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sadkkf
10-17-2011, 03:55 PM
Okay...in another thread, I asked about importing CAD files, but later learned my client is using SolidWorks instead so I asked if they could send me a .stl file, but they want to give me STEP files because, he says, they only want to show the outside of the part, not the entire assembly.

I've never used these before so I have no idea what they're like/what they do. Any input?

Thanks again!

Andy Meyer
10-17-2011, 05:05 PM
first, CAD is not the name of an app, CAD means computer-aided design. SolidWorks, AutoCAD, Catia, Pro-Engineer are all CAD apps. CAD apps use their own native file formats, STEP and IGES are kind of general CAD file formats most CAD apps can import and export. CAD files are parametric objects, not polygonal meshes. CAD is one side of the 3D world.

the other side of the 3D world is CGI (Computer Generated Imagery) with apps like LW, Maya, XSI, Max, C4D... most of them use polygonal meshes. while CAD and CGI both use 3dimensional objects, they are completely different. thats why the data exchange between the two sides of the 3D world is not that easy.

your task is now to convert CAD 3D data to CGI 3D data. STEP is the best source for the conversion from CAD to CGI. it is a common way to use a converter app like Rhino (or others like mentioned before) for that job. Rhino can read STEP files (and many others), convert the parametric objects to polygon meshes and output file formats for CGI apps. for the use with LW i suggest to output OBJ files. open the OBJ files in modeler and save as LWO files. you can also use OBJ importer plugins like mentioned before, but modeler can import OBJ without plugins too.

you will notice that the converted mesh/geometry isn't perfect. but OBJ files can store Vertex Normal Maps, these vmaps help to make the not so perfect mesh look good. the down side is that LW does not handle vmaps very well. in fact, the vmap cant be manipulated at all with LW. the vmap is stored "on" the vertices. if you rotate the mesh in modeler or change the direction of poly in some way, the vmaps data stays with the vertices but it will not update the normal information and that will screw the look of the smoothed mesh completely. you can move and size the whole mesh as one without problems. you can move and size detached parts of the mesh. or you can cut/copy detached parts ot the mesh and paste it in other layers or other lwo files. just dont do any operation that will change the angle of polys or add/remove vertices in any way!

in layout you can rotate and deform the objects, that is something else than the poly manipulation in modeler! so if your converted object does not point to the right direction, rotate it in layout, not in modeler! or make some changes in Rhino before you export as OBJ. (by the way, Rhino is much more than a 3D converter)

Dodgy
10-17-2011, 05:09 PM
I'm not sure what he's on about. We use step files and they're just another cad format. However they are smaller and faster to use than iges and sat and yet seem to have more detail (objects are split into layers by part, each layer is named after the part). I use MOI2 to do the conversion to lwo since it has a range of options for tesselating and only costs $295.

Works fairly well for me so far.

phillydee
10-17-2011, 05:55 PM
I I use MOI2 to do the conversion to lwo since it has a range of options for tesselating and only costs $295.

Works fairly well for me so far.

+1 for MOI--it's a rather small program, and it's got a great 30-day eval period that doesn't limit you with anything. For a modeler that cross-converts STEP and IGES, it's really quite a steal at 295. Just sayin'.

http://moi3d.com/

sadkkf
10-17-2011, 06:00 PM
@Andy -- thanks for the detailed reply! I understand CAD is a generic term, similar to people saying "kleenex" or "thermos", but it was clear they meant AutoCAD.

