Projected Tolerance Zone 1

[steven79]

Is a projected tolerance zone "P" applied to a pin whcih sits in a hole?

It is being shown in a box for position. IS this right?

 

[ewh]

Yes (based on the info given), though it should probably be applied to the hole itself.

 

[ctopher]

Yes, I would apply it to the hole(s).

Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog

 

[dingy2]

The best application that I have seen is a blind threaded hole(s) in which perpendicularity cannot be checked. The projection is the mating part thickness and one would have to place a threaded pin in the hole with the projection value above the hole. The positional tolerances are confirmed on this pin at the hole level and again at the top of the pin.

Hope this helps.

Dave D.

http://www.qmsi.ca

 

[powerhound]

Along with a P modifier there should be a distance that the tolerance is projected above the surface. If this is not present then the control is illegal. If you are working to the 1982 standard then the projected tolerance zone would be attached below the feature control frame instead of being incorporated into it. This is one way of telling which standard you are working to if it isn't indicated or you aren't sure for some reason.

Powerhound, GDTP T-0419
Production Supervisor
Inventor 2008
Mastercam X2
Smartcam 11.1
SSG, U.S. Army
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[Xplicator]

steven79, please see ASME Y14.5M-1994, paragraph 5.5.3 and this should clarify.

powerhound, please see ASME Y14.5M-1994, paragraph 5.5.2 and FIG. 5-34 If not in FCF, does not make it illegal.

 

[ewh]

Thanks for the heads up, Xplicator, and welcome to the group!

 

[powerhound]

Xplicator,
I didn't mean the distance had to be inside the feature control frame, I meant it had to accompany the P modifier in some fashion. I guess I should have been more clear. The second part of my statement was regarding the P modifier as well not necessarily the "zone" as I stated. Sorry, I didn't mean to confuse the issue.

Powerhound, GDTP T-0419
Production Supervisor
Inventor 2008
Mastercam X2
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II

 

[ringman]

If I understand your original question, the projected tolerance would apply to the hole that the 'pin in the hole' mates with. The tolerance would require a dimension to indicate the thickness of the part that contains that hole along with the positional tolerance for the hole.

 

[Xplicator]

steven79 - Upon further review I believe the original question was to understand what the PTZ modifier means as it relates to a hole with a pin and if being in the FCF with position indicated is correctly applied. I may very well be wrong, but if this is the case then see paragraph 5.5 in the 1994 standard as well, to gain further understanding of this concept.

powerhound - sorry, just a "knee jerk" reaction from the word illegal. You were clear enough.

ewh - Thanks!

 

[ringman]

Steven 79

I have a question. Are you dimensioning a detail part or an assembly?

Thanks