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mass properties wrong

wadero

New member
Have an assembly of an aeroplane.
the parts are, fuselage(1.6 kg), engine(2.6 kg), tailplane(180gr) and landing gear(250gr).
If I retrieve mass properties of the whole, it says 550kg in stead of (1.6 + 2.6+ 0.18+0.25=4.63 kg)
If I retrieve masses of parts without the fuselage they are correct. If I retrieve mass of a part and the fuselage it's again incorrect (550kg). Fuselage alone is correct. So it seems to be something with the fuselage?? if it goes along with another part. Anybody knows??
What should I post to explain things?

Best regards
 
I think there is something heavy on the fuselage. Possible that there is hidden bodies
that adds weight to the whole assembly. Try to check. Have encountered this problem before which is very critical in material quotation.

Cadharts
smiley4.gif
 
The incorrect reading is 550kg indeed, no hidden bodies, I've checked that several times, as a matter of fact, the mass of the fuselage alone is correct represented in the assembly (1.6 kg) only when I include other parts sucht as tailplane or landing gear or whatever or the whole assembly, the total mass is read as an absurd 550 kg. Smells buggy to me, by the way I use SW2010premium version.
Must say this is my first SW project and I have certainly fiddled about somewhere, question is which one did the trick.
Edited by: wadero
 
In addition when I retrieve mass of the cowling in Part "fuselage", mass isn't consistent with material volume.
Normally mass is mass density times volume? well here it isn't.
Cowling is a body made of a surface loft thickened and mirrored and material is a customized fiber glass laminate of 1600kg/meter^3 mass density.
 
wadero,


Something defintely sounds fishy... Have all these parts been created in SW, or have some been imported? Also, do you have a mix of solid/surfaces? Are there any parts with "assigned mass properties"?


Last question - Would it be possible for you to share the files?


Jim
http://www.linkedin.com/in/shawengineering
 

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