Mastercam: surfaces vs. solids

Among one of my previous threads I asked the question of why we use solids. I was given some good answers, but among them was a comment that it was superior to surface creation. I'm encountering more surface generation in the programs at my current shop and am wondering whether there is a distinction between the two.

the comment made it seem that surfaces were of an antiquated cam age and that solids are the wave of the future. Is this true? Why would one opt to use solids over surfaces?

I have minimal experience with either but the little I do has made solid generation seem like an easier task-once you know a few solid commands you can get farther in geometry creation than if you knew just a few surface commands.

What is your insight into this? Do you prefer surfaces or solids?

I have used Mastercam for years, and there isn't a part that I can't describe in surfaces. Look at the enclosed examples, and tell me how you would describe them in solids.

Yeah I have no idea how I would do that for either, actually

Bruce Nelson said:

View attachment 160928

Look at the enclosed examples, and tell me how you would describe them in solids.

Click to expand...

one word:
Solidworks

dang nice work in MC, BTW!!!


solids are a HUGE help in creating corner/fillet radii. Surfaces can't hold a candle to the speed and power via solid. MC or Solidworks.
At the end of the day there are good used for both surf and solids. either / or is not the question.

For this kind of parts, surfaces are the best way. But if you convert it to solid you can alter it much easier.

Rbpercussion said:

Among one of my previous threads I asked the question of why we use solids. I was given some good answers, but among them was a comment that it was superior to surface creation. I'm encountering more surface generation in the programs at my current shop and am wondering whether there is a distinction between the two.

the comment made it seem that surfaces were of an antiquated cam age and that solids are the wave of the future. Is this true? Why would one opt to use solids over surfaces?

I have minimal experience with either but the little I do has made solid generation seem like an easier task-once you know a few solid commands you can get farther in geometry creation than if you knew just a few surface commands.

What is your insight into this? Do you prefer surfaces or solids?

Click to expand...

Solids ARE the now not just the wave of the future. I have been using NX since it was originally UG and I think our company started at UG v9 or 10. All the data we receive from customers for building molds is typically in native NX or Solidworks files but we also take in a lot of STEP files as well. We create large complex molds designs which are associative and parametric. Assemblies allow us to create complex designs and easily implement any changes as well as simulate motion to make sure timings and clearances are met.

I believe your opinion is correct in that solids have much more capability than surfaces. Good solid modelers should have anything you need to model your part, can do everything surfacing can and much more such as boolean functions and complex assemblies. Some CAM programs do not include decent modeling because they are focused on CAM and can get by with minimal modeling, often just basic functions for the purpose of manipulating tool path containment. It's up to you to decide "how much" CAM program to purchase depending on your needs. There are many solid programs out there so you'll need to decide what's a good fit for you; simple widgets, complex widgets, part assemblies... Really, basic solid modeling can be done with a lot of different programs. You'll have to keep asking questions, gather more opinions and then perhaps attend some demos. Don't be afraid to bring your own parts and talk about up-front pricing as well as yearly maintenance.

MY main irk with surfaces is they always seem to corrupt upon reopening a program...

When I FIRST learned to 3D machine I would import a solid and assumed you couldn't select an individual surface from it... I later found the button to do that :P ... but to circumvent that, I'd break apart the solid into surfaces and delete all the stuff I wasn't machining so I could highlight all of one level for machining and be done with it... after you post, save it, and come back to it later... often times you'll have "corrupt surfaces" that don't reimport onto the screen... which is REALLY frustrating when you're just changing one little thing that didn't come out right...

I've found with solids this NEVER happens... so that's why I basically ONLY use surfaces for the "fill holes" function...

EDIT: I was assuming you were working from an imported STEP file or parasolid... I have NO IDEA why someone would use CAM software to design a 3D CAD part... that is beyond me if that's what you're referring to... use the right tool for the job... if this is really the question, that's akin to asking why people don't use mills for round parts... it can be done... don't get me wrong... but WHY???

Charlie maSheen said:

MY main irk with surfaces is they always seem to corrupt upon reopening a program...

When I FIRST learned to 3D machine I would import a solid and assumed you couldn't select an individual surface from it... I later found the button to do that :P ... but to circumvent that, I'd break apart the solid into surfaces and delete all the stuff I wasn't machining so I could highlight all of one level for machining and be done with it... after you post, save it, and come back to it later... often times you'll have "corrupt surfaces" that don't reimport onto the screen... which is REALLY frustrating when you're just changing one little thing that didn't come out right...

I've found with solids this NEVER happens... so that's why I basically ONLY use surfaces for the "fill holes" function...

EDIT: I was assuming you were working from an imported STEP file or parasolid... I have NO IDEA why someone would use CAM software to design a 3D CAD part... that is beyond me if that's what you're referring to... use the right tool for the job... if this is really the question, that's akin to asking why people don't use mills for round parts... it can be done... don't get me wrong... but WHY???

Click to expand...

Well, taking that ^ out of context. Why not? A simple 'dumb' solid is pretty easy IMO with the better (read more expensive) CAM packages. I do lots and lots of solid modeling in mine. Am I going to design a full assembly with hardware and such, no way. But I certainly use the modeling features of my cam package all the time. For me it runs the gamut of filleting 1 single corner (or modifying the fillet) to modeling a somewhat complex fixture imported onto/into a vise model so I can run collision checking on the 5axis mill.