Surfacing for everyday modeling

I'm doing some research for a user group presentation, and I'm just
curious about how most folks use surfacing in everyday modeling. I know
"everyday modeling" means different things to different people, but I'm
aiming at the group of folks that doesn't necessarily do a ton of
complex shapes.

Do you use things like:

- replace face
- move face
- fill surface
- extend / trim surface
- delete face
- untrim
- delete hole
- move body
- delete body
- cut with surface
- up to surface end condition
- up to body end condition
- loft surface
- loft a solid between surface bodies
- ruled surface
- radiate surface
- etc...

Basically anything vaguely interesting surrounding working with
surfaces.

Thanks!

Matt

 

However, a 1 doesn't mean I can do without it, it just means I don't
use it alot, but when I need it I need it bad.

My present work is primarily machine parts which are by and large
prismatic. Surfaces however make excellent sources of stable reference
geometry that can be extracted and kept stable early in the feature
tree as recommended by Ed Eaton.

 

Hi, Matt,
1 on a scale of 1-10
Never had a need for it

 

That's interesting too. What type of design do you do?

Are you familiar with the commands and just don't see an application or
do you not use them because you're not sure what they do?

Do you ever use solids to fill in little nicks in a part?

Do you ever find yourself closing a sketch with a bunch of lines that
don't really matter just so you can extrude a solid or making a cut
extrude to clean up a face?

 

I've done more surfacing lately than ever before, so just because I'm
not using something may not be because it's not just terribly useful . .
.. it may be because I don't understand how to use it (yet). Those are
tagged with a Zero. SO, also on a scale of 1-10 where 10 is likeliest
to be used on a part for which surfacing is necessary:

3 - replace face
0 - move face (don't know how to use it)
5 - fill surface
8 - extend / trim surface
7 - delete face
4 - untrim
0 - delete hole
0 - move body
1 - delete body
6 - cut with surface
9 - up to surface end condition
9 - up to body end condition
9 - loft surface
0 - loft a solid between surface bodies
4 - ruled surface
3 - radiate surface

One thing you didn't mention was Hide Body. I find that to be very
useful to be able to see what I'm doing, and sometimes useful to show
the end condition. Probability of usage (whether temporatily or
permanently) approximately 8. Also the Combine (Bodies) function is
quite useful when using a combination of solid modelling and surfacing
techniques. I'd call that a 7.

'Sporky'

 

Thanks, Spork.

I'm trying to distinguish between body functions and surface functions,
even though I know I listed a couple like up to, delete and move body

Show/Hide body is something I use on a per minute basis, can't imagine
why I left it out. I try to avoid the need for a Combine, but still
have to use it sometimes.

The discussion about how SW handles "bodies" is at least as interesting
as the surfacing discussion. Someone else is actually presenting that
discussion too. I hope to learn a bit about that so I don't have to
keep learning the hard way!

7 - replace face (when it works, it simplifies things a lot)
1 - move face (best for imported solids)
9 - fill surface (this is like a magic wand, I love this one)
8 - extend / trim surface (extending is sometimes quirky)
7 - delete face (this is another underused gem)
6 - untrim (sometimes this will get you out of a bind easily)
4 - delete hole (really just untrim)
4 - move body (when cheating counts and offset doesn't work)
2 - delete body (not sure about why/when you should use this)
7 - cut with surface (a huge favorite rather than extrude up to)
9 - up to surface end condition (sometimes you gotta use it)
4 - up to body end condition (when up to next doesn't work)
9 - loft surface (use this frequently)
6 - loft a solid between surface bodies (usually as a workaround)
8 - ruled surface (quirky, but essential)
2 - radiate surface (when radiate won't work)

 

That's a big one.

My design work tends to be plastic parts, and even if the part isn't a
crazy shape overall, there's always some funky transition which can't be
made with extrudes. I've found with plastics that the ruled surfaces
are essential, even if they don't really work that well.

I should also add to the list things like Thicken, Knit and Hide Body as
Spork pointed out.

