Part Tolerance and Equipment Accuracy of thickness gage

Q

qalsang

#1
Hi
:(
We are using thickness gage to measure our part thickness. The part thickness tolerance range from +/-0.3 ~ +/-0.5. My gage resolution is +/-0.05.Is my gage suitable ?? Must the gage for measurement be always 10X more accurate than the part tolerance??
 
Elsmar Forum Sponsor

bobdoering

Stop X-bar/R Madness!!
Trusted Information Resource
#2
Re: Part Tolerance and Equipment Accuracy

A rule of thumb for gaging is that it has a discrimination of 10X of the specification in order to have some distinct measurement categories. It is not a requirement, in that attribute gaging does not fall into that requirement but are used anyway. You may want to do a Gage R&R on the measurement system - the gage, sample parts and 2 or 3 people that might be using the device. Chances are the readout may be almost 10X, but after adding in measurement error, you will have much, much less statistically significant discrimination.

On the other hand, what is the cost to get more discrimination? Does the value of the parts or the risk of the measurement justify the next leap? And if so, who would pay for it?

Interesting questions....:cool:
 
Thread starter Similar threads Forum Replies Date
C Thread Tolerance - Can I use a 3A Ring on a part that the drawing calls out for a 2A? Manufacturing and Related Processes 5
T GRR based on part tolerance or process variation. Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 7
Y How to fix weight tolerance for plastic injection molded part? Does it vary with material groups? Manufacturing and Related Processes 1
C Acceptable NDC for %GR&R part inspection to Tolerance (%Tolerance) Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
S Doubts about SPC taken in Machining - Part has +-0.01 Tolerance Statistical Analysis Tools, Techniques and SPC 5
A Setting air gauging outside of a part tolerance Capability, Accuracy and Stability - Processes, Machines, etc. 2
V Tolerance achievable for Sheet Metal Part with some weld - 0.4mm TP Manufacturing and Related Processes 5
K Profile of a Surface Tolerance - Part with a 195 mm radius on it Inspection, Prints (Drawings), Testing, Sampling and Related Topics 9
optomist1 Maximum Shift Tolerance Restrained Part - Calculation of Datum Shifts Inspection, Prints (Drawings), Testing, Sampling and Related Topics 7
C Part Tolerance and TAR (Test Accuracy Ratio) - Non-Fixed Gaging General Measurement Device and Calibration Topics 2
Miner Intro to MSA of Continuous Data - Part 9: %Tolerance for One-sided Specs Imported Legacy Blogs 3
A Best Way to Tolerance a Cylindrical Section on a Part (Customer's Design and Drawing) Inspection, Prints (Drawings), Testing, Sampling and Related Topics 4
D Part Variation, Unilateral Tolerance, Destructive Testing - Gage R&R Experts pls help Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 12
J Clarification of ISO 2768-1 - Inside bend radius tolerance - Metal stamped part Various Other Specifications, Standards, and related Requirements 2
M Tool capability / part tolerance criteria General Measurement Device and Calibration Topics 7
B Calibration Accuracy vs. Gage/Part Tolerance General Measurement Device and Calibration Topics 4
P Calculating Gage R&R with Part Tolerance instead of Total Variation Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 7
N Gage R&R - Using Tolerance method, or part to part variation? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
C Tolerance vs. Part to Part - Is it ndc? When using % of tolerance everything is fine Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 5
U How do part tolerance and gage tolerance interact? Inspection, Prints (Drawings), Testing, Sampling and Related Topics 6
L Tape Measures & Scales - Part Tolerance - Gage R&R Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 24
A Industry standard for stamped part Various Other Specifications, Standards, and related Requirements 2
P Can credentials (ID/PW) used to login be the same as when applying Electronic Signature (Part 11) US Food and Drug Administration (FDA) 2
M Mains on Patient with Part Attached to Protective Earth in Patient Area IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
M Documentation accompanying an aerospace part AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 6
H Better to retain previous made parts or one part that is perfect Reliability Analysis - Predictions, Testing and Standards 2
T Accreditations as part of 9001 - Quality checks on your company ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 5
T Customer Rejecting Part for Basic Dimension Inspection, Prints (Drawings), Testing, Sampling and Related Topics 16
H Should we stop inspecting a part if its never been rejected? Reliability Analysis - Predictions, Testing and Standards 6
M MSA - Dealing with inherent within-part variation in assemblies Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
C Multiple Part Numbers, IMDS RoHS, REACH, ELV, IMDS and Restricted Substances 2
J IEC 60601 Applied Part - Probes intended to be covered by sheaths IEC 60601 - Medical Electrical Equipment Safety Standards Series 3
M Saline Infusion- Applied Part, Patient Connection IEC 60601 - Medical Electrical Equipment Safety Standards Series 3
D 21 CFR Part 11 Assessment (Fully Compliant or Not) Qualification and Validation (including 21 CFR Part 11) 9
S Comparing measurement results for a part from two ring gage General Measurement Device and Calibration Topics 3
PQ Systems SQCpack Tech Tuesday Webinar 3-Part Series Using SQCpack Software 0
E Biocompatibility testing of our applied part seems redundant Other Medical Device Related Standards 2
A APPLIED vs ACCESSIBLE PART IEC 60601 - Medical Electrical Equipment Safety Standards Series 4
PQ Systems Device Integration with SQCpack - 3 Part Series Using SQCpack Software 0
PQ Systems Gage R&R - 3 Part Series Using GAGEpack Software 0
PQ Systems GAGEpack Tech Tuesday - 4 part series Using GAGEpack Software 0
PQ Systems GAGEpack Tech Tuesday - 3 part series Using GAGEpack Software 0
D Is an ethernet port part of the User Interface IEC 62304 - Medical Device Software Life Cycle Processes 5
C DV/PV Test Part Storage IATF 16949 - Automotive Quality Systems Standard 9
D IATF Requirements if remote plant has no interface with OEMs who are part of IATF? IATF 16949 - Automotive Quality Systems Standard 6
W Classes and Applied Part IEC60601 Electromedical Equipment IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
E How to test 8.7.4.7 d) ? What "not protectively earthed accessible part" means? IEC 60601 - Medical Electrical Equipment Safety Standards Series 3
Anonymous16-2 Sinks and Sanitation - 21 CFR Part 111 Miscellaneous Environmental Standards and EMS Related Discussions 4
O PPAP'ed part manufacturer has discontinued production Elsmar Cove Forum Suggestions, Complaints, Problems and Bug Reports 7
N Reworked Finished Goods (FG) - Part of CoPQ? Misc. Quality Assurance and Business Systems Related Topics 3

Similar threads

Top Bottom