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Some surfaces behaviour makes me confused

Jacoolo

Jacoolo

New member
Hi all



So long with Pro\E and still this software can give me some questions without
answer



So, what happened?



I usually deal with solid to create geometry. And as far as I remmember it was
no such reason to push me to use surfaces through whole model creation. I used
it rarely for some complicate cores or cavities, but that was all, till these
days.



So, I am heading the project to create housing(plastic) for new LCD TV, and I
thought - ok, it will nice to make it surafces than solids!



But, some surface behaviour drive me crazy - lets deep in details



I wanted to make a pocket for screw and than pattern it, like in pic below

View attachment 3257

View attachment 3258

but it happens that I can not pattern merged quilts. So I did first a Pattern for pocket quilt and then make a merge for each of them

View attachment 3259
View attachment 3260

View attachment 3261

so everything is ok, but I have a bad taste after that for surfaces - making the merge for each pattern instance is time consuming. In solids you could just use ref pattern and that is all.



Now I want to make a round for those pockets and something tell me that I would not be able to make by pattern, rather in the same was as for merge, am I right?

In addition I have to do this also on second side of housing.

is this all correct or there is another way to this with less work?

muadib3d
 
You can reference pattern the merge and round.


You can group features (recess extrusion, merge, round)
and pattern.


You can copy the sufaces of the first topological feature
(the completed pocket) and pattern ...


Some caveats may apply to your specific situation.
 
first - I did it

but let me tell You how it happened

I made a group of features including merge

View attachment 3263

and after that I made Copy, Paste > move

View attachment 3264
no result

so I created first the group without merge, pattern it, then merge for first quilt and ref pattern - still no result

so I redfined the merge and I do not know way I click Swap button

I did a pattern again and then it worked

so in two first ways - no result

with swap nad ref pattern - yes

so finally what is this swap

and why it does not work when the merge is in group only as second pattern?
 
Ah, yes! Merge Pick Order.
The logic is a little complicated and I'm not sure I
understand it that well, let alone well enough to explain.


As a simplified explanation ...
_ Create a couple of surface features and merge them.
_ Now try to Hide the quilt.
_ You'll find that Hiding the first picked feature
works, the second won't.


So, it's sort of a parent / child relationship; the
first picked object becomes the parent, the quilt 'head'.
This is probably important for Patterned Merge features
in a couple of ways ...
_ You want each successive quilt to merge a 'copy' with
the 'main' quilt rather than trying to merge the copy
with it's original (which can't be done).
_ Merging may change the surface Normal direction of the
second picked (?) object. The 'keep' side of the quilts
in an Intersect Merge is determined by the surface Normal
direction (?). Beyond my analytical capabilities, but
there might be some problem potential if the 'main' quilt
has its normal flipped as a result of a patterned merge
instance.


(I don't KNOW any of this stuff. Just guessing, trying to
make some 'monkey with football' sense of it.)


There may be a bug involved. Take a look at this ...
[url]http://www.mcadcentral.com/proe/forum/forum_posts.asp?TID=26 213[/url]
and the referenced tutorial ...
"Faster Identical Patterns with Surface"
http://www.ptc.com/go/wildfire/learn/tutorial_452/index.htm
which may touch on something useful for your endeavor.


Good luck with that. It's going to be a learning experience. I'm
always a little torn by the; "Do I want to do this as solids, surfs
or a mixture of the two?", question when modeling certain objects.
It ~is possible~ to copy solid surfs and completely 'wipe out' a
solid body (Solidify -> Cut) if necessary. Pretty extreme, but nice
to know I guess. I sorta wish Pro/E had an UnSolidify command,
though in reality, it's not that difficult integrating solid and
surf features. It may, occasionally, take an extra step to cut away
some complicated solid topology before successfully merging surface
features with the solid body.
 
thanks jeff

unfortunately I have again the same problems with merge yesterday on the second side

this link You senf is for patterning in solid geom

so for the left side all works after swap, but on the other side it is not workin even with swap

I made some investigations and this is what i found I take it as a cause of problem:

*this is the merge settings for the left side where pattern is possible

View attachment 3266

and this is the setting of merge for the right side. No matter how I swap the surfaces there is no result with patterns. In addition I noticed that I can obtain the same settings - positions of arrows and sequence - as in the merge on the left side

View attachment 3267

finally I had to make pattern for quilts and then make 4 merges by myself

and this is the finish of this story - not lucky one unfortunately;)
 
but why u making this with merging quilt muadib?? if u r doing a job that is actually easier then ur way, soin this case the question is wrong itself. just make this whole solid, even after creating the outer most surfaces, close themwithany surface and make them solid, then make features like that pocket and pattern. after that u can easily shell it.


anyway, there is another way, just make acopy of this feature first by copy >> paste special then u canpattern the transofrmed copy easily.
 
My 2 cents


Surfaces should only be regarded as "construction" features in a similar manner to datum-planes, curves etc.


You always want to end up with soild features at the end of the day.


Typically I start to use surfaces for 2 reasons:


1) "Copy" surface.


2) Boundary blends.


Master these plus "surface merging" and you'll be a master.


btw I wouldn't have touched surfacing with a 10 foot pole in this case ....
 
> not lucky one unfortunately


Yes, I see. Mirrored quilts (in conjuction with Directional Patterns?)
give it fits. If there is a 'logical' reason for the failures it's
beyond my comprehension.


