topic Re: looking for a way to calculate external surface area of a complex 3d solid in AutoCAD Forum

looking for a way to calculate external surface area of a complex 3d solid

mvr_asp — Thu, 12 Sep 2024 22:30:40 GMT

Hi there all

I have a complex machine drawn in 3d solids in AutoCAD.

I need to provide the approximate external surface area to be painted, this machine looks like a large crane crossed with a bridge, so it has many complex interior and exterior surfaces.

is there a lisp program or otherwise someone could please suggest to make my like easier trying to estimate the surface area?

I was thinking of something like the shrink wrap program for 2d, however for 3d solids.

I don't mind even if we need to use other software, but would prefer to stay with AutoCAD if we can

Re: looking for a way to calculate external surface area of a complex 3d solid

Washingtonn — Fri, 13 Sep 2024 00:08:39 GMT

You might try using the BLENDER software. Could you post a partial of the solids file?

Re: looking for a way to calculate external surface area of a complex 3d solid

mvr_asp — Fri, 13 Sep 2024 01:12:47 GMT

hi thanks for your suggestion, i will put it to the team.

i cant supply a sample of the model unfortunately, besides being quite large, i don't have permission to share it.

Re: looking for a way to calculate external surface area of a complex 3d solid

leeminardi — Fri, 13 Sep 2024 12:48:06 GMT

How about the AREA command! Just give the command followed by an O (object) and select the solid. Fast, easy and accurate.

Re: looking for a way to calculate external surface area of a complex 3d solid

mvr_asp — Sun, 15 Sep 2024 23:10:29 GMT

Thanks for your suggestion, yes something like that would be very accurate and easy, however I only need the outside surface area of a very large machine, for painting.

so inside walls do not need painting, or calculating.

however i will give your suggestion some thought

Re: looking for a way to calculate external surface area of a complex 3d solid

leeminardi — Mon, 16 Sep 2024 12:25:58 GMT

It would be helpful to have more information about the "complex 3d solid". I don't know if it would be feasible to use surfsculpt to fill the voids in the solid so that you have a solid that only has the external surfaces. When using surfsculpt it may be necessary to "plug" holes in the solid to yield a watertight shape. Keep in mind that the plugs do not need to exactly fit the holes and may extend beyond the hole openings.

Re: looking for a way to calculate external surface area of a complex 3d solid

autoid374ceb4990 — Mon, 16 Sep 2024 15:05:52 GMT

How about posting some screen shots of this complex machine? Could you post a front, right side, left side, and rear view?

Re: looking for a way to calculate external surface area of a complex 3d solid

mvr_asp — Mon, 16 Sep 2024 21:41:44 GMT

hi there, I am not sure I can share a screen shot, however this is a google image from street view.

basically we have this in 3d, we need to work out how much paint to use to paint it.

Re: looking for a way to calculate external surface area of a complex 3d solid

Washingtonn — Mon, 16 Sep 2024 22:38:44 GMT

It looks like it has been painted before....simply find out who did the first paint job and ask them how much paint they used. I would imagine that with cleanup, over spray, touch-ups and spills, the calculation for surface area per Lee's suggestion would end up being fairly close to what will be needed. Paint costs will be much less of a concern than the labor needed - scaffolding to access the surfaces and the actual painting.

Extra paint is not a bad thing when you need to handle areas prone to rusting and wear.

Re: looking for a way to calculate external surface area of a complex 3d solid

mvr_asp — Tue, 17 Sep 2024 01:32:54 GMT

yes it has been painted before, in 1980.

Re: looking for a way to calculate external surface area of a complex 3d solid

Tomislav.Golubovic — Tue, 17 Sep 2024 04:02:31 GMT

Fusion should be able to do it. You'll need to import a 3D solid and get Properties of it.

https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/How-to-calculate-external-surface-area-of-a-body-in-Fusion-360.html

Re: looking for a way to calculate external surface area of a complex 3d solid

SEANT61 — Tue, 17 Sep 2024 05:20:59 GMT

Yes, that’s a complex 3dSolid alright.

The screencast attached demonstrates AutoCAD’s AREA command, as suggested by @leeminardi, with some additional steps to accommodate more complex solids. This post/attachment is for general reference – which is to say that I would not necessarily recommend it for the project referenced by the OP. It may be possible, but I wouldn't want to do it.

NOTE: The XBOX Gaming screen capture feature does not pick up AutoCAD drop down menus, apparently. At that midpoint, I used the SOLIDEDIT-COPYFACES command.

Re: looking for a way to calculate external surface area of a complex 3d solid

autoid374ceb4990 — Tue, 17 Sep 2024 14:22:32 GMT

You cannot share the drawing and you cannot furnish screen shots of a front view. Can you furnish a DWG of one or two of the more complex 3D SOLIDS? Are there any other entity types that make up the area you are interested in?

Re: looking for a way to calculate external surface area of a complex 3d solid

TheCADnoob — Tue, 17 Sep 2024 14:59:00 GMT

Have you tried providing drawings to a coating contractor? They may have methods for determining things like this.

Re: looking for a way to calculate external surface area of a complex 3d solid

mvr_asp — Tue, 17 Sep 2024 23:03:50 GMT

I will see what i can do

Re: looking for a way to calculate external surface area of a complex 3d solid

mvr_asp — Tue, 17 Sep 2024 23:05:22 GMT

yes that is the path we are looking at