@Dodgy -- Thanks for the input, too. I see the trial version of Rhino allows only 25 saves, but that should be enough. If not, MOI2 sounds like a good idea and cheaper than PolyTrans.

calilifestyle
10-17-2011, 09:00 PM
Either Freecad or 123d import step file export stl.

sadkkf
10-18-2011, 08:40 AM
@calilifestyle -- great ideas. My only concern is with all the translating how will it affect the quality of the model?

calilifestyle
10-18-2011, 09:43 AM
It's really a pain i have to say. I know that Freecad lets you export OBJ. But i agree about switching between formats might give you some problems. I tried bring in a samtec connecter into 3d-coat then exporting it , the mesh is to dense . I guess if i retop it, but takes to much time. Some times even the STL file won't open in Lightwave or blender.

gristle
10-18-2011, 01:36 PM
@calilifestyle -- great ideas. My only concern is with all the translating how will it affect the quality of the model?

Translating from STEP to OBJ/(or other mesh format) - the quality is pretty much up to you. You'll need to control the mesh settings in the package you decide upon. I say pretty much up to you as sometimes (as with any translation between CAD systems) the import of the data may include some artifacts, dodgy surface edges etc...

daforum
10-18-2011, 01:45 PM
Babel 3D can convert STEP files. It's an online service...I am not connected to the company by the way, so this isn't me promoting them just suggesting a way to convert the file(s)

Have a look.
https://www.babel3d.com/Converters

sadkkf
10-18-2011, 05:35 PM
Thanks everyone!

I'm looking forward to getting the file (finally) from the client to try this. So far it's been...email, wait a day or two, then get another question, wait a day or two.... Very slow.

calilifestyle
10-18-2011, 10:52 PM
So here is an assembly image from 123d which i exported STL, then brought it into freecad and exported OBJ. I added two images, One standard render and one with smoothing at 75%. It came out pretty good. But the mats. got dropped, when exported from 123d STL.

Oh don't me wrong freecad can open iges and step files, i just wanted to see how the stl file would look.

Andy Meyer
10-19-2011, 02:34 AM
if i'm not wrong then STL ist triangles only.
so the quality of the mesh depends on the app that makes the STL.
if your client gives you STL that is not the best thing, you can not tweak coz it is already tesselated.

Dodgy
10-19-2011, 05:59 AM
Yeah, definitely look around for something that allows you to load cad data (IGES, SAT or STP are fairly standard cad formats) and export meshes, as the cad guy probably won't know what he's doing and will send you bolts with 3 million polys in them or something (I'm currently going through a lot of our old poly assets and replacing them with moi exported optimized meshes)

prometheus
10-19-2011, 10:52 AM
Probably not what you need..but anyway.

Our workflow is to export sldasm files and open in deep exploration, convert it to obj format with vertex normal smoothing and then render in lightwave, with perspective camera wich renders vertex smoothing correctly.

image.. attached lightwave render

http://www.gymleco.se/Eng/Produkter/51.php

Michael

calilifestyle
10-19-2011, 11:39 AM
Hey Prometheus ihow much is deep exploration. when ever i click on the buy now it says no and to go back. i remember it was very expensive back in the days.

Andy Meyer
10-19-2011, 12:11 PM
hi prometheus
i'm wondering if deep exploration is doing better job than rhino when it comes to tesselation? my main problem is that the polymesh always has detached polys at round corners and so on. vmaps dont cure light leaking with GI. can deep exploration make watertight meshes?

gristle
10-19-2011, 12:41 PM
hi prometheus
i'm wondering if deep exploration is doing better job than rhino when it comes to tesselation? my main problem is that the polymesh always has detached polys at round corners and so on. vmaps dont cure light leaking with GI. can deep exploration make watertight meshes?

Are the surfaces all joined in Rhino before export? If you are importing IGES data then they will need to be joined before export. I had this issue once as well, this is the cause. You can check for open edges with the edge tool.

Ztreem
10-19-2011, 03:49 PM
hi prometheus
i'm wondering if deep exploration is doing better job than rhino when it comes to tesselation? my main problem is that the polymesh always has detached polys at round corners and so on. vmaps dont cure light leaking with GI. can deep exploration make watertight meshes?

