Suface-Offset Problem?

Hi,

If I create a surface-offset in a part, then cut-extrude to that surface
things seem OK. When I then add a hole, counterbore, or even another
cut-extrude thru the part the part gets cut but not the offset deface. It
is like the offset surface cannot be cut by anything.

What am I missing here?

Should not the surface-offset be cut buy another feature?

SW2005 sp3.1

Aron

P.S. I have another part made the same way from a previous version (2005
sp1) that works fine, so this confuses me even more???

 

Surfaces aren't cut by solid features. To cut a surface, you have to
use the "trim" function on the surface toolbar. Still, that's probably
not what you want to do. You probably just want to hide the surface
body.

matt

 

Matt,

How do you hide the surface body? I see only suppress not hide?

Maybe I will try to use the trim surface function.

I am doing something like a shell function, but instaed of the way the shell
function follows the contours of the object, I want to use a sketch and cut
down to an offset surface...it sure is hard to explain a 3D CAD Model in
words!

Or it may just be time for bed! Eyes (and mind) getting sleepy, etc...

Thanks,

Aron

 

If you right mouse click on the surface only, not the face of the solid,
there should be an option for "Hide Body". Or you can right click on
the body in the "Surface Bodies" folder at the top of the tree.

What you're doing is a common use of surfaces. So far it doesn't sound
like you have any reason to trim the surface. The fact that the surface
shows up after you used it for something is kind of like if sketches
showed after they were used by an extrude feature. With surfaces you
have to manually hide them.

matt

 

Matt,

THANKS, I saw the body hide function, and presto that was it!

I do not remember having to do that before, Sometimes its like certain
functions change there default behavior over time (i.e. with each new
service pack)???

-OR- Perhaps I just don't remember things well... I am getting older!

Anyway, thank you again for your help, it worked, I am happy...client will
be happy...

Aron

 

If I may make a suggestion -

I the surface body is used for construction, after the feature that
requires it (in your case, the extrude) you might consider 'deleting
the body'.
This has several advantages:
1) If your model fills up with lots and lots of construction surfaces
it can be a difficult to find the right one in the surfaces folder
2) When doing a tools>check on the model, the report of 'X open
surfaces found' confuses and scares people. It sounds to them like
there is a problem, even though there is not. You can try to take the
time to explain to every subsequent person that works on the model that
it is no big deal, or you can take two seconds to delete the body and
make the issue moot.
3) Frankly, surfaces still freak out a lot of people. If they don't
have to see them in the tree YOU don't have to deal with the panic. At
the very least I try to make one of the last features in the model a
'delete body' to take all of the left-over surfaces out of the
equation.

A little housekeeping pays off downstream.

 

If I may make a suggestion -

I the surface body is used for construction, after the feature that
requires it (in your case, the extrude) you might consider 'deleting
the body'.
This has several advantages:
1) If your model fills up with lots and lots of construction surfaces
it can be a difficult to find the right one in the surfaces folder
2) When doing a tools>check on the model, the report of 'X open
surfaces found' confuses and scares people. It sounds to them like
there is a problem, even though there is not. You can try to take the
time to explain to every subsequent person that works on the model that
it is no big deal, or you can take two seconds to delete the body and
make the issue moot.
3) Frankly, surfaces still freak out a lot of people. If they don't
have to see them in the tree YOU don't have to deal with the panic. At
the very least I try to make one of the last features in the model a
'delete body' to take all of the left-over surfaces out of the
equation.

A little housekeeping pays off downstream.

 

I've had questions about this in the past. Do you delete bodies just as
a housekeeping method? Is there any performance aspect to deleting
rather than hiding? If it's simply organization or housekeeping, well,
everyone has different ways of keeping their house that might not work
for others. I've seen people delete all the mates and sketch relations
in the name of housekeeping. I know that I personally might reuse
surfaces later on, and a delete body would just have to get reordered
down the tree, so I tend to just hide them. Hiding seems to leave
options open, when deleting means you have to go back in the tree to get
the options again.

I might try the delete rather than hide approach in my next surface
model to see if it goes any better than my usual approach.

Matt

 

Usually, I define "A" surface swatches at the top of the feature tree,
and delete tham at the bottom of the feature tree w/ "Delete Bodies".
Copies of "A" swatches and other tool surfaces used "short term" are
deleted after they are used, usually at the end of a folder for a set
of specific product features.

 

Tick,

Thanks for your observations.

I'm not getting an answer to my question, though, so I'm going to ask it
differently.

I'm not concerned that you DO or DON'T delete bodies. I'm concerned
about WHY you do or don't delete bodies. I'm looking to see if someone
has a functional reason other than for organization.

I don't delete bodies. Maybe some people think this is chaotic. The
reason I don't delete is, well, there doesn't seem to be a real reason
to do it, and I find it more convenient.