 

matt wrote (my comments interspersed):

replace face (when it works, it simplifies things a lot)
When you can use it it's magical, wonderful, indespensible.

move face (best for imported solids)
I'll have to look into this one. SolidWorks Help isn't very helpful.

fill surface (this is like a magic wand, I love this one)
I like it too, when I can use it, which always seems to be not nearly
as often as I'd like to use it.

extend / trim surface (extending is sometimes quirky)
Quirky it is at times, but Trim less so than Extend. And Extend I use
almost as much as Trim.

delete face (this is another underused gem)
This is good, but Delete with Replace or Delete with Patch doesn't seem
to work very often.

untrim (sometimes this will get you out of a bind easily)
This one is Black Magic -- don't understand it at all, but it works
wonders at times.

delete hole (really just untrim)
Never even heard of it -- need to look into it.

move body (when cheating counts and offset doesn't work)
Have seen many references to this lately, and I still don't have a
clue.

delete body (not sure about why/when you should use this)
Ditto, but I wonder if one can use it instead of Hide Body when you
actually want to do it permanently.

cut with surface (a huge favorite rather than extrude up to)
INSTEAD OF? How?

up to surface end condition (sometimes you gotta use it)
Yeth, but am often frustrated by the inability to use if the surface
doesn't extend beyond the sketch. I often have to use Extend surface or
Ruled surface to make the boundary bigger.

up to body end condition (when up to next doesn't work)
I never think of "up to next" as something preferable to "up to body"
-- can't figure how that works, but I'll try it. I do sometimes wish
there was an "offset from body".

loft surface (use this frequently)
Goes without saying, but so many options are confusing, and many of
them very quirky (often much better than lofting a closed profile into a
solid, however). I'm NOT complaining about too many options . . . just
that there's too little explanation, as is true with almost ALL of the
surfacing options.

loft a solid between surface bodies (usually as a workaround)
Didn't know it was possible.

ruled surface (quirky, but essential)
Extremely useful -- I find it strange that you can use a face of a
solid with this option, but not with Extend (have to Offset with zero
distance first to use Extend).

radiate surface (when radiate won't work)
Huh? Nothing else does what this does . . . I don't know what it could
possibly substitute for.

 

You can move or angle the face of a solid. Nice for removing draft or
actually modifying imported geometry.

I think this one requires that you understand how the brep works.
You're basically asking SW to cover over faces with the underlying
(untrimmed 4 sided nurbs) geometry of the original face.

Non-analytical faces are based on nurbs surfaces which are 4 sided, then
trimmed to fit. This is how the Fill surface and the Shape command
work, by making a 4 sided patch and trimming it to fit. the 4 sided
surface is there in the background, almost like a feature history.
Untrimming just reveals the base surface.

There's not a button for this one. You just select an open edge of a
surface and hit delete. It will ask if you want to delete the feature
or a hole.

It's the equivalent of move part in an assembly. SW06 will make this
largely obsolete by using mates to position multibodies.

I guess what I'm wondering is why would you do it permanently? The only
thing I can think is that SW handles solid bodies poorly, and things
flow better if you only have a single solid body.

Instead of making a big sketch and cutting up to a surface, it's better
if you can just cut with the surface directly. Sometimes you have to
have multiple bodies and restrict the cut to a single body. Also.
Replace face can add and/or remove material sometimes in the same way
cut with surface removes it.

I've been just the opposite. I used up to body a few times on my most
recent job. The way it colors the body is very distracting, and makes
everything hard to see, like trying to read the print on a light bulb
when it's turned on. Up to next does have some strange things that it
does, but if you know to expect them, then its cool.

The ones to worry about are the end conditions and GC side tangency.
Anything else I usually use defaults.

Great workaround for when a thicken won't work. Offset or copy a
surface, then loft between the copy and the original. If that doesn't
work then you need to build the side faces all the way around with a
surface loft then knit.

I wish you could use a sketch, but it needs an edge.

Sorry for the typo. I meant when the ruled surface won't work,
sometimes you can substitute a radiate.

 

John,

I've got to admit, that's new to me. Other than "lofted bends", I've
never associated surfacing with sheetmetal. Do you have a sample part
you could share that shows this technique? What types of cuts are you
talking about?

Thanks!

Matt

 

Thicken and Knit. Don't think they were on the list, but they would be
a 9. In fact offset surface wasn't there and that is the basic means
to get a copy of a face. I do recall some sort of surface option with
shell as well. I think it happens when things go awry.

