Stupid counterbore and interupted chamfer questions

[2JL]

1- Is there a preferred way to callout counterbored holes? I mean, should the callout arrow be on the hole (the smallest) or on the counterbore (the bigger) instead?. The 2009 ASME standard seems to lean towards the later.

http://files.engineering.com/getfil...a3525214&file=Stupid_Counterbore_question.png

2- I have a shaft output with splines and therefore the lead-in chamfer is interuppted. How do I callout such a chamfer? Should I add a multiplier to account the individual faces or just take it as the single feature it was before the splines? The continuous feature symbol would have been useful in this case but unfortunately, it applies only for features of size.

http://files.engineering.com/getfil...f4da47a&file=Interrupted_chamfer_question.png

Thanks for you time.

2JL

 

[JNieman]

I'm glad you asked, as this is something I've wondered about as well.
My own rule of thumb which is completely imagined is - I put it the more critical feature, or if equally uncritical, the inner. I'd be very happy to know if there's a "right" way, though.


I believe the chamfer is one feature and needs one instance of callout. The drawing view removes ambiguity, so I don't think there's a vulnerability in the requirement.

_________________________________________
NX8.0, Solidworks 2014, AutoCAD, Enovia V5

 

[CheckerHater]

I think ASME Y14.5-2009 is pretty clear using the word "shall" in paragraphs 3.3.12, 3.3.14, and 3.3.14

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[JNieman]

It sure is, Checkerhater. It appears my eyes glazed over those pages, before. Thanks for clearing that up.

_________________________________________
NX8.0, Solidworks 2014, AutoCAD, Enovia V5

 

[2JL]

Spot on CheckerHater! I totally missed those paragraphs! But still there is something bothering me. These paragraphs seems to be about symbols. Is the callout a part of the symbol? Or can we say that in the standard picture weight as "law" as the word do (hope what I just wrote make sense)?

JNieman, I agree with you, the drawing view should be enough to remove any ambiguity. Counting the number of chamfer faces might just do the opposite!

2JL

 

[CoryPad]

Regarding the counterbore question, yes the figures in ASME Y14.5 can be used as the "law", so point to the outside circle.

Regarding the splined end chamfer, you do not need to use a multiplier.

 

[2JL]

Thanks CoryPad! Two silly things less to worry about for me!

 

[2JL]

Is there a way to mark a thread as "solved"? Can't find a button for that anywhere?

 

[KENAT]

I don't have the 2009 version, but urge caution over extrapolating from "the figures in ASME Y14.5 can be used as the "law" too much without the supporting text.

At least in the -1994 version there is bit of a disclaimer over figures in 1.1.4

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[CheckerHater]

These paragraphs seems to be about symbols. Is the callout a part of the symbol?

I think the phrase "The symbol shall precede... the dimension" covers it, as there is nothing in call-out, but symbol and dimension.

I... urge caution over extrapolating from "the figures in ASME Y14.5 can be used as the "law" too much without the supporting text.

To me there is enough text and pictures as the enclosed picture shows.

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[JNieman]

I think the question revolved around that of the OP: Does the leader attach to the c'bore dia, or the thru dia? The images show it always tied to the largest circle, but they don't mention it at all in the text (that I saw)

_________________________________________
NX8.0, Solidworks 2014, AutoCAD, Enovia V5

 

[ewh]

As to the disclaimer, 2009 reads "The figures in this Standard are intended only as illustrations to aid the user in understanding the principles and methods of dimensioning and tolerancing described in the text."
Of course, that can be interpreted differently as well. ;-)

"Know the rules well, so you can break them effectively."
-Dalai Lama XIV

 

[2JL]

Good point Ewh! I don't know how I managed to skip that paragraph. I guess that was not my focus the first time I read the standard. Ok so the conclusion can be that there is not a prescribed way to attached the leader for cbore hole.

 

[ctopher]

1. Small hole
2. Second image

Chris, CSWA
SolidWorks '15
SolidWorks Legion

 

[powerhound]

KENAT is correct though. In court cases, the text overrides the figures every time.

John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II

 

[CheckerHater]

In court cases, the text overrides the figures every time.

What if the text says "You shall do it as figure shows"?


"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future