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Help with understanding a Profile of Surface Callout - please

Help with understanding a Profile of Surface Callout - please

Help with understanding a Profile of Surface Callout - please

(OP)
Hi all,
(Explanation of attached pdf: Top portion view of blueprint showing the datum's and area in question to those datum's, followed by images of a closer view of the questionable area plus my interpretation and finally on the 2nd page how i have been viewing it)

i have a blueprint with a profile of surface .002 to Datum A, B, and C. i believe generally when there is profile attached to datums basically it is both form and location, so in this case i would imagine two opposite lines from the angle that span plus and minus .001.

The call out is from X to Y which spans two 60 degree angles and a BASIC dimension of both .135 and .730.

Now the question:
How do i determine if the surface profile is good or not (i'm not talking about measuring). My confusion comes in the form of the .135 and .730 dimensions.
If i base this on a triangle and create the vector points to hit this surface how does the .135 come into play other than telling me what each surface point is theoretically supposed to be at? What happens if the part hits the surface and is good but the actual length shorter than the .135 BASIC yet all values are good up until i reach the end of the angled line (or even the opposite , it's longer - there is a distance of .075 +/-.005)? Does this make the profile out to location?
The other aspect, the only datum i can see this is to is DATUM A (Center line - besides being square to Datum B) but not datum C as the .730 starts off a different level.

Thank you

RE: Help with understanding a Profile of Surface Callout - please

i think the dimension 0.135 comes to play for the requirement to datum C.
for the other questions, maybe we need more info, such as what the part is use for,etc.

RE: Help with understanding a Profile of Surface Callout - please

(OP)
Thanks for the reply C43n however i'm not sure what the part is for, i'm told its a fixture and that's about it. i thought the .730 would be coming off Datum C but again it's directly tied to it because the .730 is coming off a .787 +/-.005 base that ends up being Datum C.

Again, i'm more interested in the callout of the profile of surface given that the basic dimensions are not really to the actual feature itself with the .002 profile tolerance.

For example i have this attachment (i don't remember if i found it on this website or another) that shows a similar example in terms of the profile to be within 4mm for segment A to B and off of Datum A and B.

However the blueprint example does not provide this type of information as it has the basic dimensions on the corners of the angled portion.

My thoughts would be that the intersection of the two triangles need to be 0 to Datum A and 90° to Datum B, but not sure about C as the .135 and .730 are not datums. But if i just go off the information of BASIC .135 and BASIC .730, if the angled portion is good but the length (the hypotenuse) is shorter or longer, does this mean location is off even though the angled portion, up until .135 distance, is good?

RE: Help with understanding a Profile of Surface Callout - please

i think maybe you can take it this way: the profile the projection of that feature on Datum A B and C must within .002, thus if any of the dimension of 0.135 or 0.730 goes wrong, it won't reach the requirement!!!

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