CAD for 3D Printing

[TurboBoost910]

Hey all. new here and new to AutoCAD. I havent played with it for 12 years, but i have learned the basics pretty quickly, and am a pretty easy learner. I have 2014 for Mac, full version.

 

I am trying to create 3D models that will be printed using a high quality 3D printer in Ultra Frosted Detail.

 

I am knowledgeable on how to draw my shapes and extrude them to 3D, but am curious is if I need to change the shapes to "solids" for the printer to print it that way? For instance, I have a model train car that I am working on, and I have attached the file below. What I did with this basically is drew the shapes and extruded them to the thickness that I needed (Measurements are actual size and will need scaled down after the model is complete).

 

So If I need to make them a solid, how do I accomplish that, and then join the separate objects into one complete model ready for printing? Thank you in advance for your advice!! Glad to be a part of the forum!

 

P.S. If you need any details about this project, basically I am composing a railroad flat car, and have built the four sides as well as the top deck as separate pieces and will combine them all together as one.

 

2D Base Objects: This is the basic pieces in 2D wire that are drawn to life scale and have not yet been extruded to the proper width.

 

3D Rendering: This is a model i drew up before I realized I might need to make the pieces solids for 3D.

 

I couldnt figure out what i needed to do and how to do it...

2D Base Objects.dwg

3D Render (Example).dwg

[Dadgad]

Welcome to CADTutor.

If you use the EXTRUDE command on non-closed polylines, a SURFACE will be created, not a 3D Solid.

If you EXTRUDE a CLOSED Polyline a 3D Solid will be created.

There is another command which you should try, PRESSPULL.

With it you can very quickly create 3D Solids from non-closed, and disparate entities.

 

This is the link .cadtutor.net/tutorials/autocad/extrude-and-press-pull/ to a tutorial on it from this site.

 

As regards whether or not you need 3D Solids for 3D printing, I haven't a clue, but

wouldn't be surprised if that were the case.

[TurboBoost910]

So since I snapped all of the lines together, they should be closed. I snapped all the corners together, and created an arc for the curved piece. When I extrude them, it is still clear on the inside of the object. Is this considered a solid, or is there a setting I need to activate to make it appear solid instead of a clear 3D object? I am familiar with what the PRESSPULL and EXTRUDE commands do, I just need to know if its creating a solid or not, which to me if it was, CAD shouldn't have made it transparent...

[Dadgad]

Osnapping them together doesn't mean they are CLOSED in this sense.

Although I understand why it would seem to be the case.

If you select a polyline, and check the properties you will find out whether or not it is closed.

Touching at an Osnap or grip vertex is not the same thing.

If you change your visualstyle from 2D Wireframe, to CONCEPTUAL, or SHADED it will apply color to faces.

Wireframe displays as lines only.

Or you can click on an object, and check in PROPERTIES or QUICK PROPERTIES, it will tell you what sort of an entity it is.

 

The one one the left I created with PRESSPULL from your lines.

The one on the right from a CLOSED POLYLINE which was EXTRUDED,

net result exactly the same, disregarding the random heights of the extrusions, as shown in the Quick Properties.

 

Select conceptual visualstyle and they display as shown in the other image.

[Dadgad]

You may want to use the 3DALIGN command when you start putting the parts together,

and if your goal is to have a single item made up of the sum of the bits, then you could use the UNION command.

[ReMark]

At the risk of being crucified yet again (not by you) I would suggest that you check the geometry of your side pieces. I believe you have some duplicate lines and arcs that are sitting directly on top of each other which may have negative consequences on your 3D model when it comes time to 3D print it.

[nestly]

I don't really know much about 3D printing, but a quick search seems to indicate that you should start with a 3D solids (or watertight meshes) and use AutoCAD's built-in utility to convert to a .stl file. This link is several years old, so thing may have changed since then.

 

Print 3D Model

[Dadgad]

[ATTACH=CONFIG]46083[/ATTACH]

I would suggest that you check the geometry of your side pieces. I believe you have some duplicate lines and arcs that are sitting directly on top of each other which may have negative consequences on your 3D model when it comes time to 3D print it.

 

Having run the OVERKILL command earlier on your drawing, I can confirm that there were a few issues you might want to address, should you be so inclined.

Edited January 5, 2014 by Dadgad

[ReMark]

Thanks for the confirmation Dadgad. I think the extra lines may also create problems when it comes time to union the separate parts. What are your thoughts?

[ReMark]

Turbo:

 

Dadgad mentioned the OVERKILL command in post #8. I thought I would provide you with some information about it.

 

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OVERKILL

Removes duplicate or overlapping lines, arcs, and polylines. Also, combines partially overlapping or contiguous ones.

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OVERKILL can be invoked from the command line. It comes in handy for cleaning up drawings.

 

This is an example of what AutoCAD might return after running OVERKILL on a series of lines and arcs:

 

Command: OVERKILL

Select objects: Specify opposite corner: 14 found

Select objects:

3 duplicate(s) deleted

3 overlapping object(s) or segment(s) deleted

[ReMark]

In regards to your question about settings for creating surfaces or solids if you look at the command line during the execution of the EXTRUDE command you'll notice the "MOde" option. This option allows the user to extrude and create a surface (SU) or a solid (SO). An example of changing from solid to surface creation using this option:

 

Command: extrude

Current wire frame density: ISOLINES=4, Closed profiles creation mode = Solid

Select objects to extrude or [MOde]: MO

Closed profiles creation mode [sOlid/SUrface] : SU

[ReMark]

In regards to 3D Rendering, as mentioned in your first post, what you actually did was change the Visual Style from 2Dwireframe to Conceptual. Note that in AutoCAD 2014 there are a number of other visual styles to choose from including, but not limited to, Hidden, Realistic and X-Ray. If we take our 3D model a step further and apply materials (painted metal, steel, aluminum, etc.) to it then we have the option to either view it in a Realistic visual style or to render it in order to see the materials.

 

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RENDER

Creates a photorealistic or realistically shaded image of a 3D solid or surface model.

The RENDER command begins the rendering process and displays the rendered image in the Render Window or the current viewport.

 

 

 

[TurboBoost910]

Al, thanks for all the help! Oddly enough, I couldnt get anything to work with the extrude or presspull to create the solids. I did manage to get the three larger pieces put into regions, which I could then presspull to a solid. The other smaller ones were not coplanar, I found out. Overkill and the other commands did not work.

 

Well, I played around a little and realized that the lines that made the smaller pieces were on different Z axis, so that is why they couldnt be used as a region. For some reason, I couldn't just select the whole object and set all the line values to 0, so I manually moved the lines individually and snapped them to place and then they all formed the object on the Z axis of 0. After that, I got it to work. Don't really know how or why that happened, but that fixed it.