Really need some points of direction

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 From:  thsorensen
6556.1 
Hi.
I'm still really curious about Moi,and I'm still considering to buy the full version, and so far I have seen numerous of video tutorials, and I must say, Moi really looks simple to use.

So for the last week I have tried to create a 3D model from some images I have of a old Scania truck.

I have tried in several ways and techniques to create the object, but I'm still struggling, and now I really don't know what to do.

First I tried to use lofts to create the upper part of the house(attachment 01 and 02), this was partly successful. When I tried creating the curving of the roof(03 and 04) with sweep, I really don't know what is happening...

After fiddling with building the object from up to down, in numerous ways, I tried creating it from another perspective - a kind of silhouette(attachment 05), but LOFTS didn't do anything when i tried using it(no error messages, etc).

So, finally, after working with different techniques for a week, I tried to just use a solid box(attachment 06 and 07) to just boolean -> diff out everything I didn't need. But when I tried to fillet to create some rounded corners, it just did something really strange...

Does anybody know how I should attack this situation? I really like the GUI and the simpleness of Moi, and I'm absolute willing to learn more about this tool to be able to build objects from images.

---
Thomas

01_lofts_curves:


02_lofts_partly_ok:


03_sweep_roof_curves:


04_sweep_roof_result:


05_siluett:


06_fillet_corner:


07_fillet_corner:

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 From:  DannyT (DANTAS)
6556.2 In reply to 6556.1 
Hi Thomas,

Vehicle modelling is a pretty advanced area to start off with, you should first model simpler items to get a feel what each command is capable of and their limitations there are lots of tutorials on the internet about vehicle modelling, it doesn't matter what software is used as long it's a NURB's based modelling program the technique would be the same.
Here are a few with a quick look on the internet.

http://vimeo.com/17694097
http://www.youtube.com/watch?v=5XMI6mJ2iV0
http://www.youtube.com/watch?v=yAoYVuJ7FWw

Cheers
~Danny~
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 From:  kevjon
6556.3 
I would tackle it by lofting using the techniques Samardac describes.

http://moi3d.com/forum/messages.php?webtag=MOI&msg=6058.1
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 From:  Michael Gibson
6556.4 In reply to 6556.1 
Hi Thomas, yeah I'd agree with what Danny writes above - in general vehicle modeling is one of the most advanced types of models to work with so it's not really a great initial starting point, you're going to be thrown into the most difficult types of things right off the bat.

It's probably a better idea to do a variety of more simple mechanical part type shapes first so you can gain some general familiarity with how MoI operates.

Also for specific problems it can help a lot if you would post the 3DM model file of what you're showing instead of only screenshots - a lot of problems can have to do with specific things about your particular geometry and it's difficult to analyze that from a screenshot.



> First I tried to use lofts to create the upper part of the house(attachment 01 and 02), this was partly
> successful. When I tried creating the curving of the roof(03 and 04) with sweep, I really don't know
> what is happening...

If you could post the curves you're trying to sweep, that would help to give some feedback on what's going on there, it's hard for me to tell what is going on in the screenshot there.

But probably the better way to form a closed top would be to use the "Loft to point" which is new in version 3, that's what Kevin mentions above. Also here is another demo of it:
http://moi3d.com/forum/index.php?webtag=MOI&msg=6082.10
http://moi3d.com/forum/index.php?webtag=MOI&msg=6082.8



> After fiddling with building the object from up to down, in numerous ways, I tried creating it from another
> perspective - a kind of silhouette(attachment 05), but LOFTS didn't do anything when i tried using
> it(no error messages, etc).

Again if you could post the 3DM model file with the curves that failed to loft, that would help a lot to do a proper analysis.

The best that I can say from looking at the screenshot alone instead of being able to see the actual geometry, is that it looks like you may have a duplicated curve for the middle station, that will probably mess up Loft if you are giving it curves where some are duplicated and stacked up right on top of each other.



> So, finally, after working with different techniques for a week, I tried to just use a solid box(attachment
> 06 and 07) to just boolean -> diff out everything I didn't need. But when I tried to fillet to create some
> rounded corners, it just did something really strange...

If you could post the object that you were trying to fillet, that would help me to give some better feedback. There are an awful lot of different potential things that can mess up filleting, such as trying to make fillets that don't fit within the available space and would cause the fillet to self intersect or bunch up, or to totally consume away an existing face or edge...

It looks like in one version of that pass, your side profile you drew was only made up of a polyline rather than a smooth curve, that resulted in a lot of little segmented flat pieces after doing the boolean:



That kind of segmentation with lots of pieces at shallow angles to one another is not very good for filleting, it tends to make things difficult to calculate the corner juncture areas where the different fillet pieces collide into one another.



> Does anybody know how I should attack this situation? I really like the GUI and the simpleness of Moi,
> and I'm absolute willing to learn more about this tool to be able to build objects from images.

I'd definitely say start with some simpler projects to begin with, both vehicle modeling in and also a reverse engineering process itself are advanced areas of operation and probably more something you want to work up to.

- Michael
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 From:  thsorensen
6556.5 
Thanks for your answers!

I was perhaps a little impatient at first, but now I have tried a little more with LOFT, and I am quite satisfied with the result so far.

The technique I have found works best for me, is to start from the bottom, then copy the curve layer, and then move upward along the chassis while dragging on the curve, until I reach the top.

What is challenging is when I have worked my way up the drawing, and get to a point/curve that was not created in the original bottom.
The way I work around this, is to delete all the curves, then add the missing point in the bottom curve, and then make all the curves again. It's time consuming, but then I get a nice and smooth LOFT.

The reason why I am trying to learn 3D-modelling is that I want to write out the model on my 3D printer, so all the little details that requires years of training to master, I'm hoping to learn on my way. But roughly, I'm satisfied with managing to create a shell, and then do rest of the detailing with my Dremel :)

Michael: When is version 3 out? The thread you linked to the "loft two point" looks very interesting, and I think that the technique would suit me very well! :)







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 From:  Michael Gibson
6556.6 In reply to 6556.5 
Hi Thomas, it looks like you're getting some good results with your persistence!

> Michael: When is version 3 out? The thread you linked to the "loft two point" looks
> very interesting, and I think that the technique would suit me very well! :)

It's getting pretty close, I'm in the end stages of it but I don't have a specific launch date quite yet. It might be something like 1 or 2 more months from now though, depending on how some of the final steps go.

- Michael
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