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How to properly show compound angles of a feature using GD&T?

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Gaganaut06

Aerospace
Joined
May 2, 2023
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21
Location
IN
I have a drawing of a fitting which connects to a tube at a compound angle of 30deg and 45deg. Is this the correct way to show this (attached)
 

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The views are fine, but the angularity tolerance is ambiguous as it is not clear which feature it applies to - is it the OD or the ID of the tube?
You should attach the angularity tolerance to the relevant size (diameter) dimension, and if you would use a single angularity tolerance, in view A only with a diameter symbol, you could create a single cylindrical tolerance zone for the axis that would control the compund angle instead of having two different requirements for the same axis (each time limited by a different parallel-planes tolerance zone).
 
To establish an angle one needs references. You have only the reference to [A], so you need one more reference to control clocking relative to whatever is important. You have suitable dimensions, just no references defined for tolerance for clocking.
 
Hi, Azeemsha:

As 3DDave indicated, you can't have a dangling BASIC dimension (30 degrees in this case). BASIC dimensions must be traced back to its datum feature(s). You can only use a dangling dimension if it is a size dimension for feature of size.

Happy New Year!

Alex
 
Thank you, jassco, 3DDave, Burunduk, for your clarifications. I have attached the updated drawing. Hope this is correct.


Happy New Year
 

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Hi, Azeemsha:

The print looks Ok as long as you know that this feature with dimension dia. 17 is not located. You will also need a size tolerance for this dimension.

Best regards,

Alex
 
Hi, Azeemsha:

The print looks Ok as long as you know that this feature with dimension dia. 17 is not located. You will also need a size tolerance for this dimension.

Best regards,

Alex
Is it wrong to assume that OP is expecting standard-size tubing whose diameter won't really be controlled by the manufacturer of this part?
 
Hi, Flying Whale:

Those 30 and 45 degrees BSC angles only control orientation. They do not locate the feature.

Best regards,

Alex
 
Hi, Flying Whale:

Those 30 and 45 degrees BSC angles only control orientation. They do not locate the feature.

Best regards,

Alex
I see now that you were talking about the location of the part, I misunderstood it as if you were saying the 17mm diameter dimension needed tolerance.
 
It is not location of the part. I meant relocation of the cylindric feature in the part.

Best regards,

Alex
 
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