Quoted Tolerances Trumping Drawing Tolerances?

Wes Bucey

Quite Involved in Discussions
#11
I ran into this one recently. Supplier quoted industry tolerances which were not as tight as our print. They submitted PPAP saying they could not meet our print but could meet the industry tolerance they quoted. Quality (my) department rejected the PPAP for not matching print. Pi#@ing match ensued about forcing the supplier to comply :confused: or changing our print. Ended up changin our print.

It is poor design & development processes that let this stuff happen. If it was done right up front the prints would be set to match what is needed, feasible and cost effective. It should be taken care of long before PPAP.
Actually, the situation as I see it was that a combination of supplier approval and contract review combined to select a supplier without capability to perform.

Usually, in my consulting practice, I see customers and suppliers who really work hard on getting the capability issue ironed out and then omit the capacity issue - often suppliers accept quantities and delivery dates they are incapable of meeting. Both capability and capacity are important issues and should ALWAYS be considered and addressed by BOTH supplier and customer. Mistakes in estimating either happen, but most often they weren't given much weight in the decision (most often, one or both of the parties was distracted by PRICE!)
 
Elsmar Forum Sponsor

bobdoering

Stop X-bar/R Madness!!
Trusted Information Resource
#12
The argument was that because it was evidentially OK with the customer, the PPAP requirement was superseded. The auditor replied that exceptions should be explicitly documented, but in the end let it go without further ado.
Some will...others with fight you tooth and nail. I think they are abjectly wrong - again, thanks to the customer's signature - but some assessors seem to hold that in little regard.
 
T

tomvehoski

#13
Actually, the situation as I see it was that a combination of supplier approval and contract review combined to select a supplier without capability to perform.
Actually it was someone read the wrong column in a table in a specification and put the wrong tolerance on the print. Checker missed it. Supplier quoted correct tolerance, probably got a verbal or e-mail OK, and submitted actual numbers - but the print never got changed. Quality had no choice but to reject since it didn't match print. Engineering didn't want to spend time changing the print for something they didn't see as important. Purchasing didn't want to waste time finding a supplier that could build to print since it didn't matter, and nobody would quote it that way anyway.
 

QMMike

Involved In Discussions
#14
Engineering didn't want to spend time changing the print for something they didn't see as important. Purchasing didn't want to waste time finding a supplier that could build to print since it didn't matter, and nobody would quote it that way anyway.
I think you nailed it right there..... most of the time (from what I've seen) nobody wants to waste time doing it so the PSW gets signed and then I usually include a copy of an email allowing the "deviation" from the drawing.

For instance, I have several molded automotive parts in which the material does not match what is on the drawing (simple callout - 80duro EPDM vs. 60duro EPDM). I noted it in the PSW, it was signed and approved by our customer and we've been running it ever since. During our TS RR audit, it was reviewed. I ended up sending another email to our customer to see if a new drawing was ever going to get issued and their response was no - just note it on the PSW......
 