In Rhino you can set the tesselation of every surface induvidual and get as many polygons you need for not getting light leaks. You should also check that the surfaces are joined. If you download Rhino 5 beta you can also choose welded vertex normals in the export panel, this should make the model watertight.

Andy Meyer
10-19-2011, 07:43 PM
i will have a closer look at rhino next time i use it.
i just loaded the step/iges, exploded the object and exported the parts as obj.
thanks for the advice!

lansd
10-27-2013, 09:16 AM
Okay...in another thread, I asked about importing CAD files, but later learned my client is using SolidWorks instead so I asked if they could send me a .stl file, but they want to give me STEP files because, he says, they only want to show the outside of the part, not the entire assembly.

I know this is an old forum posting but it is full of common misconceptions which I have tried to stamp out over the decades. As the main CAD conversion expert, I've provided the defacto and only native CAD -> LightWave conversion system for exactly 20 years this month. Forums people most often trade incorrect answers around the world.

1) First, STL is the worst file format on this planet. No one would ever logically use it. There is next to no data in it and you've lost all the topology info, the naming, the accurate vertex normals and the object segmentation. STL files are just one clump of triangles.

2) STEP files do not provide "just the outer surface". That never occurs with any 3D file format.

3) SolidWorks comprises of almost every customer request since 1996, along with ProE, as those two programs dominate the market. There are only two logical and technically proper ways to do a 1:1 conversion from CAD into LightWave. For SolidWorks, that would either be via a native SolidWorks assembly or via a "IGES BREP Manifold Solids" file.

I respect that you may be looking for a free solution whereas all of my customers are mid-level and high-level production people. I'll refer you to this info which explains the proper way to convert CAD data for LightWave usage:

http://www.okino.com/proe.htm
http://www.okino.com/solutions/solidworks.htm
http://www.okino.com/conv/exp_lw.htm

prometheus
10-27-2013, 10:15 AM
I know this is an old forum posting but it is full of common misconceptions which I have tried to stamp out over the decades. As the main CAD conversion expert, I've provided the defacto and only native CAD -> LightWave conversion system for exactly 20 years this month. Forums people most often trade incorrect answers around the world.

1) First, STL is the worst file format on this planet. No one would ever logically use it. There is next to no data in it and you've lost all the topology info, the naming, the accurate vertex normals and the object segmentation. STL files are just one clump of triangles.

2) STEP files do not provide "just the outer surface". That never occurs with any 3D file format.

3) SolidWorks comprises of almost every customer request since 1996, along with ProE, as those two programs dominate the market. There are only two logical and technically proper ways to do a 1:1 conversion from CAD into LightWave. For SolidWorks, that would either be via a native SolidWorks assembly or via a "IGES BREP Manifold Solids" file.

I respect that you may be looking for a free solution whereas all of my customers are mid-level and high-level production people. I'll refer you to this info which explains the proper way to convert CAD data for LightWave usage:

http://www.okino.com/proe.htm
http://www.okino.com/solutions/solidworks.htm
http://www.okino.com/conv/exp_lw.htm

Uhhmm..not sure exactly what you are trying to say?
I used deep exploration for the solidworks conversions sldasm and also sldprt files to lightwave obj format, and did final renders of gym machines which I provided info about before.
I tried polytrans..but results were in fact horrible when dealing with such high level of detail with every bolt and nut in there, the UI was horrible and things didnīt export out correct.
Deep exploration was great, I could go in and manipulate items, change all surfaces as I saw fit, merge thousands of duplicate surfaces when needed, since lightwave would freeze with that many surfaces.
I just needed to rescale it with a factor of 0.001 and when exported to obj format, it became all right scale.
Vertex normal worked too after some fiddling, and rendering with perspective camera is a must to use the vertex normals properly.

Step,stl and iges format wasnīt usable, stl is a tool usable for 3d printing, so I donīt know why you say no one would use it?

