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Can profile be used without basic dimesions, but to establish orientation from datums?

Can profile be used without basic dimesions, but to establish orientation from datums?

Can profile be used without basic dimesions, but to establish orientation from datums?

(OP)
My customer wants to orientate an angled hole to two datums, yet not use basic dimensions.
Not sure if he can do that with the way he is by using position toleranceing without basics. See link.

https://dl.dropboxusercontent.com/u/45474807/New%2...

To try an meet the criteria the customer is after,
I was wondering if profile would work better to orientate the angled hole to -A- & -B- while still keeping his block tolerances.
However, I'm not sure if you can use profile without basic dimensions. I do not see why not, but I cannot find an example in any of my books.
My idea is in this link.

https://dl.dropboxusercontent.com/u/45474807/New%2...

What is anyones view on this?

RE: Can profile be used without basic dimesions, but to establish orientation from datums?

My book says profile can be used with toleranced dimensions if it is a refinement of the dimensions which locate the true profile.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Can profile be used without basic dimesions, but to establish orientation from datums?

Should note that is based on the 1994 Y14.5 standard.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Can profile be used without basic dimesions, but to establish orientation from datums?

My view for this particular case:
Regardless which control - position or profile - you choose, both linear dimension from A and the angle should be basic. Your idea is even more doubtful as the profile is applied to directly toleranced size dimension, instead of being applied to a contour described by basic diameter.

RE: Can profile be used without basic dimesions, but to establish orientation from datums?

Well, you're right that position's relationship to any datums must be basic dimensions, so the first option isn't really kosher.
Profile tolerances can be used with toleranced dimensions back to the datums (thus controlling orientation, not location), but the problem is that a profile tolerance must be applied to a "true profile." This means that the diameter of your hole would have to be changed to a single basic dimension, and then the profile tolerance would also control size.

Since it looks like you want the hole's size to be much more accurate, I would use angularity: simply take the original print but instead of the position symbol, swap in the angularity symbol and make the 16.7º a basic dimension. The closest example in the 1994 standard would be Figure 6-29.

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
http://www.gdtseminars.com

RE: Can profile be used without basic dimesions, but to establish orientation from datums?

J-P,
Angularity does not locate, so probably position will still be needed.

RE: Can profile be used without basic dimesions, but to establish orientation from datums?

Good point, pmarc -- I guess it depends on the other details. I wouldn't add position of the same value, since that would be redundant with angularity. I would make them two separate values (angularity being the smaller number).

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
http://www.gdtseminars.com

RE: Can profile be used without basic dimesions, but to establish orientation from datums?

(OP)
All very good answers. I have learned much.
I am still waiting to hear back from the customer as to what exactly he is looking for. After reading these answers it becomes obvious that his print is not just improper but also under defined. I'm guessing he is trying to control the start position with a block tolerance, while attempting to define the angle and its orientation with an illegal position control frame. Since he did not basic anything it is impossible to know.

RE: Can profile be used without basic dimesions, but to establish orientation from datums?

RONJ100,
Is it too much to ask WHY your customer wants to use datums, but opposes idea of basic dimensions?
At least your own opinion?
(You beat me to it) smile

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