Editing tolerances for material density or changing to cubic feet number

[eldamino1]

I'm re-learning Inventor (2014), been a lo-oong while since I've used it, I primarily use AutoCAD 2014 and 3ds Max but I have a specific work-related problem I'm trying to solve which Inventor seems to have the tools for.

I need to calculate the COG and total weight of a simplified freeform 3D shape assembly, curved sides, tapered top, covers about a 24'x30' area. For the central section of this assembly, I have a volume I am trying to apply a custom pounds per cubic inch density to, this density was calculated and checked to give very close results to the total weight of a complex aluminum tubing assembly that will be built within this volume. I now want to apply this density number to several new shapes ongoing. Modeling the complete aluminum rec. tubing assembly accurately for the central shape of every new design is time-consuming and the customer doesn't have the funds for that so this is a work-around to get close results.

I have created a new material for this pupose, and my density number is .0005154 lbs per cu. in. However, I cannot set the tolerance in the materials to lower than three decimal places below zero, so I'm stuck at .001 which is nearly twice what reality is, and skews the results as the other objects in the assembly are able to be set to accurate weights as they use higher numbers, or existing material densities. There's a second part of this problem that depends on me getting accurate weights and COG.

I have seen forum posts asking about this, and response from the development team saying they would "look into it" but nothing further. I cannot find anything in the documentation on changing this tolerance setting, so am thinking I'm stuck?

However, if there's a way to change the density to pounds per cubic foot, that number is high enough that I believe I can use it to get close to what I need. But I cannot find any documentation on changing that setting either, if it's even possible.

As an alternate, I think I could do a properties override and calculate the weight manually by checking the C.I. in the program and doing the math, but I have not been able to get the override to work by trying to enter the calculated weight for the shape. Any direction on this would be greatly appreciated, if I can get this to work then I can see about the second part of my question, relating to bouyancy and displacement. Thank you, Dan

[johnsonshiue · Accepted solution]

Hi! I think this can be done easily. Go to Material Browser and click on the folder button on the lower left corner -> Set Display Units. I believe there is an option for English ft.

For showing more decimal points, you can also change it in Tools -> Document Settings -> Units -> Model Dimension Display.

Thanks!

[eldamino1]

Thank you very much for this information. I will try both of your recommendations later today, and get back to you on the results. Very much appreciated! Dan