Solids vs. surfaces

[WingNutz]

I read somewhere that solids was preferred over surfaces for toolpathing 3d contours. Why is that? What are the benefits?

[Matt Berube]

I think the advantage is that a solid can be selected as "drive" in a single click where as to select all your surfaces would require a selection window or one of many other options...

There are limitations though...

For example, select a few faces for "drive" and a few faces for "check" on a single solid... MC seems to be confused by this activity...

I prefer to use solids generally but as soon as I run into a snag I just create surfaces from the solid and use those instead.

[lovecnc2003]

thanks

[ObrienDave]

Another advantage to using a solid is when evaluating the toolpath, Mcam can tell when a solid 'face' is under another one thereby ignoring it.
It makes for quicker toolpath generation for parts or molds that have thousands of 'faces' or more.
You won't notice the speed increase on very simple parts of a few hundred faces or less.
I worked on molds that had up to 100,000 faces and could take hours to generate one path.
So I have the habit of using ONLY the surfaces I need to generate the part.
Time is money and all that BS.

[cadcam]

Some other thoughts are that Surface models are not water tight models in lots of cases you can get an Iges model that has gaps in between surfaces.

Solids are water tight models no duplicates no gaps for the tool to jump in to.

Also have you tried getting wire frame from a surface model ther are more splines then needed there are lots of dups in he edges. you do not get this you get clean wire ready to cut from.

Also review link.http://www.mastercam-cadcam.com/vide...dadvantage.wmv

Opps I miss spelled SOLIDS.