It would be interesting to do a little test to see if any performance
gains by not having the bodies in the tree after a certain point are
offset by the time it takes to delete the bodies in the first place.
Anyone got some free time and a model with a bunch of surface bodies?

Matt

 

Yes, its partly about housekeeping/ keeping things tidy. But it mostly
comes out of my experiences with passing on data to others, because
even hidden surfaces show up in the folder and it always introduces
questions.

The preformance improvements are for me - I remember a part with about
27 construction surfaces and I spent a LOT of time going through them
to find the right one. Now I delete the ones I know (or strongly
suspect) that I won't need anymore right after they are used, just like
That70sTick.

I am not sure about memory use, rebuild times, etc. I also do not know
what happens on export - if hidden surfaces go along too.

 

Mostly housekeeping. I try to keep my surface feature dependencies as
"local" as possible. Also, I've been burned by poor outgoing
translations caused by accidentally sending out extra surfaces.

For instance, if I have a folder for a set of features for something
named "Snap Undercut", all surfaces generated within that folder are
used only within that folder and cleaned up with "Delete Bodies" at the
end. That way I can blow away an entire folder without removing
surface featuress that are referenced elsewhere.

"Delete Bodies" is almost unnoticeable in terms of regeneragtion time.
Same for offsetting or copying surface bodies in most cases.

 

Would you be willing to look into one the models where you did this, and
run a Feature Statistics and tell how far from the top of the list
(percentage wise) the first Delete Bodies feature is found?

Thanks,

Matt

 

I'll run analysis on some models Monday and post here.

 

A model with 226 features, rebuilds in 56.91 seconds:

Most of the delete bodies are at the very end of the tree mixed in with
sketches and suppressed features. 3 of the last 6 resolved features in
the list were delete bodies.
Out of 8 delete bodies on this model, seven have rebuild times of 0.00.
The only oddball one has a rebuild time of 0.02 - I don't know why.

 

Thanks, Ed, that's interesting. So at least it doesn't cost you
anything. I guess for me the next question is does it gain you
anything. It would likely have a positive effect on the file size,
since it wouldn't have to save that body geometry.

I've never seen surfaces export with the solid unless I selected them
before starting the export.


I understand your explanation about handing things off to other users,
but a "delete body" (something you can see, but it's not there) feature
I would think could cause as many questions as something you can't see
that is there. I don't want to belabor the point, but this is a
question I've had for some time, just haven't taken the time to research
it.

Truthfully I became prejudiced against the feature when I got a model
from someone that started with an imported feature, then started
building over the import, and then had a "delete body" feature which
deleted everything in the model!?! Then he started again. Just as if
he were modeling with the feature manager closed or with a non-history
based modeler.

The only times I've actually used it have been on left over solid bodies
which I didn't want in my model. I've always considered surfaces to be
reference geometry, like planes or sketches. SolidWorks handles surface
bodies much better than it handles solid bodies in what I've seen,
although "why" is another thing I don't understand.

Thanks for the results,

Matt

 

That could be the result of inexperience. Perhaps your colleague meant
to start from scratch and thought he was deleting all the features.
For some unknown reason, he just accepted all of the overhead remaining
in the feautre tree. Don't let the ham-fisted actions of a feckless
ape poison your judgment of this useful feature.

There is a tidy little bit of automation built into SW where if a body
is picked and the "Delete" key is hit, the body is deleted with a
"Delete Bodies" feature. All of the features remain intact.

As far as what is gained, it probably depends on what you typically
model. When modelling organic shapes, getting rid of loose ends that
can tangle up a bunch of features downstream can be valuable,
especially in terms of time (billable hours? looming deadline?) saved
cleaning up a "Tree of Blood" (tm Ed Eaton).

 

Feature Statistics:


