It keeps crapping out on me. I will make a totally un-related revisions to a
mold design and then whammo-a cavity feature way up the tree all of a sudden
gets a re-build error. The error message says something about inconsistent
geometry and changing the scale factor. Well for one thing-I don't use a
scale factor when I make cavities. I couls rant on, but must go back and try
and save the model that SW is trying to ruin for me.
SW05,sp0.1 on Win2K.
John, it just may be that putting in a cavity with "0" shrink is what
might cause the problem, if SWks programmers didn't consider that some
people do NOT want to use shrink in that way.
You never have been able use it because it works as an offset and not a
scale. It makes the cavity the right size, but the core is 2X the factor too
small. I guess they'll never fix it at this point.
I've been scaling parts and using "0" shrink for years, never had a problem.
I think it has more to do with some rebuild weirdness myself. 2005 rebuilds
way to much when it doesn't need to, and not at all at times when it does.
Damn! What in the heck is wrong with SolidWorks programmers if "Scale"
doesn't work right? I mean, how basic a task is that. In fact why
leave it in if it is NOT right?
I obviously do not understand what is wrong with the Cavity Feature!
This is scary.
Can you describe easily how you get a non-equal scale when using
There is more going on here than I thought. When I have checked, my
cavitie's scaled sizes came out right when I embed a model in a block
and use the cavity feature.
In my 2nd sentence "...if "Scale" doesn't work right?", I obviously
wrote too quickly and it should have been "Cavity Feature's Scaling"
doesn't work right.
Obviously the stand alone Scale feature is working right.
In some situation Cavity Feature's Scaling does NOT, but I am confused
on that part.
Thanks - Bo
I was talking about the "shrink factor" in the cavity dialog. It uses
offsets so the female cavity gets bigger (right), and male core gets smaller
(wrong). It's only half right. It's been this way forever, and is totally
usless for mold design.
What I've allways done is apply a scale to the part, and subtract the
core/cavity features usink "0" shrink factor.
Non-uniform also doesn't work right with regards to molds. It turns bosses
with circular cross sections into ellipses. We both know an ellipse isn't
going to shrink into a circle. You have to manually edit these features to
make them circular again. This was probably just a generic Parasolid
function that they simply turned on, without taking the time and effort to
make it usefull. It's also very sensitive to marginal geometry. Your model
has to be clean.
Well,,, I guess I gotta eat my words on this one, they fixed it (sorta). I
don't think I've tried it since SW99.
It still has problems though. If your subtracting the whole part from a
solid block, and then cutting away the parts, it works correctly. This ,
however, will only work for very simple parts. If you build up the core and
cavity inserts from two seperate pieces, like I do, it becomes a problem
because the "cavity with shrink" operation wants to extend the edges of the
parting line. Much easier (for me at least) to use a scaled configuration of
the part. There's alot fewer potential rebuild errors.
Another possible source of our mis-communication would be if your using
"mold tools". I don't use them. I played around with them in 2004 and 2005,
but couldn't see any benefit. Mold tools creates to much unnecessary
geometry, (surfaces), and most of what I did with them was prone to rebuild
errors. I guess they figured that most mold guys are used to working with
surfaces that way, and designed the tool based on these ASSumptions. The
truth is, I can (most times) create cores and cavities without using
surfaces at all. Sometimes reference surface for the parting line, but
that's about it. This results in a much more robust (hate that word, to
"geekish") mold assembly, that rebuilds correctly when changes are made to
the model. This is important to me because, sometimes, I'll have to design
the tool before the parts are finalized.
Mark, that bit about more stability using the cavity feature vs. surfaces is
exactly why I don't like the mold tools.
They basically now have a tool that doesn't do anything well except demo
well with a pre-selected part. I bet there are some pretty frustrated new
users who thought they were getting automatic core/cavity generation.
Yea,, It's pretty useless for real molds.
