Question on GD&T added to print - Positional callout for the small holes

Emmyd

Involved In Discussions
#1
Hi all! We have received a print that GD&T callouts were added to and I'm not sure I agree/understand some of the callouts. In the drawing below - is the B datum just the one hole? And how would you measure the 0.2 positional tolerance back to itself? If the B datum is only the one hole, there is nothing controlling the rotation around B and if B is all the holes, how do you calculate the bonus? For these holes, in the past they are only used to move volumes of air through a cylinder and if they have positional tolerances at all on them the tolerances are large enough to not even have to measure. The way these holes are called out is that there are hard tooled pins/studs that must go through each hole. I've asked for assembly information before I hit back at the engineers.

Can anyone please help? I normally don't have problems understanding GD&T callouts, but this print has got me going crazy. I also have a problem with the positional callout for the large diameter. This would normally be a profile callout in my mind.

Thanks for any help!
1559738067953.png
 
Last edited:
Elsmar Forum Sponsor

outdoorsNW

Quite Involved in Discussions
#2
In cases of multiple holes, I have always seen the datum hole(s) called out independently of the rest of the holes. I read this as designating all 107 holes as the datum.

Additionally, while I have not worked with stacked position callouts, I also think the reference to datum B is a circular reference.

You need to go back to the designer and get the print fixed.
 

outdoorsNW

Quite Involved in Discussions
#3
So I just looked up the composite control frame rules, the 107x callout is a composite position callout where the second row is a refinement of the top row. I am not going to go into all the details because I would likely do a poor job of explaining them, but the callout is definitely a circular callout with the datum B definition referencing datum B.

I suspect the intent is the one hole by the arrow is Datum B and the other 106 are following the callout, but you need to go back to the designer to be sure.
 

Emmyd

Involved In Discussions
#4
OutdoorsNW - thanks for the feedback!

That's what I was thinking as well. I'm trying to get some clarification on the function of this part in the assembly and will definitely be having a discussion with the designer.
If you interpret the print as one hole is the B datum, then I think there needs to be a tertiary datum C at least in one other hole opposite. The part is free to rotate around the single B datum hole and would be impossible to repeatably or reliably gage the part. I also am going to question the material condition as specified in the FCF - the top line is at MMC, bottom line is at LMC. The standard doesn't really say that these conditions can be mixed like that.
 
Thread starter Similar threads Forum Replies Date
D Question regarding customer feedback process ISO 13485:2016 - Medical Device Quality Management Systems 3
A Quality engineering positions in US - question Job Openings, Consulting and Employment Opportunities 1
D Equipment Register related question ISO 13485:2016 - Medical Device Quality Management Systems 1
S Study sign off question / responsibilities ISO 13485:2016 - Medical Device Quality Management Systems 3
S Qualification question - ISO 13485 Reliability Analysis - Predictions, Testing and Standards 0
M Question for Auditors - "Off the Record" Conversation? General Auditing Discussions 14
D Question regarding ECO process, specifically for Life Science products and defining form fit and function ISO 13485:2016 - Medical Device Quality Management Systems 1
R Accelerated Aging - Creating test samples - Implantable medical device Question Other Medical Device Related Standards 4
A Question on Authorized Representative in Malaysia Other Medical Device Regulations World-Wide 3
D Limited Scope for second site Question? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 5
I ISO 2233:2000 Question - Medical Device Shipping/Transportation Validation Other ISO and International Standards and European Regulations 1
Anonymous16-2 Labeling Question (Dietary Supplements/Food) Pharmaceuticals (21 CFR Part 210, 21 CFR Part 211 and related Regulations) 1
T Question for: Cg & Cgk calculation General Measurement Device and Calibration Topics 3
N ASL Question for GitHub ISO 13485:2016 - Medical Device Quality Management Systems 6
hogheavenfarm GDT Flatness measurement question Inspection, Prints (Drawings), Testing, Sampling and Related Topics 10
A Question on ISO 14001:2015 - Are annual audits required? ISO 14001:2015 Specific Discussions 8
dinaroxentool Question about FDA Classification of a Device 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 3
J Another DFAR question 252.225-7009 AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 0
F Conflict Mineral Smelter Question RoHS, REACH, ELV, IMDS and Restricted Substances 8
R NRTL - Scope Question - Off-the-Shelf Plug In IEC 60601 - Medical Electrical Equipment Safety Standards Series 0
D API 6A Certification Question Oil and Gas Industry Standards and Regulations 4
dinaroxentool Question about qualification as a medical device or accessory in Europe EU Medical Device Regulations 2
R DHR question: Traceability of components ISO 13485:2016 - Medical Device Quality Management Systems 2
C MDR - Question around software accesories EU Medical Device Regulations 2
K My question is, what/when is a nonconformity? Therefore what requires an NCR? Nonconformance and Corrective Action 9
Watchcat Authoritative References about the Research Question? Quality Tools, Improvement and Analysis 0
T Question about Quality Department employee position titles Quality Manager and Management Related Issues 10
N Question on creepage/clearance requirements for HF Active Accessories for 2nd edition 60601-1 IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
I Question 1 - Nitpicking on Document Approval - can a document approval record be separate? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 6
J Question: How to create an IMDS RoHS, REACH, ELV, IMDS and Restricted Substances 3
K Question on whether IEC 60601-2-62 standard is applied IEC 60601 - Medical Electrical Equipment Safety Standards Series 4
B QMS question in regards to multiple medical devices/products and N/A activities Other Medical Device Related Standards 12
C NB approval - Basic question about Notified Bodies and their role EU Medical Device Regulations 10
G Question about Non-conformances during New Product Introduction Nonconformance and Corrective Action 14
F ISO 13485 8.2.3 Reporting to regulatory authorities: Question regarding a procedure for this clause. ISO 13485:2016 - Medical Device Quality Management Systems 4
O Mitutoyo Digital Caliper to PC USB question General Measurement Device and Calibration Topics 2
R Probability - Need a help to solve the below question Statistical Analysis Tools, Techniques and SPC 5
B Minitab Type 1 Gage Study on True Position Question Measurement Uncertainty (MU) 1
Q Supplier audit question cataloque VDA Standards - Germany's Automotive Standards 0
Ed Panek Inactive key supplier question - We are not actively buying from them ISO 13485:2016 - Medical Device Quality Management Systems 2
T Potential Off-Label Use question 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 5
R Question on determining defective units - I am not recording fixture to part rejected Statistical Analysis Tools, Techniques and SPC 5
Ed Panek Rule 11 Question - CE approvals for software as well as the medical device EU Medical Device Regulations 6
H Question about implications of performing Firmware upgrade via MDDS - Medical Device Data Systems 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 2
D Company Moving - Relabelling Question Medical Device and FDA Regulations and Standards News 0
Ronen E Tolerance intervals (?) question - Flow Rate Probability Range Statistical Analysis Tools, Techniques and SPC 6
S Conformity Assessment Route question for Class IIa medical device under MDR EU Medical Device Regulations 3
K AS9100D 8.4.1.1 external providers question - Walmart, Home Depot, our lawn care team. etc. AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 20
J IEC 60601-1, ed 3.1 - Blue icon question IEC 60601 - Medical Electrical Equipment Safety Standards Series 4
A PFMEA English language question IATF 16949 - Automotive Quality Systems Standard 4

Similar threads

Top Bottom