257659 Cover 8/28/2005 3:14:35 PM

Features 203, Solids 1, Surfaces 0
Total rebuild time in seconds: 22.31


Time % Time(s) Feature Order

0.00 0.00 Axis -Z0-
0.00 0.00 Axis -Y0-
0.00 0.00 Axis -X0-
0.00 0.00 Plane +8.75 Z
0.07 0.02 Sketch1--DuMay
START OF FOLDER "LAYOUT"
0.00 0.00 000--Dummy Library Feature<1>
0.00 0.00 Skt Position--Pitcher Top LF
0.07 0.02 Skt Guide--Pitcher Top LF
0.00 0.00 Plane Section--Pitcher Top LF
0.07 0.01 Skt Section--Pitcher Top LF
0.00 0.00 Pitcher Top Surface Curves<1>
0.00 0.00 Skt Position--Cover Top Main
0.00 0.00 Skt Guide--Cover Top Main
0.00 0.00 Plane Section--Cover Top Main
0.00 0.00 Skt Section--Cover Top Main
0.00 0.00 Cover Top Main Surface Curves<1>
0.07 0.02 Skt Position--Handle Side-Outside
0.00 0.00 Skt Guide--Handle Side-Outside
0.00 0.00 Plane Section--Handle Side-Outside
0.07 0.01 Skt Section-OUTSIDE--Handle Side-Outside
0.00 0.00 Skt Section-SIDE--Handle Side-Outside
0.00 0.00 Handle-Ridge Outside and Side Surface Curves<1>
0.00 0.00 DEF Pitcher Outside--Surface-Imported1
0.21 0.05 DEF Pitcher Top--Surface-Sweep1
0.00 0.00 DEF Cover Top--Surface-Sweep2
0.35 0.08 DEF Handle Side--Surface-Sweep2
0.14 0.03 DEF Handle Outside--Surface-Sweep1
0.00 0.00 DEF Spout Cut-in 18Jul2005--Surface-Imported1
END OF FOLDER "LAYOUT"

START OF FOLDER "Main Body"
0.07 0.02 Body-Move/Copy2
2.38 0.53 Surface-Trim3
0.00 0.00 Thicken1
0.35 0.08 Body-Move/Copy3
1.47 0.33 Surface-Trim4
3.01 0.67 Surface-Trim5
4.07 0.91 Surface-Trim6
0.70 0.16 Thicken3
0.77 0.17 Perimeter--Draft1
END OF FOLDER "Main Body"

0.14 0.03 Sketch11
0.42 0.09 Spout Passage--Cut-Extrude1
0.70 0.16 Fillet5
0.84 0.19 Fillet4

START OF FOLDER "Thumb Divot Control Lines"
0.49 0.11 Skt Position--Thumb Divot
1.12 0.25 Skt Guide--Thumb Divot
0.00 0.00 Plane Section--Thumb Divot
0.07 0.01 Skt Section--Thumb Divot
END OF FOLDER "Thumb Divot Control Lines"

START OF FOLDER "Thumb Divot"
0.00 0.00 Sketch5
0.00 0.00 Surface-Sweep1
0.14 0.03 Surface-Sweep2
0.07 0.01 Surface-Knit1
0.63 0.14 SurfaceCut1
0.00 0.00 Body-Delete1
END OF FOLDER "Thumb Divot"

1.26 0.28 Shell1--FIRST

START OF FOLDER "Spout Cover Integration"
0.00 0.00 Skt Spout Pin Position
0.00 0.00 Axis Spout Pin
0.00 0.00 Plane6
0.28 0.06 Sketch47
0.00 0.00 Spout Clearance--Surface-Revolve1
0.07 0.02 Sketch42
0.00 0.00 Surface-Extrude1
0.00 0.00 Sketch43
0.00 0.00 Surface-Plane1
0.00 0.00 Mirror3
0.14 0.03 Surface-Trim10
2.66 0.59 SurfaceCut5
0.21 0.05 Skt Pivot Snap Layout
0.00 0.00 Axis5 Defining Draft Plane
0.00 0.00 Plane7 Draft Neu
0.49 0.11 Draft14
0.49 0.11 Draft13
0.21 0.05 Draft16
0.14 0.03 Sketch48
1.26 0.28 Cut-Extrude7
15.55 3.47 DeleteFace1
0.00 0.00 Plane10 Draft Neu
0.00 0.00 Plane11 Draft Neu
0.21 0.05 Draft19
0.07 0.01 Draft20
0.28 0.06 Draft21
0.07 0.01 Draft22
0.35 0.08 Fillet29
0.42 0.09 Fillet30
0.42 0.09 Fillet31
0.35 0.08 Fillet32
0.07 0.01 Fillet22
0.00 0.00 Fillet23
0.21 0.05 Fillet24
0.00 0.00 Body-Delete5


START OF FOLDER "Toroid Lid Seat"
0.07 0.02 Skt Outline Defining Circle
0.00 0.00 Skt Seat Axis Plane Defn
0.00 0.00 Plane2
0.00 0.00 Axis1
0.00 0.00 Sketch15
0.00 0.00 Toroid Seat--Surface-Revolve1
0.00 0.00 Axis Seat Toroid
0.00 0.00 Sketch18
0.00 0.00 Backstop--Surface-Extrude1
0.00 0.00 Surface-Offset15 Backstop Copy
0.77 0.17 Surface-Trim7
0.00 0.00 Surface-Offset16
0.21 0.05 Surface-Trim23
0.07 0.01 CompCurve1
0.00 0.00 3DSketch4
0.00 0.00 Plane9
0.07 0.02 Sketch51
1.19 0.27 Surface-Sweep3
0.35 0.08 Ruled Surface1
0.28 0.06 Surface-Knit3
1.68 0.38 SurfaceCut2
5.04 1.13 SurfaceCut6
0.00 0.00 Plane3 Z-Draft Backstop
0.70 0.16 Draft9
0.00 0.00 Skt Lid Stalk
0.63 0.14 Sketch17
0.56 0.13 Cut-Extrude3
0.42 0.09 Draft18
0.00 0.00 Body-Delete2