I would however recommend trying modo which loads sldasm,prt files nativly, but for a good clean up, you might need the very expensive cad loaders plugin which tesselate the files to nice quads in modo.
I tested demo version of modo and loaded sldasm files, found that rotations were off,and had to employ a free script to fix it, then it was correct.
but that was quite some time ago, I think it must be better now.

Edit..I noticed...you are of course biased working for okino? but as I mentioned, deep exploration was a huge difference and superior compared to what I experienced when trying out okino and polytrans, another
matter is of course your pricing which are superior.
Michael

gristle
10-27-2013, 01:02 PM
I think when SADKKF mentioned the client wants to send STEP because they only want to reveal the outside, they mean STEP or some other dumb export, which makes sense; they dont want to hand over the native format with the feature tree. I'm pretty sure saving assembly as part in SW offers the option to capture exterior surfaces only.

I disagree about IGES being the only way to do a decent conversion. I mesh models in Rhino and you have options... Parasolid, STEP, iges..... sometimes one works better than the other depending on the originating CAD package.

Dodgy
10-27-2013, 09:03 PM
I work with Solid Edge designers and I've tried STEP, IGES and SAT, and find STEP to be the best translated into an .lwo through MOI. It's usually much smaller than the other two formats, all the pieces come in properly named layers (all the screws in one layer, the bolts in another etc) and you get UVs and vertex normals from it, although I usually dump those to reduce the final .lwo size. All three should be functionally equivalent though in terms of the curves, surfaces etc, but you might find problems depending on your geometry. I picked up ViaCAD recently for $99 which can import STEP/IGES/SAT and export as .obj, so I'm going to try that out and see how it does, as well as learning to model in it for more technical jobs as it seems to be a fully featured solid modeler and has a modelling history, snapping etc.

prometheus
10-27-2013, 09:14 PM
I work with Solid Edge designers and I've tried STEP, IGES and SAT, and find STEP to be the best translated into an .lwo through MOI. It's usually much smaller than the other two formats, all the pieces come in properly named layers (all the screws in one layer, the bolts in another etc) and you get UVs and vertex normals from it, although I usually dump those to reduce the final .lwo size. All three should be functionally equivalent though in terms of the curves, surfaces etc, but you might find problems depending on your geometry. I picked up ViaCAD recently for $99 which can import STEP/IGES/SAT and export as .obj, so I'm going to try that out and see how it does, as well as learning to model in it for more technical jobs as it seems to be a fully featured solid modeler and has a modelling history, snapping etc.

Please do get back and post feedback on viacad and how export to lightwave works.
About MOI, itīs a cool little program...I tried that out to with the demo versions, worked for simpler stuff, but not for such large sldasm files,iges files I worked with at that moment,it couldnīt handle the
high poly amount or the large iges files.

Michael

daforum
10-28-2013, 04:02 AM
Does Sketchup load STEP files?

prometheus
10-28-2013, 09:38 AM
Does Sketchup load STEP files?

Nope..unless thereīs a plugin somewhere I donīt know about.

Houdini apprentice does load iges,stl ..but I donīt see any step file.


Michael

lansd
10-28-2013, 06:02 PM
Does Sketchup load STEP files?

Well, I and the original SketchUp developer wrote the main CAD -> SketchUp conversion system in 2005. It remains the one & only native CAD -> SketchUp conversion system available. It will always do a proper job, so you need not use a free or simple plug-in.

http://www.okino.com/conv/exp_sketchup.htm

prometheus
10-28-2013, 06:11 PM
Well, I and the original SketchUp developer wrote the main CAD -> SketchUp conversion system in 2005. It remains the one & only native CAD -> SketchUp conversion system available. It will always do a proper job, so you need not use a free or simple plug-in.

http://www.okino.com/conv/exp_sketchup.htm

I Dont get it?
Do you guys have a free plugin for sketchup that converts, or do we have to buy the exporter or the polytrans,nugraf software for it to work?
Sketchup nativly doesnīt import step files as I know of.

