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solidmecman (Mechanical) (OP)
19 Dec 05 16:52
1.) Do a lot of people create their parts using 'surfaces' and then fill the surfaces in to make a solid body?  or is it a better idea to just use extruded boss's, etc. to create a solid body right away?

2.) What are the main uses of Surfaces?

3.) Is Surfaces one of Solidworks big plus's compared to other 3d CAD software?

MadMango (Mechanical)
19 Dec 05 17:10
My two cents...

1) It depends on the type of work a particular user is doing with SolidWorks.  In my field of work, I have never (never, ever) had the need to work with surfaces.  Others will only work with surfaces.  In regards to surfaces or solids and which is "better", it depends on the type of parts you are creating.  Each method has their place.

2) Swoopy, free-form parts like designer shapoo bottles, airfoils, propellers, organic shapes, features that cannot be obtains by simple extrudes and cuts.

3) No.  Most other mid-range CAD has surfaces as well.

"I think there is a world market for maybe five computers."
Thomas Watson, chairman of IBM, 1943.
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solidmecman (Mechanical) (OP)
19 Dec 05 17:23
see for me, all the parts I make in solidworks need to be dimensioned very precisly so my machinist can cut the parts.  Surfaces don't seem to dictate how 'thick' the surface is, in fact the definition of a surface I read is 'infinately thin', so there is no dimension to the thickness.  If I was making say a bottle that was hollow in the center, I would probably do a round extruded boss, then do a round extruded cut to hollow it out, this way I can dimension exactly how 'thick' the wall of the bottle is, with a surface it doesn't seem to care how thick the walls are.  So that's why I find it odd why you would want to use a surface, because everything I can think of needs to have some sort of dimensioned 'thickness' when it is manufactured.  One cool thing I see about surfaces is that you can make a surface with an open profile or scetch whereas a solid body would need to be closed before sweeping, lofting, extruding, cutting, etc..
SBaugh (Mechanical)
19 Dec 05 17:37
SUrfacing is great to get you to a point Solid modeling will not allow you to. Surfaces don't have to be free flowing then can be planar, etc... Eventually though you will have to get your Surface model to a solid to do anything with it.

My Bionicle model was complex and the surfacing was outrageous... but the finished product was worth it.


Scott Baugh, CSWP

ctopher (Mechanical)
19 Dec 05 17:58
For most users, surfaces are not nessesary. Solids will do fine. If I were designing car bodies or aircraft skins, surfaces would be perfect.

Systems Analyst
SolidWorks/PDMWorks 05
AutoCAD 05
ctopher's home site (updated 06-21-05)

Gildashard (Mechanical)
19 Dec 05 18:18
I usually start with Solids and create surfaces to cut the solid as needed to get the shape I'm after. Sometimes I may split and delete faces which turns the solid into one big surface body, then construct some surfaces and knit it back up into a solid. I avoid this if I can though due to it losing body information like color.


UG NX2.02.2 on Win2000 SP3
SolidWorks 2005 SP5.0 on WinXP SP2
SolidWorks 2006 SP1.0 on WinXP SP2

Theophilus (Mechanical)
19 Dec 05 22:05
I use surfaces for complex geometry as an industrial designer all the time.  The answer to the question depends on the final outcome necessary, since I use the most efficient way I can figure out to get something done.

Jeff Mowry
Reality is no respecter of good intentions.

solidmecman (Mechanical) (OP)
19 Dec 05 23:47
okay lets say you are using surfaces to make the wing of an aircraft, don't you still want to specify how thick the 'surface' (ie. Skin) of the wing is?  With surfaces all I see is just a thin face, and there isn't a parameter for the thickness of the surface, so therefore if you wanted to take that model to manufacture, how do you specify how thick the surface (skin) of the wing has to be?
SBaugh (Mechanical)
20 Dec 05 2:04
You can thicken the surface by INsert\Base/Boss thicken. But you can use Surfaces to design with and in the end you can knit them together and form a solid. It can even be a thickness. But a surface itself does not have mass, hence the term "Surface". If take some classes or look on the web you will find a tutorial that someone posted here last year I believe.

You need to try and use it when you are not working on your work stuff, so you will understand how it is used. Explaining how we use it is not going to truly help you I don't think. Make a 6 sided block using Surfaces.

I have made the 6-sided block in this avi file. Check it out and see if you can duplicate it - You will have to Download the codec from -

Starting out simple is the fastest way at understanding SW. Surfacing is an advanced feature in the software. Hopefully you full understnading on the basics of the software now.


Scott Baugh, CSWP

solidmecman (Mechanical) (OP)
20 Dec 05 8:11
yeah I have been working threw the SolidProfessor cds' I have found them very helpful, some of the features like Flexing, etc. are really way more than I think I will ever need or use..
Gildashard (Mechanical)
20 Dec 05 9:45
Look through the Solidworks tutorials, there is a surfacing example or two there.


UG NX2.02.2 on Win2000 SP3
SolidWorks 2005 SP5.0 on WinXP SP2
SolidWorks 2006 SP1.0 on WinXP SP2

Theophilus (Mechanical)
20 Dec 05 16:59
A surface is theoretical--you cannot have a true surface as defined within 3D modeling in real, tangible form.  It's truly without thickness.  So to define an aircraft skin thickness in true form, you would need to model it as a solid.  You can start with surfaces and thicken them, as noted above, but you will eventually need the "third" dimension to turn the theoretical into the real.

Jeff Mowry
Reality is no respecter of good intentions.

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