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Some surfaces behaviour makes me confused

muadib3d said:
Is it widely based on external references? Do you divide the geometry on different models each one for another scope - one for outer geom, one for inner, another for cores?


......


So, I imagine that it also could be with such a model as yours, when there is a need to simplify geom for calculations. But I doubt You run FEM, rather plastic anlaysis(PartAdvisor?). I am also curious how You avoid problems with merge and normals, which change the dir for quilt if You change the sequence or surf in merge inside.
Click to expand...


our master model is not allowed to have ANY external references.. our master model consists of one part, this is what we supply to our clients most of the time, Their engineering teams then copy quilt geometry out into thier parts, (so say thier first 4 features would be an outer quilt copy , an inner quilt copy (which we have to build to be offsetable so they can define the wall thicknessif necessary) and side surfaces followed by mereges and solidify. We spend a lot of time at an early stage in dicsussions with the client engineers to ensure what we provide is exactly what they need. over the years we have built up a great relationship and work pretty well with them!


We actually do quite a bit of FEA on our parts, ever wonder why it is when a 200lb father steps on his childs Xbox controler it doesn't break? it can take a bit of time to prepare teh model but not as long as you'd think!


And as for merges and surface models? well, it's all down to care and attention!


James
 
so You also do that - Xbox controler? Hats off - you are closer to enterteiment that I would dream to:))))

so how you analise Your models, in Pro\M? If so, it should be - in my opinion - hard to do that while GEM in Pro\M often fails while creating mesh for complicated surf. Or you do that in another application, like Nastran, when You prepare or heal geom directly in it?

What I would like to have, is spare time to go back and dig once again the researches for drafts and rounds as external models. I was impresive with Delphi Horizontal approach

http://www.machinedesign.com/asp/viewSelectedArticle.asp?str ArticleId=56512&strSite=MDSite&catId=2

but, it creates to much feats to take it seriously in all models. My enhancement to that was to find a way for rounds and drafts in "BIG" models. To sculp all unneeded feats in FEM calcs.

just two euro cents about way of modeling. It could be diplom made on it:))))
 
sh*t, when(if) I reached so high surfs quality?
smiley5.gif


it looks amazing
I gonna be honest James - in my previous job I did not pay attention to surfs and their quality so much. Indeed, it was no so demanded. Now, When I tried it a little, well, I have some respect for such a guys which do models like this one.

if a simple mouse takes 50h to bring it to Pro\E by scanning, how lond did it take with this controler?
 
nice, how then it takes to finish model in Pro\e?

with my back body for LCD TV 46", it was about 2 weeks to build main geom, that stayed till this moment, then it took another 3 months to add a lot of small details, and a little changes which tended to appear in less desired moment. What I am still happy with is decision to put rounds and drafts as late as possible. This decision is still paying back, I can deal with geom as I want, no problems with relations to rounds, drafts. At begining regneration time took 20 seconds, now with solids and all feats - few minutes.
 
I'm not too sure on the timing to completion, it depends on how the ID develops during the process also... one of our strongest advantages is that we get in to ProE earlier which allows our Clients to get started earlier, as the ID develops, we can update the master file and our clients parts update also! obviously there are some failures but there are reles where can be put in place to minimise these..
 
ok, back to to surfaces

I wanted to make surf by boundary with curvature but it failed(tangent with no problem)

View attachment 3913

I investigated the case and found the the reason could be the curvature plot of intersection curve which is used to do this surf

View attachment 3914


the base is sketched curve which entities were changed to spline

View attachment 3915

there is a peek in curvature, I thought it comes from spline points, so by modifing spline I could remove it

View attachment 3916

but till normal entities in backround exists, I can not modify the spline, I had to delete them,

View attachment 3917

then, I deleted unnecessary points and I achieved what I wanted

View attachment 3918

the question is:

Is there a tool to distribute points on spline in sketcher? To not make it manualy? Second is it possible to manipiulate spline with entities in backround to still have dims to play with?

How You(all) would solve this problem?
 
just to complain a little on Pro\E and its feature relationship
smiley19.gif


Well, if somebody pay attention to this topic from start, he\she knows it is all about TV back body I am dealing with. Generaly it is almost finished. But, as iti is in life, some big changes waits in dark to occur in the last, not expected - desired moment
smiley7.gif


This time was the same. Some important changes has to be done, and it is not problem for me to do that. However, such moments like this tend to bare the software weakness.
smiley18.gif


I had to delete some features I had done with surfaces. Problem is that Pro\e does not show all relationship in Parent\Child window, if another features are done on top of it as solids. See below pics as example.

