Zero part to part variation - Gage R&R project

#1
Hi,

I work on a gage R&R project. I and my partner used a digital caliper to measure bolt holes of two rotors (12 points) each point is measured three times. When I got the results, there is zero part to part variation! what does this mean? Also, the gage R&R %study variation is 100%.

Can I conclude that MS is not adequate?

The MS resolution is 0.01 inch
Accuracy is 0.01 inch

Thank you,
 

Attachments

Elsmar Forum Sponsor
#3
Hi optomist1,
The rotor is ACDelco Silver 18A925A Front Disc Brake Rotor. I tried to find any drawings or specification limits, but I didn't find any. It seems to me that the best bolt size is M14-2. It is the bolt size that fits the cars that use this rotor.

I found a rotor that looks like the two I have. It shows bolt hole diameter 0.635 in
 

Jim Wynne

Staff member
Admin
#4
Hi,

I work on a gage R&R project. I and my partner used a digital caliper to measure bolt holes of two rotors (12 points) each point is measured three times. When I got the results, there is zero part to part variation! what does this mean? Also, the gage R&R %study variation is 100%.

Can I conclude that MS is not adequate?

The MS resolution is 0.01 inch
Accuracy is 0.01 inch

Thank you,
What does "measure bolt holes" mean? Size? Location? Please also explain the 12 points of measurement. What does the bolt size have to do with it?
 
#5
Hi Jim Wynne,
Sorry for confusing you.
The idea is to measure two rotor bolt holes (see attached). each rotor has 6 stud holes. I did not find any drawings or specifications except for product weight 19.3 pounds, and dimensions 12.33 x 12.33 x 3 inches. See excel file for gage R&R measurements.
 

Attachments

Jim Wynne

Staff member
Admin
#6
Hi Jim Wynne,
Sorry for confusing you.
The idea is to measure two rotor bolt holes (see attached). each rotor has 6 stud holes. I did not find any drawings or specifications except for product weight 19.3 pounds, and dimensions 12.33 x 12.33 x 3 inches. See excel file for gage R&R measurements.
You didn't answer my questions.
 

Bev D

Heretical Statistician
Staff member
Super Moderator
#8
What are you atually trying to do? Do you work at the manufacturer of the rotor?
Why are you trying to estimate the hole size? That won’t help anything.
 
#9
What are you atually trying to do? Do you work at the manufacturer of the rotor?
Why are you trying to estimate the hole size? That won’t help anything.
I am a student, and I have a gage R&R project. I need to do it for any vehicle measurements using digital calipers. I chose rotors. I think estimating hole size helps to estimate the tolerance limits. I need tolerance limits in my project.

Thank you,
 

Miner

Forum Moderator
Staff member
Admin
#10
Brake rotors are precision machined on all dimensions. Digital calipers would be woefully inadequate to even begin to see the variation in the dimensions. This would be a resolution issue.
 
