measurement Device and Calibration Topics 4
L Best Caliper for Shop Use? Digital vs. Dial Caliper vs. Vernier-type General Measurement Device and Calibration Topics 53
J How to Calibrate a Digimatic Dial Indicator? General Measurement Device and Calibration Topics 5
D ANSI B89.1.10, AGD and Mil A-A-2348 Dial Indicator Standards Various Other Specifications, Standards, and related Requirements 2
T How to calibrate dial indicators, gauges and scales General Measurement Device and Calibration Topics 22
J Dial Caliper or Digital Caliper - Which is the best? General Measurement Device and Calibration Topics 27
I What is Gauge Capability? Dial Thickness Gage and Digital Vernier Calipers Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 17
C Struggling to teach a co-worker how to read dial calipers, any advice? General Measurement Device and Calibration Topics 13
J Caliper repair procedure - I need a caliper repair procedure for dial calipers General Measurement Device and Calibration Topics 2
C What is the proper method for cleaning dial calipers? General Measurement Device and Calibration Topics 4
apestate Calibrating .001" resolution Dial Calipers - Calibration and safeguarding procedure General Measurement Device and Calibration Topics 6
Q Calibration Wording for a Dial Indicator WI General Measurement Device and Calibration Topics 1
B How to Calibrate a Dial Indicator General Measurement Device and Calibration Topics 13
J Dial Calipers vs. Digital Calipers - Has anyone replaced all their dial indicators? General Measurement Device and Calibration Topics 5
P Dial Gauge (gage) Calibration Software Calibration and Metrology Software and Hardware 2
D Dial Indicator (Analogue) Calibration Work Instructions General Measurement Device and Calibration Topics 3
E Test report to certify compliance with IEC 62304 IEC 62304 - Medical Device Software Life Cycle Processes 1
E Tensile test machine, tinius olsen 602 Manufacturing and Related Processes 1

Similar threads

Top Bottom