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Wrong Volume Calculation

JH_11346936
10-Marble

Wrong Volume Calculation

Hello,

 

I am using Creo Parametric 9.0.8.0 with Windows 10. I have an odd case where it appears that Creo is measuring the volume of a part wrong. The volume output from the mass properties dialog box is showing a value of about 0.306 in^3 as shown in one of the screen shots. However, this way underestimates the volume of the part. Just the main portion in the middle can be hand calculated to about 0.7 in^3. I don't know what is wrong here. I have tried regenerating the part and swapping to fully assigned properties and then back to geometry defined, but the number does not change. Any insight is appreciated.

 

Thanks,

 

ACCEPTED SOLUTION

Accepted Solutions
tbraxton
22-Sapphire I
(To:JH_11346936)

The calcs look reasonable to me with a cursory check of the geometry. Are you certain your manual estimate of volume is accurate?

 

Your model is using relative accuracy (not an issue in this context). You should not be creating/using models with relative accuracy in Creo 7+. If you are using legacy start parts you should immediately change them to absolute accuracy.

 

volume.jpg

 

 

========================================
Involute Development, LLC
Consulting Engineers
Specialists in Creo Parametric

View solution in original post

8 REPLIES 8
tbraxton
22-Sapphire I
(To:JH_11346936)

Post the model for evaluation. There are many things that could cause the results to be unexpected as you show in the screen shots. It is unlikely that Creo is in error here. It is most likely that Creo is reporting what the user has requested.

========================================
Involute Development, LLC
Consulting Engineers
Specialists in Creo Parametric

Hi,

 

Here is the part file.

 

Thanks,

 

Looks reasonable to me.  I also modeled to print with revolve with similar results - 0.336.

My simple calculation:

kdirth_0-1730749951668.png

 


There is always more to learn in Creo.
BenLoosli
23-Emerald II
(To:JH_11346936)

I get a .3385 volume in Creo 9.0.9 without the internal cuts.

tbraxton
22-Sapphire I
(To:JH_11346936)

The calcs look reasonable to me with a cursory check of the geometry. Are you certain your manual estimate of volume is accurate?

 

Your model is using relative accuracy (not an issue in this context). You should not be creating/using models with relative accuracy in Creo 7+. If you are using legacy start parts you should immediately change them to absolute accuracy.

 

volume.jpg

 

 

========================================
Involute Development, LLC
Consulting Engineers
Specialists in Creo Parametric

How do you update to absolute accuracy?

 

Thanks,

 

BenLoosli
23-Emerald II
(To:JH_11346936)

In Creo, File-Prepare-Model Properties

Third item from top of the window is Accuracy.

 

tbraxton
22-Sapphire I
(To:JH_11346936)

========================================
Involute Development, LLC
Consulting Engineers
Specialists in Creo Parametric
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