Thread starter Similar threads Forum Replies Date
normhowe "The Problem with Quality Management: Process orientation, controllability and zero-defect processes as modern myths" Book, Video, Blog and Web Site Reviews and Recommendations 2
P ISO 9001 certification with zero customers? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 11
D Certifying a "virtual" company with zero employees ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 11
Sam Lazzara Time Zero testing in med device aging studies Qualification and Validation (including 21 CFR Part 11) 3
C Are zero defect sampling plans relevant to AS9120B Distributor AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 4
M Zero Defect Sampling Plan Standards Inspection, Prints (Drawings), Testing, Sampling and Related Topics 4
B IATF 16949 Cl. 8.6.6 - Acceptance Criteria - Zero Defects Attribute Data Sampling IATF 16949 - Automotive Quality Systems Standard 2
WCHorn Changing Sampling Accept Number to Zero, Arbitrarily AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 15
F Zero to certification in 6 months! Covegratulations 5
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
R Can Cp and Cpk be zero? Capability, Accuracy and Stability - Processes, Machines, etc. 10
W Zero setting of correlation graph when plotting best fit linear regression Statistical Analysis Tools, Techniques and SPC 7
M Zero Tolerancing on True Position using MMC (Maximum Material Condition) Inspection, Prints (Drawings), Testing, Sampling and Related Topics 6
P Rounding Uncertainty to Zero on a Calibration Certificate Measurement Uncertainty (MU) 7
S Justifying the AQL for a Zero (C=0) Acceptance Plan (Medical Device) AQL - Acceptable Quality Level 6
L What is the Cpk for Zero Defects Six Sigma 4
optomist1 Differences and Advantages of using a Zero Positional Tolerance at MMC Inspection, Prints (Drawings), Testing, Sampling and Related Topics 3
S Getting Zero for GR&R Reproducibility? Using Minitab Software 5
V C=0 Zero Acceptance Number Sampling Plan - Question Inspection, Prints (Drawings), Testing, Sampling and Related Topics 2
R Zero Acceptance Sampling Plans 5th edition by Squeglia - Question Inspection, Prints (Drawings), Testing, Sampling and Related Topics 1
M Zero Acceptance Number Sampling Plans for Isolated Lots Inspection, Prints (Drawings), Testing, Sampling and Related Topics 6
P Minitab error: Zero or negative degrees of freedom Using Minitab Software 16
T Zero Failure Sampling Plans Inspection, Prints (Drawings), Testing, Sampling and Related Topics 2
M AQL (Acceptable Quality Level) for Zero Defects AQL - Acceptable Quality Level 13
C Can you change all your WI (Work Instruction) revisions back to zero (0) ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 11
S Is "Zero Accidents" a realistic goal? Occupational Health & Safety Management Standards 101
Chennaiite High Technology Visual Inspection for Casting and Forging Parts - Zero Defects Inspection, Prints (Drawings), Testing, Sampling and Related Topics 11
M Cpk with LSL (Lower Specification Limit) at zero? Statistical Analysis Tools, Techniques and SPC 3
Q Zero-Based Sampling Plan - Governing document or main reference document Inspection, Prints (Drawings), Testing, Sampling and Related Topics 2
P Zero Acceptance Number Sampling Plans, Fifth Edition (e-Book) Inspection, Prints (Drawings), Testing, Sampling and Related Topics 2
K Design of Lot Acceptance Sampling Plan - Zero Acceptance Number Sampling Plans Inspection, Prints (Drawings), Testing, Sampling and Related Topics 27
P Definition S-type Tolerance - Unilateral tolerance where the desired value is 0 (zero) Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 3
C AV equals Zero in Minitab - MSA with 2 Appraisers Using Minitab Software 11
U Zero findings!!!!!!!!!!! First visit back since our registration audit ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 7
I R-sq Value is Almost Zero - Linearity Study Question Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
D What does Zero Defects mean? TS 16949 Clause 7.1.2 AQL - Acceptable Quality Level 6
Y What is the confidence level for a given AQL in zero sampling plan AQL - Acceptable Quality Level 4
A Is zero defects possible? We are dealing with 25 to 30 parameters Quality Tools, Improvement and Analysis 21
D The difference between zero defect and zero defection? Statistical Analysis Tools, Techniques and SPC 4
J Zero Defect Dating Coffee Break and Water Cooler Discussions 37
G Stuck with Zero Defect target - Manufacturing Waste Target is Zero Inspection, Prints (Drawings), Testing, Sampling and Related Topics 17
Marc Ford bondholders zero in on cash, not recovery values World News 0
C Sampling plan/method that accepts on ZERO defects Inspection, Prints (Drawings), Testing, Sampling and Related Topics 0
Marc Microsoft Excel zero-day vulnerability confirmed Excel .xls Spreadsheet Templates and Tools 2
Wayne Searching for Zero - The Definitive Dimensional Metrology Reference Book, Video, Blog and Web Site Reviews and Recommendations 7
Marc Zero Acceptance Number Sampling Plan - C=0 Inspection, Prints (Drawings), Testing, Sampling and Related Topics 0
D Zero Acceptance Sampling - Is anyone is actually using this? Inspection, Prints (Drawings), Testing, Sampling and Related Topics 5
P Zero Acceptance Sampling Plan By N.L. Squeglia Inspection, Prints (Drawings), Testing, Sampling and Related Topics 4
C Can the Standard Deviation (SD) value be zero? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 13
S Gas Spectrometers - Calibration vs. Zero Adjustment General Measurement Device and Calibration Topics 4

Similar threads

Top Bottom