The question as always, is there a free method of converting step files to obj or lwo, or isnīt there?...In any case we need to know more directly..the rest is up to whom ever wants it
wether or not it can be afforded.

Michael

lansd
10-28-2013, 06:18 PM
> I used deep exploration for the solidworks conversions sldasm and also sldprt files to lightwave obj format

Unfortunately the recession took them out of the picture...

> I tried polytrans..but results were in fact horrible when dealing with such high level of detail with every bolt and nut in there

This just shows a lack of understanding and knowledge. I only sell to engineering, aerospace and military companies for which I teach them the "proper" ways of doing data translation. SolidWorks to LightWave will and always has been a 100% correct conversion, always I do expect those on forums to say otherwise (since 1994 to today, so nothing has changed). (1) LightWave will due after 10k objects so you need to do a proper "Parts & Hierarchy Optimization" which is the core aspect of all my CAD conversions, and originally written purely for LightWave's deficiencies, (2) small parts removal, hidden parts removal, etc. are all part of the software and far more superior to RH's deprecated software in all regards, (3) duplicate materials do not exist because that is handled during import processing, (4) for all the people I hear of "fiddling and fixing up models after conversion", that's not something which ever occurs with mine since the conversions are correct (how else would it work??). Since my work and primary studies is in UI design and HCI, I made the UI entirely for non-graphics people (ie. engineers only).


> Step,stl and iges format wasnīt usable, stl is a tool usable for 3d printing

This is another vastly common problem with forums. It's the blind leading the blind, as a comment I make every hour. The only non-native conversions which would make any sense out of SolidWorks is #1 - IGES BREP solids and #2 STEP AP214. I have 30k enterprise companies using my SolidWorks conversion system and 50% use native SolidWorks files and 50% using IGES BREP Manifold solids. The mistake that every single person makes (who is not my customers) is that they use the deprecated, 1995-era IGES format out of SolidWorks. All high-end MCAD programs output old-style IGES by default and then people on forums complain up and down how IGES does not work - duh! It all comes down to proper education, understanding and sourcing of files. No one on earth, except those on forums who trade incorrect information and look for free solutions, would ever use STL. It's the difference between driving a LADA and a racing car. Nothing at all is worse than STL. So, use whatever you wish. But again, anyone saying that STL produces a better conversion than IGES or STEP out of SolidWorks and into LightWave simply does not know what they are saying at all.

> I would however recommend trying modo which loads sldasm,prt files nativly

That is a valid option. They would be pulling out the Parasolid data from within the SolidWorks files.

> you are of course biased working for okino?

I am not biased. I am repeating what I mention in every email I write. SolidWorks is 99% of my bi-hourly sales since 1996, along with ProE, so I cannot have people make comments on forums which have little truth to them. What you are mentioning has little bearing on the people I sell to.

> but as I mentioned, deep exploration was a huge difference and superior compared to what I experienced

They never wrote a "conversion product". It was targeted towards $100k/customer military end-users for server based file viewing. Unfortunately a fair number of people do not know how to adequately compare apples and oranges, and that is very well understood by me. For each customer, I take this into account and put them through a good pre-sales education, where I dispel their common misconceptions such as using STL, using old-style IGES, forcing too many nodes into LightWave, and in general doing a conversion process incorrectly.

lansd
10-28-2013, 06:23 PM
Well, I and the original SketchUp developer wrote the main CAD -> SketchUp conversion system in 2005. It remains the one & only native CAD -> SketchUp conversion system available. It will always do a proper job, so you need not use a free or simple plug-in.[/url]

I stopped officially posting to the Newtek forum in 1998 because most people were looking for free conversion solutions, and hence I broke my rule to make this posting today... So, you won't find a high quality CAD -> SketchUp conversion system for free and you also need to keep in mind that SketchUp has a number of key problems when importing CAD data. If you read my entire page above you'll learn a lot about converting CAD into SketchUp and what you need to consider when doing such processes. We highly subsidize our software, with most of the cost paid by our main OEM sales + our national government subsidies, but it is still not free. So, please do excuse this posting since I know most Newtek forum people only want free solutions.