Thread starter Similar threads Forum Replies Date
Z Is PPAP Re-qualification needed in case of not quoted dimension change? APQP and PPAP 4
E Is there a need to pay for the symbol quoted in ISO 3826-2:2008? Other ISO and International Standards and European Regulations 1
J0anne Link to find 502 (f)(1) which is quoted several times in 21 CFR 820 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 8
R Tolerances for Analytical Balances General Measurement Device and Calibration Topics 3
Skooma Deburring and Tolerances - Is there a Standard for deburring or removing material? Manufacturing and Related Processes 3
B FAI and ANSI Y14.5 Trailing Zeros and Print Tolerances Manufacturing and Related Processes 3
H Thread Plug Gauge Tolerances General Measurement Device and Calibration Topics 3
W Key functional characteristic definition - Tolerances and Deviations Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 0
M Best Practice for setting tolerances on a Drawing Inspection, Prints (Drawings), Testing, Sampling and Related Topics 8
DietCokeofEvil What is the general consensus on Caliper tolerances? General Measurement Device and Calibration Topics 1
Q M-282 - Engineering Standard for Tolerances - Is it ASTM, DIN? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 4
S MSA (Measurement System Analysis) - Process Tolerances Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 9
J Tighter Tolerances than Control Plan FMEA and Control Plans 1
P Applying Combined Tolerances of Two Scales - Balance Tolerance Question General Measurement Device and Calibration Topics 9
G MSA (Measurement System Analysis) and Dimensional Tolerances Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
B Changing dimensional tolerances to approve rejected product ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 2
K Tolerances on Drawing Title Block Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
V GD&T Interpreting Datums in Two Single Segmented Position Tolerances Inspection, Prints (Drawings), Testing, Sampling and Related Topics 5
C ZZ Pin Gage Tolerances and Calibration General Measurement Device and Calibration Topics 2
W Thread Micrometer Standard Tolerances General Measurement Device and Calibration Topics 4
D ISO 8062-3 Angle Tolerances - The drawing states ISO 8062-3 DCTG 11 Other ISO and International Standards and European Regulations 1
M Thread Gage Tolerances ?Who?s The Authority?? General Measurement Device and Calibration Topics 9
N Injection Molded Nylon Part Tolerances Manufacturing and Related Processes 6
A Ppk Issue - Some Products have Unilateral Tolerances Capability, Accuracy and Stability - Processes, Machines, etc. 24
H GD&T - How to measure these Positional Tolerances on a CMM Inspection, Prints (Drawings), Testing, Sampling and Related Topics 10
S Improper Use of Tolerances & SPC Practices, or not? Misc. Quality Assurance and Business Systems Related Topics 5
M Vinyl and Cloth Cut Parts Tolerances? (Car Seats) Manufacturing and Related Processes 8
G Geometric Tolerance - Swedish Drawing which states that all tolerances are to NS 1430 Manufacturing and Related Processes 2
optomist1 ASME GD&T Certification Test - Converting Coordinate Tolerances to Profile Tolerances Inspection, Prints (Drawings), Testing, Sampling and Related Topics 8
S S-Type Tolerances: How to calculate Cs? Control Limit(s)? Statistical Analysis Tools, Techniques and SPC 8
S Typical Tools for Particular Tolerances Table? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 15
M Recording True Positioning (Geometric Tolerances) on an FAI Report Records and Data - Quality, Legal and Other Evidence 15
D Statistical Tolerances in GD&T (Geometric Dimensioning & Tolerancing)? Various Other Specifications, Standards, and related Requirements 31
D DIN 1683 Casting Tolerances - What does "GTB" mean? Other ISO and International Standards and European Regulations 7
P Gauge Design Tolerances - How to decide tolerances for gauge design? General Measurement Device and Calibration Topics 3
smryan Can Cpk be calculated without tolerances or limits? Capability, Accuracy and Stability - Processes, Machines, etc. 11
D Metric Print from Italy - Tolerances - 38.8mm -0.015/-0.045 Inspection, Prints (Drawings), Testing, Sampling and Related Topics 5
O Sum of Cpk - Updating Product Tolerances Capability, Accuracy and Stability - Processes, Machines, etc. 6
K Basis for Establishing Gage Tolerancing - "Gage Maker's Tolerances" General Measurement Device and Calibration Topics 4
E How to Determine Tolerances for Equipment Verification General Measurement Device and Calibration Topics 18
F Capability Calculation on 1 Population Multiple Tolerances Capability, Accuracy and Stability - Processes, Machines, etc. 5
L UN Class 5 Tolerances - Thread Setting Plug Gage 7/8-9 UNC 5 General Measurement Device and Calibration Topics 23
M No Tolerances given by Customer - Shirring (sewing operation) IATF 16949 - Automotive Quality Systems Standard 5
M DIN6930 What table to use - Tolerances of straight line and radii measurements Inspection, Prints (Drawings), Testing, Sampling and Related Topics 4
D Adjusting Tolerances because of available tooling? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 9
U Calculating Pp for Unilateral Tolerances Statistical Analysis Tools, Techniques and SPC 17
S Opening Up Tolerances - We have over 6000 live drawings - help please Design and Development of Products and Processes 6
T How to Calculate Process Capability for Unilateral Tolerances? Statistical Analysis Tools, Techniques and SPC 21
R Definition Basic Dimensions - What are basic dimensions? Why don't they have tolerances? Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 14
M Strict Tolerances RR/TV or RR/Tol - Automotive Requirements Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 6

Similar threads

Top Bottom