# Set unit/solid body exect weight in kg/lbs

I tried to find anything about it but unsuccessful.

Can I set up in Rhino somehow exact weight for the solid?
Say, I have a cube with weight 10kg and another body rectangular shape with weight 20kg.
As an illustration - the cargo deck with different items but known weights for each one.

note: the density of the solids is dissimilar but the weight is known.

Is it possible for the specific gravity of the element to be set as a parameter/property of the object/layer and then used in calculation later?

Might not be relevant if the solids are consistent size (ie. nothing much unique to calculate)

My goal is - to play with locations of solids with different dimensions and different weights to receive the position of center gravity in a determined place.
Of course, I can do it in â€śmanual modeâ€ť but rhino can calculate CG by itself for uniform bodies. The trick is to do the same with non-uniform solids.

I suppose you could replace all volumes by new volumes based on one common density and then use `VolumeCentroid` on all new objects.

How about to find the density for 20ft container loaded with fridges, bicycles and timber?
The goal is to receive CG in Rhino without any hand calcs. Grasshopper mb?

Hello - I have an ancient script which works off of Rhino materials - the materials need to have a density assigned and then the script finds the correct density from that:

This is all very crude - you need to specify material density in the material notes in the form

`Density= XX gm/cm^3`

in any of these units:

â€śgm/cm^3â€ť, â€śkg/m^3â€ť, â€ślb/ft^3â€ť, â€ślb/in^3â€ť

If you want to try - MassCentroid_Mat.rvb (13.3 KB)

Save, then drag and drop that rvb file onto Rhino, then use the alias

`MassCentroidâ€™

Good luck!

-Pascal

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Thank for sharing but itâ€™s not what I am looking for.
I am NOT INTERESTED to know the density cause I ALREADY KNOW the weight of the object.
I want to set up already known the weight for a concrete object without playing with real or â€śvirtualâ€ť density in case of non-uniform object.
Say this solid body 1.5mx20mx1.8m weight is 100kg. Point. Another one body 0.5m x 1m x2m is 2000kg. No volume calcs, no density calcs, just: this solid - X kg. Independently from dimensions.