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Incorrect Mass

dgschaefer
21-Topaz II

Incorrect Mass

WF4, M220

This is driving me crazy, I cannot figure out what is wrong.

I have a very small part that is built in inches (Proe default inch lbm Second units) but I want to report the mass in grams.  Proe, however, will not calculate the proper mass.

The setup:

I've set my relations as units sensitive.

I have a SPECIFIC_GRAVITY parameter defined with its units set as g/cm^3, and I have the relation "MP_DENSITY=SPECIFIC_GRAVITY" to set my density from the SPECIFIC_GRAVITY parameter.

I have a "WEIGHT_G" parameter defined with its units set to g.  In my post regen relations I have "weight_g = pro_mp_mass"

I have a "WEIGHT_G_man" parameter defined with no unit.  In my post regen relations I have "weight_g_man = pro_mp_mass*453.592" (default conversion factor for pounds to grams)

No geom check in the part, no alternate mass defined.

The results:

Proe shows the part volume as 0.003302 in^3.

Proe shows the part weight (lbm) as 0.000132.

Proe shows the value of WEIGHT_G as .000132 also, which is obviously incorrect.

Proe shows the value of weight_g_man as 0.060068, which is correct.

The question:

I cannot for the life of me figure out why the value of WEIGHT_G is incorrect.  I've used unit driven relations in the past and they've worked fine.  To my eyes, everything is set up correctly.

What can I do to fix this (aside from giving up and simply using the manually calculated parameter)?

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Doug Schaefer | Experienced Mechanical Design Engineer
LinkedIn
2 REPLIES 2

Isn'tthat the old hidden PTC sillyness of needing to "generate report"to get the mass props calulation to show up in other areas?

I don't think so.  I've got mass props set to calculate automatically and I'm getting values for the standard MP parameters.

I even created an MP analysis feature in the part and drove my relations off of it instead.  Same result.

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Doug Schaefer | Experienced Mechanical Design Engineer
LinkedIn
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