I've been working on large sprayed up concrete structures. Don't have
to worry about draft but definitely freeform at times.

 

Actually, it's not permanent. You can delete the "delete body" and your
bodies are back again! I find it useful to semi-permanently hide the
surfaces and bodies that you used to build the part, once you're finished
with them.

Jerry Steiger
Tripod Data Systems
"take the garbage out, dear"

 

Oh boy, forgot one really big one. The Atomic Bomb of Fillets (E.E.'s
nomeclature).

Take one overly complex intersection of edges.
Extrude some simple geometry out from that intersection in order to
consume it.
Create fillets up to the extruded geometry.
Use fill surface to "patch" the consumed area and terminations of the
new fillets..
Use that surface again to trim away the extrustion.

This is not a single SW feature, but a combination of operations that
pretty much guarantee's that SW can fillet any geometry. In fact it is
conceivable that this method can join a fillet to a chamfer and a round
to a fillet.

 

One other issue.

Try to differentiate any operations with these that are documented in
SW literature (Help, Training Manuals, KB, VAR communications, etc. )
from those cooked up solely by users. The reason is that SW will
sometimes pull the undocumented feature lever when they take away a
technique that we use just because it is not explicitly in the
documentation. I attribute this to the fact that sometimes the people
that define what SW is, are not aware of how SW is used. I'm talking
about the programming level mostly because that is several levels of
awareness away from the user.

 

Right. What I'm wondering is why you would use this Delete Body feature
to begin with other than just to eliminate the affects of multiple solid
bodies (mainly SW miscalculating the feature scope, the blinding bright
neon previews and the rib and mirror features always asking which body
to add to). I haven't had the patience yet to test how it affects
performance vs Hide Bodies.

Matt

 

Good one. I just think of this as the Fill Surface, but you're right it
does combine Split Line with Delete Face (or a solid cut).

 

....

My apologies, yes, you're right. It goes in the category of features
you can use to edit imports that don't get much press.

Good tip, I like that.

Sometimes, depends on if you're using the "same face" or "tangent"
option. Tangent seems to make more stable faces, but doesn't join them
well if you're trying to extend adjacent edges or an entire face.

The presentation I'm gearing up for is how solids and surfaces interact,
and the Delete and Patch function is a great way to demonstrate how SW
uses surfaces in the background to edit solids. Also, the Delete Face
by itself is the way to go from a solid to a surface.

more like untrim, I think. I don't think this works on solids, only
surface.

I like all of the different methods you can use. I can usually get it
to give me something, but they're not always well made. I keep trying
to report bugs on this because it would be great to see this feature
mature.

I have a feeling this has a lot of function in common with the ruled
surface. They seem to handle non-tangent corners differently.

Thanks for the input!

Matt

 

I guess I'm part of the minority that doesn't use them as such. I did have
one occasion once that required a bit of surfacing work, but I had to get
help. No other time have I needed them.

Now, that being said, what I don't know about hardly lets me use it when
needed. How do I know when I need them???

Most of what I design is based on metal fabrication, such as structural
shapes, sheet metal, wlmts, castings, etc. I design custom machinery for
building and handling cars, trucks, SUV's, etc. Do I NEED to use surfacing
techniques to do my job? No - I have done just fine without them. Would
they ever help in some way? Maybe, can't answer that one definitively. I
would be a fool to state that there will never be surfacing in my day.

So, bottom line is that I haven't seen the need for it yet, but I also
haven't look real hard either.

WT

 

Matt,

My list is pretty close to yours except there are a couple of functions that
I hardly ever use.

2 - replace face
1 - move face
9 - fill surface
8 - extend / trim surface
7 - delete face
6 - untrim
6 - delete hole
1 - move body
4 - delete body
6 - cut with surface
9 - up to surface end condition
7 - up to body end condition
9 - loft surface
2 - loft a solid between surface bodies
1 - ruled surface
1 - radiate surface

What do you use ruled surfaces for?

Jerry Steiger
Tripod Data Systems
"take the garbage out, dear"

 

Most of my work consists of standard extrusions and sheet metal.
These are used on G5 code cnc machines and sheetmetal punching and folding
machines.
Simple and cheap, lol