Going a couple of extra steps seems to help ...
_ Mirror the 'toolbody' quilt.
_ Selectboth toolbody quilts.
__ Copy.
__ Paste Special with a Move.
_ Dimension Pattern the Moved Copy.
_ Merge the original, then the mirror.
_ Merge one Moved Copy quilt and (Reference) Pattern.
_ Merge the other Moved Copy quilt and Pattern.


2007-03-16_110301_mirror-pattern-merge-wf2.prt.zip



- - - After a little more looking - - -


I think I understand a little more of the failure (and think it's a bug).
The fix is relatively easy. When the Merge (mirrored quilt) Pattern fails
and you get thrown into Resolve mode; Quick Fix -> Reroute and pick the
2nd mirrored quilt instance. The Pattern will solve and seems to be stable.
The attachment has three simple examples / variations, all fixed the same way.



2007-03-17_020137_3_files-wf2.zip



Edited by: jeff4136
 
thanks jeff

I will try that

I know solids well, and spent a lot of time dealing with them.

Usually there were so many projects to finish that it always was lack of time to dig some new stuff in Pro\E

so, it occured that with this new project I have to disposal much more time to play so I choose surfaces

Well, what I can say - solids are more comfortable to deal with, surfaces seems to be more demanding.

Still, I want to give surfaces one more chance and find out all what is neccesary to give clear opinion.
 
hello jeff


I took a look on your models and one that I love the most is that with offset features.

I supposed that offset is only available for solids - my fault. It seems that this feature give me "almost" all what I want with less features count.

I write "almost" becasue the offset have no otpion to flip draft angle. In my pocket I know exactly the bottom of pocket - there is a screw and there should be place for a head. So the top surface is not important and is made by draft angle.

However with offset I have to choose first top surface and then I have to make sketch that after draft give me the original dims. So It is work around - maybe not so good as a drawing and dimension style but it works good in Pro\e and it is faster than merges.

thx again jeff

p.s btw - the quilts seuence in merge is critical for pattern - I swaped quilts and the pattern in your model failed.
 
Best way to do this is this:


Only concentrate on one of the lugs. Add all the rounds, cuts, features and all geometry needed to create it. Then, copy the surfaces using seed and boundary, translate a distance of '0' and then pattern the translation. You can then solidify the first feature and pattern the solidification. I have always found this to be the most stable mathod of patterning complex multi-featured geometry.


Phil
 
hi all

back to the thema with two cents

first - i am far away with whole design since then, but some thoughts could not let me sleep till they be written

so surfaces - "oh my surfaces how strange you are..."

first, if someone still remmeber the key problem from the beginning of topic - I wanted to make pockets in surfs and then pattern them - finaly, I did it but it was pain in ... rather then piece of cake;)

so, I was searching another function and I thought about Offset which looked like very intresting, till... better take a look on pics

View attachment 3446

this is cool, but...

View attachment 3447

here the problems appears, offset check when sketch cross the end of surf and ends exactly there, I was counting for a little more fucionality

second thing about surfs - what drives me really crazy is the importance of right sequence in surf modelling. Till You have no merges, no problem, but since them, You have to take care what with what, because if You put something new by Insert mode, the normal of surf can change and all further merges go to hell

so, finally, if You do not want to pay attention on what exactly normals are, place all changes always in the end of tree, sad, but it is like that.

in this case, solids are better

and this in the end
 
today another strange behaviour of surfs

I wanted to make an extrude with one side as "blind" and second as "up to selected"

firs I copied interested me surfs to make them as quilt and then extrude but it failed

View attachment 3566

then I make the same extrude but till round surf as it is seen below. The point is that next operation is needed because extrude does not touch sloped surf

View attachment 3567

so finaly the question is - why it works for rounded surf and not for quilt?

Are normals the problem?
 
this time no surf related but it is still the same project concerned

I noticed some behaviour of Pro\E and I do not know if it is the normal one

so I have an assembly for whole LCD TV and I made Simp Rep with substitute option for back housing(now with the almost all ready the number of drafts and rounds is crazy) with no drafts and rounds

but then, there is no way to push Pro\E to display this body by View Manager > Style option with wireframe display or any else

strange
 
Some question surfaces related:

*am I right that intersection curve can be made only from sketched curves(intersection of surfs is obvious to me)?
*is it possible to convert back entities from spline to normal ones in sketcher mode?
*is it possible to delete some of controls points in boundary blend?
 
during this challange
smiley17.gif
I met some problems I want to avoid in the future, nad in this particular model either

So know I want to introduce first of them:

View attachment 3854

I tried to merge these two surfs, and it was succesfull but the result does not make me happy

two joined surf are jagged on common edge, there are problem with thicken option
in addition they look a little concave but they should not

here are details

*curves

View attachment 3855

*first boundary

View attachment 3856

*second boundary

View attachment 3857

I tried to make second boundary surf tangent to first but it failed, because Pro\e calims that some of boundary curve are not tangent to surf, but they should

any suggestions?
 
Is it possible to check curvature of Sketche in the Sketcher Mode without converting all entities into Spline?
 
I am really p..ed off on boundary blend

Bounding curve(s) are not tangent to tangent surface at highlighted point(s).<br style="font-style: italic;">Relieve tangency conditions or redefine the curve.

*boundary conditions:
View attachment 3858

*problem
View attachment 3859

Can any one explain me what is going on? What do I do wrong? The top curve is common for first quilt and second. It is an arc. So why does Pro\E prompt this as not tangent, if it should be?

After about 40 min spent on this subject I feel I am lost in the forest.
 
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