For years mold designers have been have been shouting for better "surfacing"
tools to design molds. Most of these guys were probably used to designing
molds in CAM packages like Cimatron, Mastercam, or Powershape. They
responded to the shouting litteraly, instead of taking the time to think
through a "smarter" way that took advantage of the SW environment.
You have to be carefull what you wish for I guess
getting pretty far from my original topic here, but SW has indeed improved
it's surfacing capability in areas that I regularly take advantage of.
Untrim is a fantastic tool. I also use `replace face a lot. I am starting to
use the `move face' function too. All of these little tweaky features
weren't around until recently and I appreciate having them.
It's the full-on surfaces approach to core/cavity split that I think is
being applied wrong by SW. On the other hand SplitWorks also uses a surfaces
based system and it works pretty well. It's all in the way the application
I agree. Surfacing has improved alot, and I do take advantage of it when
appropriate. I look at it as more wrenches in the ol toolbox.
As far as thier implementation, it is pretty lame. Myself, and others, have
offered to collaborate in the development of usefull mold tools. Never got a
response. I kind of get the feeling that ther person responsible has read
books, and had molds carefully described to them, but has never seen one
That has to be the second most absurd excuse I've ever seen for top posting
next to "that's where my cursor is so that's where I start typing".
Part of the blame for that though, I will lay on the bumbling halfwit who
originally combined an email and news client into a single program.
Yeah, yeah, yeah, the whole Anarchy on the Usenet thing. I'm hip to it,
So your common sense tells you to read from the bottom up? It also tells
you not to delete that which you're not responding to for the sole
purpose of wasting bandwidth and making posts hard to read? You've got
some weird common sense there, Sporky.
A: People who top post.
Q: What is the worst thing about the Usenet?
Black Dragon Joyfully killing Google Groups posts since late 2004.
So, what do you give for a reason to eschew top posting? Tradition?
That halfwit made it possible for many people who don't use Unix to
enjoy the benefits of Usenet. Of course if that halfwit and others like
them had avoided Windows in the first place we wouldn't be where we are
now . . . without both the benefits and the disadvantages.
I typically delete everything except what is relevant to my reply,
unlike most who post. That's in direct contradiction to your
accusation. But I often top post because it makes more sense to do it
Give me ONE good PRACTICAL reason, there BD. What's so horrible about
I already gave my reason. I don't know about you, but I read from left
to right and from top to bottom. Top posting forces reading from the
bottom up, which is usually a good enough reason for many people to
simply ignore such posts. And quite often I do.
What is with your fixation on Unix? It has nothing to do with top posting
or software. Usenet news and email are two different things with
different common practices and behaviors and most software that tries to
incorporate both into a single program usually does either one or the other,
or even both, rather poorly.
...do follow along now, children...
It never makes sense to do it, on Usenet. Email is an entirely different
matter. Hence one of the reasons combination news and mail clients were
not a good idea.
It should be obvious to those with some common sense.
Here, these will help, if you let them.
Black Dragon Joyfully killing Google Groups posts since late 2004.
Mark & John, I pretty much agree with you guys. My plastic parts I
design gain nothing from using sophisticated tools which are more prone
to errors or limitations of one type or another. I, too, virtually
never need to use surfaces for my types of parts.
I don't design molds any more, but I need to be able to accurately plan
layouts for all sorts of things (some indeed 'weird') with multiple
sleeves and core pins and removable inserts, water jackets, etc. and
need to be able to 'rough out' a cavity set layout before I take it to
the mold maker. I would look real foolish if my use of Cavity Scaling
for shrink were off for simple parts.
As a side note, I have watched the use of "organic" cell phone shapes
come, and, now somewhat surprisingly, receed into the background. I
suspect the manufacturing issues and costs associated with making weird
shaped cell phones weren't worth it to consumers and the manufacturers
I don't care what software package a designer uses, it is going to take
a lot more worki creating all those off-beat curvy 3D shaped mating
parts with all their little mating, assembly and locking devices.
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