True position problems

Hello. first time I post on here. im gonna try to be as clear as I can. any question please let me know.
I have this part which requires true postion . part has 9 datum ABCDEFJGH. all datum are located inside of the part
the issue that im having is that the part is relative thicker(all around) than the nominal thk=0.080 actual = 0.123
im gonna post some codes and a pic showing the error im having.
I have tried so far to update nominal for datum a(which I think is the problem) nominal=0.060 actual: 0.3218. this help a little but I don't know is this is correct
1box.txt

Attached Files

1box.txt

jaca_232 over 6 years ago

look at the dev on Z.
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Zeros over 6 years ago

Good afternoon Jaca_232,

Is this circle projected onto one of the three Datums? As far as I know a circle requires a work plane. Please provide more information so I can assist.
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jaca_232 over 6 years ago in reply to Zeros

I did the aligment . im using workplane.
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PacMan23 over 6 years ago

I work with Romer arms so I don't know if you can but, I would Use Sample hits to better locate the circle- the program says what type of sample method to use which is "sample feature" but right under that it has no Featue selected.

I wouldn't be changing any Nominals on Datums just yet

, and the very first thing I would attempt is to set up an alignment based on the FCF, so Level to Datum B...etc etc. and then measure circle using sample hits. also I would report using Legacy Dimensions and see what you get.

that deviation in Z-axis is strange and might be due to changing nominals
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jaca_232 over 6 years ago in reply to PacMan23

ok. I did another program with those sample hits. and if i did not change the nominal PLNA the deviation is bigger. because the problem is that actual part is thicker than the model.
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VinniUSMC over 6 years ago

Why don't we start from the beginning. Post a print, or a snip of the print that shows the datum structure, or a sketch of the datum structure. And post your code. And post any other information you think might be relevant (like manufacturing type, ie stamped, molded, etc).
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PacMan23 over 6 years ago in reply to PacMan23

ok so if you set up a BCA alignment and the deviation in the Z-axis is large then yes the part is definitely thicker than nominal, and those are your results. if you just want to report X, and Y then just report X and Y.

and it sounds like that's what you are wanting to do since you went as far as changing the nominals. honestly I'm not sure what your question is ?? it doesn't seem like you even asked one
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