prometheus
10-28-2013, 06:42 PM
lansd, please forgive me, but as I mentioned...If I couldnīt deal with polytrans and itīs horrible UI interface and navigation "compared to deep exploration" I wouldnīt call it lack of knowledge, more a lack of providing a good interface for users...sinceRight hemisphere obviously showed it can be done.

polytrans couldnīt cope with the huge datafiles in a decent manner compared to how smooth it worked with deep exploration,(tested same machines and files in both software)
I felt I had full control over everything in deep exploration, could remove parts, hidden parts, put intersection planes to cut
thru the models, choose from a wide range of display modes like transparent view to see hidden parts etc, export out with vertex normals in a proper way, and scaling was no issue, I could write out pdf doc including machine drawings for others to analyze
without having a 3d software.

I am a fast learner and learn software quite fast, so deep exploration was a no brainer, polytrans..I didnīt like, and if I were to take weekly courses for a conversion software..then no way.
As I mentioned, I donīt work there anymore, but our constructor passed the solidworks constructions of gym machines to me and we converted it through deep exploration, worked very well...that was from sldasm or sldprt, to deep exploration and using the export to obj format with vertex normals intact.
the only issue could be having to many vertex normal maps since that could slow lightwave down.

Im not working for right hemisphere and their software deep exploration..you are doing sales for polytrans, I would call that a little biased.
Im sure polytrans is great for many others perhaps and has a very important part in cad to poly conversions, but I feel the need to give my point of views on how I felt about polytrans compared to deep exploration, polytrans UI compared to deep exploration
is bad, and also what I experienced regarding handling larger sldasm files, and slowness in model navigation.

Stl and iges..isnīt what I argue about here, moi or polytrans might work nicely...but otherwise if you need solidworks sldasm,sldprt to lightwave...I would go deep exploration if the company affords it.
Now...I heard something about hemisphere being bought up...or deep exploration, so I do not know the status of it now.
I do not know whatīs the fuzz about "never wrote a conversion product" who cares..it does conversions nicely...even though it didnīt started out as such dedicated tool, and you are quoting me on this...
"but as I mentioned, deep exploration was a huge difference and superior compared to what I experienced " donīt know why you bring that up about not being a conversion product.

Edit...I have to give okino ad polytrans the credit and advantage of better pricing though.

So ..I worked on a daily basis with converting solidworks files to lightwave files, and finally rendering of gym machines in lightwave from 2009-2012



Michael

prometheus
10-28-2013, 06:57 PM
I stopped officially posting to the Newtek forum in 1998 because most people were looking for free conversion solutions, and hence I broke my rule to make this posting today... So, you won't find a high quality CAD -> SketchUp conversion system for free and you also need to keep in mind that SketchUp has a number of key problems when importing CAD data. If you read my entire page above you'll learn a lot about converting CAD into SketchUp and what you need to consider when doing such processes. We highly subsidize our software, with most of the cost paid by our main OEM sales + our national government subsidies, but it is still not free. So, please do excuse this posting since I know most Newtek forum people only want free solutions.


I think someone here actually just mentioned sketchup to use if it could import step and export out, as a free tool, I donīt think that question was brought up regarding actually work with sketchup and step files, could be wrong..but I donīt think so.
And yes..we all go for free, as our main priority..if not, well the purse comes up, nothing wrong with that.:)
We tried that with chronosculpt and nevron motion, but they wouldnīt listen ..oddly:)

moi is interesting too, nice interface, there are one demo valid for a few days which you can test import step and export to lightwave, but it will expire, then thereīs another demo which doesnīt expire, but it is limited so you cant save files.
http://moi3d.com/download.htm
117880



Michael