START OF FOLDER "Guide Fins"
0.00 0.00 Skt Pin Start-Finish Positions
0.14 0.03 Skt Tracks C-L
0.00 0.00 Plane--Guide Fin Face
0.07 0.01 Skt Rear Track
0.07 0.02 Skt Front Track
0.49 0.11 Surface-Offset1
0.35 0.08 Skt Track Fin Outline
0.00 0.00 Extrude1
0.21 0.05 Sketch24
0.28 0.06 Cut-Extrude4
0.14 0.03 Sketch28 Keyhole
0.98 0.22 Keyhole Cut-Extrude7
0.07 0.01 3DSketch2
0.00 0.00 Plane3 Z-draft
0.07 0.02 Draft1 Web Face
0.28 0.06 Shell1
0.07 0.01 Sketch25
0.07 0.02 Cut-Extrude5
0.07 0.01 Sketch26
0.07 0.02 Extrude2
0.07 0.02 Sketch27
0.07 0.01 Extrude3
0.07 0.02 Sketch29
0.14 0.03 Extrude-Thin1 Rib
0.07 0.02 Sketch31
0.14 0.03 Extrude-Thin2 Rib
0.00 0.00 Sketch32
0.21 0.05 Extrude-Thin3 Rib
0.00 0.00 Sketch34
0.21 0.05 Extrude-Thin5 Rib
0.00 0.00 Sketch35
0.14 0.03 Extrude-Thin6 Rib
0.00 0.00 Sketch36
0.21 0.05 Extrude-Thin7 Rib
0.42 0.09 SurfaceCut4
0.00 0.00 Body-Delete3
0.14 0.03 Draft2
0.14 0.03 Draft3
0.35 0.08 Draft4
0.07 0.02 Draft5
0.14 0.03 Draft6
0.00 0.00 Plane5 X-draft
0.00 0.00 Plane8
0.07 0.01 Sketch49
0.28 0.06 Extrude6
0.14 0.03 FIN PERIMETER Draft7
0.07 0.02 Draft15
0.28 0.06 Fillet25
0.28 0.06 Fillet26
0.07 0.02 Draft8
0.07 0.02 Fillet6
0.07 0.01 Fillet9
0.07 0.02 Fillet10
0.07 0.02 Fillet12
0.07 0.01 Fillet13
0.07 0.02 Fillet14
0.00 0.00 Plane10 Draft Neu Web
0.14 0.03 Draft23
0.21 0.05 Mirror1
6.93 1.55 Combine1
END OF FOLDER

0.91 0.20 Fillet21

START OF FOLDER "Locate Projection"
0.28 0.06 Surface-Offset4
0.07 0.02 Surface-Offset6
0.07 0.01 Surface-Offset7
1.33 0.30 Surface-Untrim1
0.00 0.00 Surface-Offset8
3.99 0.89 Surface-Trim17
3.08 0.69 Surface-Trim18
0.07 0.02 Thicken4
0.00 0.00 Surface-Offset12
0.07 0.02 Surface-Offset9
0.35 0.08 Surface-Offset10
0.00 0.00 Sketch50
1.33 0.30 Surface-Trim19
3.29 0.73 Surface-Trim20
0.00 0.00 Surface-Offset13
0.07 0.02 Surface-Offset14
0.14 0.03 Surface-Untrim2
2.73 0.61 Surface-Trim21
3.01 0.67 Surface-Trim22
0.98 0.22 Thicken5
0.49 0.11 Draft17
2.38 0.53 Shell2
3.29 0.73 Combine3
0.49 0.11 Fillet27
0.91 0.20 Fillet28
END OF FOLDER

0.00 0.00 Body-Delete3 FINAL CLEANUP

 

I just posted the copied list of feature regeneration times for a part
I am making. I would like to post a picture, but I can't at this time
due to NDA.

Notice that offsets and delete bodies don't make much of a ripple.
Combines and Delete Faces take time. Makes sense, as they are more
"topologically challenging", making the computer think more about how
new faces are going to be trimmed.

 

Ok, between this and Ed's comment's, that's useful information. I'll
try to get some time to test on one of my models if removing surfaces
improves things. If it's a wash, all things considered, I'd rather
have them available, and we can just chalk it up to different ways of
doing things.

Actually, it would be interesting to see if your regen times actually
get slower if you suppress all of the Delete Body features. Are these
bodies all surface bodies or are some of them solids? I aree that
deleting extra solid bodies is a benefit, but I think the jury's still
out on surfaces.

matt