View attachment 4092

One can see that after attempt to delete it appears that in fact some other features are depended. sh*t, why is it not shown in Parent\Child relationship?
smiley7.gif
 
ok, back to the subject again

well it was quite long break since my last post here, but LCD 46" Project sped up in the last two months, focusing my all attention on some boring but important tiny things - right drafts, rounds, many tiny changes that required much more effort than expected.

Anyway, in the last week I`ve had an oppurtunity to to take a little break of this, so I came back to surfacing topic.

Below You can thing what I was dealing with

View attachment 4358
ok, it is not a model from Pro\e, it was done in Photoshop this is design work that comes from a guy named skinny, deatils below

http://www.coroflot.com/public/individual_file.asp?from_url= true&sort_by=1&portfolio_id=80167&individual_id= 3135

It was enough easy and simple, but still intresting and challenging to face it with Pro\E.

So this is what I have done with Pro\e

View attachment 4359


View attachment 4360
 
and now ....

1)feel free to judge, discuss this model, I am very open for any words of criticism. I can face them. Since it is not, and it wasn`t aimed to be 100% accurate, I am curious of Your approach to model this part

I used following curves

View attachment 4361

Since whole part seems to be easy to make it contains some trouble surface transitions, which I had many problems with

2)here, I could not avoid 3 side boundary - any suggestions?

View attachment 4362

3)rest part of this patch I made in following way

View attachment 4363

any idea for work around of these two surfaces?

Finaly I am very curious of your tips for this model.
 
something more - does anybody know right\correct\easy\any way of editing curves through points?
smiley5.gif


gush - how horrible it is! I`ve faced this many times. I have a curve, it is used by some boundary blends, then, late in modeling process I need to edit it, to push this curve through new points, and sh*t, it does not work.
smiley11.gif


The pop menu in curve through points is just p.i.a!
smiley7.gif


I pick delete points option, to remove existing ones, and then add point to pick new, but no, no way man! Aaaargh... I wish I have ISDX
smiley19.gif


any idea?
 
Curve through points huh...

Here are a few tips. If you want to move a point on the curve to another reference, then reroute the point. Be careful with the tangency condition(if any) because if the new condition is a surface and the old one is an edge, it wont accept it. You have to edit the curve and clear the tangency. If you have tweaked the curve, chances are that the tweak could be all over the place after you rereference. To delete the tweak, edit the curve, then click define curve points, and do nothing. Click accept and the tweak should have disappeared. ANother annoying thing about curves are if they fail and it is a tangency problem, you cannot click tangency to clear. Instead, click define points as per the last trick.
 
thx gristle

You`re right with clear tangency constraint first to set up new points after. I figured this out in the weekend, however it did not change my statement considering curves through points at all. It just sucks

Thx for further info - specialy Tweek option. I assume PTC left this function(curves through points), and it is not going to change this, to push poeple to buy ISDX. Nice and clever, approach considering marketing side. Not nice and justice considering users.

The same with splines in sketcher - you can not join them having the same curvature plot in the joint. There is not contstraint for this. I read a trick to work around this in

http://www.synthx.com/tom/sy_tip_0303.htm

but this has limited use

without IsDX I am pushed to use curve through points instead creating spline in sketcher to have this smooth curvature transition between splines. Not a pleasure at all
 
Hi.

Yeah, curve through point is pretty nasty to say the least. I am stuck using it for the same reasons as you. There is no excuse really for not keeping up development, even if they streamline the panel, like they did with Swept Blend in WF3.

If we had more control over spline control points/vertices in sketcher, then we could set up C2 connections ourselves, as you would in rhino. I cannot see this happening though.
 
The lack of this funcionality is really sh*ty. The sketcher should has this, there is no excuse for this at all.

I am trying to face common surfacing tools before I move towards ISDX. I see ISDX more powerfull. That is obvious statement, I know, however the advantages seem to be clearer now, after attempt of using simple surfacing options.

There is good sentence describing my way - "You have to face the hell first, to know what really the heaven is"

The same with Pro\e
 
The most useful (only?)way to change which points are used is to reroute. this point was already made in this thread i think (gristle).
Edited by: jbuckl
 
this time simple question

I struggle now with model for simple lever.

These are my main curves:

View attachment 4417

I do not know still how to bite it. First I created bottom surface - and then the second one. But it could be seen while previewing this dynamiclay it won`t fit together

View attachment 4418

so then I thought about creating new curve and new boundary blend

View attachment 4419

but this set contains hidden tangency between two curves.

Do You guys have any work around for this case?
 
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