if surface profile tol in the title block ok? 7

[juanMElvl300]

Hi users hope you are all doing good.

I have two simple questions.

1) is it ok to have a profile surface tolerance in a drawing title block? (see the below picture)
2) if so, with it apply to all surfaces for inspection?

I'm used to seeing the old way; this profile tolerance must be new. (to me btw)

something like this was the old tol. block
X.X = ±0.25
X.XX = ±0.12
X.XXX = ±0.06
X.XXXX = SEE DIM TOLERANCE

 

[3DDave]

If the pin can only tilt 0.2 tangentially for a maximum tangential width of 7.3 however can the correct limit case in the tangential direction be 7.5? Using 7.5 leaves too much clearance, to the feature that depends on it can be farther than expected from it's correct position.

I assume you cannot use a CAD system or you would have been able to look at this yourself. No matter.

 

[Burunduk]

The feature will be limited by a 7.5 diameter MMB, because 7.5 is the virtual condition of the pin relative to datums A primary and B(M) secondary, even when a rotational degree of freedom remains unconstrained, allowing the 7.5 diameter virtual condition (for datum feature D position) or MMB (for the case C position) of the pin to float in a ring shaped space about datum D.

 

[3DDave]

I bet you think that switching doors on the Monte Hall problem has a 1/3 chance just like the first choice did because the initial odds were 1 in 3 and that didn't change.

 

[Burunduk]

Not really,

But the way I described it is the way it works, although you probably have your own ideas of what the MMB and VC are.
The fact is, that these are agreed upon terms. Needed among other things to construct functional gages.

 

[greenimi]

I bet you think that switching doors on the Monte Hall problem has a 1/3 chance just like the first choice did because the initial odds were 1 in 3 and that didn't change.

What is the "right" answer on this tangential discussion about Monte Hall's problem?
Could you, please, kindly advise?
I am trying to understand what is/ could be the issue.....

 

[3DDave]

<off topic>

The Monty Hall problem is one where the naive expectation that the odds remain the same doesn't hold up because there is a change in the information/viewpoint of the person making the decision.

A contestant is given a selection of 3 doors and asked to pick one, presumably one with a valuable item behind it. The other two each have undesirable prizes, such as live goats (1st world problems, sigh).

When the first selection is to be made there is a 1 in 3 chance. So they pick one.

Then Monty changes to a new set of rules, like selecting a new datum reference frame. The key is understanding that. No matter what prize door the person originally selected there will be at least one that has an undesirable prize, like a live goat. If the person chose one of the live goats then Monty will not reveal the big prize (car? washer-dryer set) because then the game is over and is uninteresting. Instead he will reveal the other goat.

This means that the person knows that there are two doors remaining, one with a live goat and the other with the good prize and that they have selected one of those two - do they want to switch.

Since it appears to be 50/50 at that point one might say - why switch? The problem is that in the first round their chance of getting it wrong is 2 of 3. So 2 of 3 times they have a goat. In only 1 of 3 cases at the second choice changing their minds moves them from the prize to a goat and 2 of 3 cases changing their mind moves them from a goat to a prize.

The stumbling block is when the calculation of the odds does not include that Monty will always reject a goat - his choice of which door to reveal is never random.

A more extreme example is 100 doors - chose one. Then Monty Hall reveals that 98 of the doors had goats. The original odds were 99 of 100 that the original guess was a goat. Now it's one door has a goat, one has a prize. So 99/100 of the time the person selected a goat on the first guess and switching is the right choice and 1/100 they got the prize on the first guess and switching is the wrong one.

</off topic>

In the same way - by no longer referring to C, that piece of information that told the tangential movement allowance due to the position tolerance has been removed. The odds that the pin can have a location variation have been reduced to zero because the pin is now the origin of the measurement of where the pin is. The only impediment is the orientation in the tangential direction which does not affect where the center of the pin is relative to the center of the pin - only how fat it appears to be. If position was the only restriction then the position tolerance is also the limit on the orientation and that would give one answer. But there is also a perpendicularity tolerance that is smaller and that then is the limit on orientation.

Fixed Monte to Monty.

However - born Monte Halparin. He moved to Toronto in 1946 and found a job with radio station CHUM, where management shortened his name to Hall and misspelled his first name as "Monty" on billboards. per Wikipedia.

 

[Belanger]

Not to be pedantic (but in case anyone wants to do a web search for further info)... the game show host spelled his name Monty.

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

 

[3DDave]

Fixed it - but Google Search will make the correct suggestion anyway. See the end of the corrected post for the amazing reveal.