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min dimension in view
hello,
question about min dimension in view.
on the drawing there are two concentric diameters shown in a cross section view. there is a min dimension between the two diameters. the min does not state all around.
how would i know if the min is specified at that particular location or if it is interpreted to be anywhere between the two diameters?
robert
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let me get this straight. is the min shown on a section cut through the diameters and you're not sure if it applies all around or just where the cut is taken?
one of the diameters has a diametral callout (right?) and the min dimension is controlling the wall thickness between the two features. this is often done on tubes to control the wall, but is toleranced, and the all around is obvious, but i would ask, what is the max? is another dimension controlling that?
thank you for your reply.
i would have thought it straight forward as well. the diameters have diameter symbols.
the view is not a wall thickness. it is two stepped internal diameters (similar to a counterbored hole). the min is shown in a section between the two steps. i was using the min to control the location of the holes in lieu of using a positional geometric.
i am told that the min applies just where i placed it and it is not checked all around. i was hoping to find something in one of the asme specs which states when dimensions are all around vs just in the view.
thank you for your input.
robert
what you are told about the min being just where you placed the dimension is not correct. i don't know where in a standard this is stated but i do know that if it were a square that were being dimensioned, and the leader line extended off of one end of the square, you would not have to state that the dimension had to be held on the other end of the square as well. check fundamental rule 1.4(m) and see if you can use it.
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i agree with powerhound. as a kluge to get around this, you could add "(all around)" to the dimension, but if someone insists that your original dimension applies to only one location, they will probably ask the question "all around what?"
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i also agree with powerhound that on a circular feature all around should be obvious without need to state it.
pararaph 1.4(m) seems to apply to your situation.
question: why not use a positional tolerance fcf on the features? seems like a better (and normal) way to specify the features.
thank you for your help with this. i used the fundamental rule 1.4(m) to clarify the requirement. in the future i will be using a positional geometric fcf as i believe this will allow no misinterpretation.
thanks for all the input.
robert