Difference between revisions of "FreeCad Tips for Beginners"

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= Basic Shapes vs Sketches =
 
= Basic Shapes vs Sketches =
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My instinct at first was to start with basic geometric shapes and then combine them.  So, for example if you wanted a shape with a large cylinder at one end and a long thin cylinder at the other ( like a simplified machine screw ) you might actually make 2 cylinders and create a fusion.  With a sketch you draw the cross section and then revolve it.  As the cross section gets more complicated the sketch based approach may seem easier.
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Sketches can generated shapes in several ways:
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*Pad ( or for negative shapes pocket )
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*Revolution
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*Sweep
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*Loft
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== Based on Basic Shapes ==
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== Based on Sketch ==
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Links
  
 
= "Tricks" I Use =
 
= "Tricks" I Use =
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*'''[https://hackaday.com/2014/02/05/3d-printering-making-a-thing-in-freecad-part-i/ 3D Printering: Making A Thing In FreeCAD, Part I | Hackaday ]'''
 
*'''[https://hackaday.com/2014/02/05/3d-printering-making-a-thing-in-freecad-part-i/ 3D Printering: Making A Thing In FreeCAD, Part I | Hackaday ]'''
 
*'''[https://plus.google.com/communities/103183769032333474646 FreeCAD - Google+ ]'''
 
*'''[https://plus.google.com/communities/103183769032333474646 FreeCAD - Google+ ]'''
 
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*'''[https://github.com/FreeCAD FreeCAD ]'''  This is a very important link.  It contains the code for the package, but also much other stuff, macros, parts library.... Check it out.
  
 
== Tutorial ==
 
== Tutorial ==
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= End =  
 
= End =  
  
[[Category:FreeCad]]
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[[Category:FreeCad]]  [[Category:CAD/3DPrint]]

Latest revision as of 07:29, 26 January 2018

This is an article started by Russ Hensel, see http://www.opencircuits.com/index.php?title=Russ_hensel for a bit of info. Look at the page history to see if I am still actively working on it. If not I still may come back at a later time.

Introduction[edit]

FreeCAD is a nice, powerful, Python enabled, free, open source 3D Modeling Program. It is not cloud based, it needs no Internet connection. It is however not finished, not well polished, and not entirely intuitive. It does have a community devoted to its use and development. Despite the shortcomings it is a very nice program ( and getting better). This instructable is a supplement to other tutorials and tries to fill in some gaps, expose some gotchas, and give you a mental model for using the program. There are lots of useful web pages and tutorials on the program, see the Links section and check them out.

How To[edit]

To best understand this document you should:

  • Install FreeCad
  • Download the Files from this instructable ( will be at github in a bit ...... )
  • Work along In FreeCad as you read the information here
  • Look at the other FreeCad links I have provided.

The files I have provided are easy to mess up if you open them in FreeCad and make an unintentional change. So keep the files in a safe place and work on copies. If a file seems messed up delete it and make a new copy from the original.

+ FreeCad Orientation: Look at the Object =

Lets open FreeCad and then open the first file: object_1.FCStd ( use the menu File → Open ). This item is not a anything useful, but it is just complex enough to illustrate a few of the techniques of making objects in FreeCad. It is a combination of a sphere, rectangular solid and cylinder. It has a long hole drilled down through its length. Lets take a look at it.

<Image of objedt>


Gotcha – the FreeCad User interface is highly customizable, I am using it here just as it default downloads and installs. Use care if you modify the interface; I have not found a one button way of returning it to its default state ( aside from a clean installation ).

Just below the menu is a list of icons that looks like this:

< icons >

Each icon has some pop up ( or hover text when the mouse is over the icon ) that names the icons function, I will use these as names for the icons. The first icon (Fits the whole contents on the screen ) should be pressed on pretty much any occasion you are having trouble figuring out what is going on. This is because FreeCad can easily get zoomed in way to much, or on the other hand, zoomed way out. Either can stop you from seeing anything like what you expect; tis is another Gotcha.

Farther along there are a series of icons that rotate the object ( this can also be done with the mouse or keyboard key, but that is more confusing, so learn how later ) The first of these icons ( Set to axonometric view ) is often good for a general view of the object. The rest set the view along one of the three axises ( x, y, or z ). ( Set to bottom view ) is one example. Try them all. Get comfortable.

Using the mouse, its buttons, and some keyboard keys it is quick and easy ( once you have memorized some stuff ) to pan, zoom, and rotate the point of view.

I would not begin that way but instead use the icons just below the menu bar as shown in the picture for this step. Each icon will display some text explaining the icon if you put the mouse over it. So much less to remember.

Try looking at the object from different directions. Use the icon to make sure the object fits on the screen ( Icon test: Fits the whole content on the screen )

Mess with the mouse if you wish ( try both button, mouse wheel, ctrl, shift... ). You can always get back to a reasonable view with the icons.

Note that FreeCad can either change an object or create a new object. If you have a cube you can change its dimensions. If you combine 2 cubes then you create a new object that consists of the two original cubes that retain their own identity and which can still be modified, these changes then trickle ( up? ) the model and change it. This is real useful. If you delete the combined object the 2 components are not deleted but can be reused, or deleted themselves.

What a Simple Object is Made of: Look at the Components[edit]

Find the Combo View Panel, if you have trouble finding it look at the menu: (View → Panels → Combo View checked ) Also note that panels can be resized and pushed around in the FreeCad window so it could be a bit hard to find. Click on “Model Tab” at top of the Combo View Panel


< image of tree view >

Fuse Difference

Any 3D solid is a drill or a punch. You can “machine” parts using any solid a a tool.


Name/Rename Your Components[edit]

Basic Shapes vs Sketches[edit]

My instinct at first was to start with basic geometric shapes and then combine them. So, for example if you wanted a shape with a large cylinder at one end and a long thin cylinder at the other ( like a simplified machine screw ) you might actually make 2 cylinders and create a fusion. With a sketch you draw the cross section and then revolve it. As the cross section gets more complicated the sketch based approach may seem easier.

Sketches can generated shapes in several ways:

  • Pad ( or for negative shapes pocket )
  • Revolution
  • Sweep
  • Loft

Based on Basic Shapes[edit]

Based on Sketch[edit]

Links

"Tricks" I Use[edit]

  • Visibility You sometimes may loose track of which part of a model you are looking at. Parts can sit on top of each other making things even more confusing. What I do: Make everything invisible ( ) then click on some part of the model outline and use the space bar to toggle the visibility of the parts you are interested in.


Look at Other Peoples Models[edit]

Download models and examine them. Some places to look:

  • one
  • two
  • buckle my shoe, coming soon.


Youtube Video[edit]

There are a lot of good ones. I find the ones without narriation useless, your results may vary. Some I like:

  • one
  • two
  • buckle my shoe, coming soon.


Written Docs[edit]

  • one
  • two
  • buckle my shoe, coming soon.

Gotchas[edit]

Cannot See Anything[edit]

  • Everything may be set to invisible.
  • Press the icons for isom... and size object to fit display.
  • May be in middle of a long running operation, be a bit patient.

Cannot Delete Object[edit]

This seems to happen to me too frequently. Perhaps I misunderstand something. In any case I close the file, reopen it, and things seem to work.

FreeCad is Acting Strange[edit]

If closing and opening the file does not work then close and open FreeCad. Often works, sometimes not, error may be yours or FreeCad.



Gear Part PartDesign Mesh

Cutting out unnecessary material in a gear

Circular holes or other regular shapes Using sketches for holes

Additional Links[edit]

Tutorial[edit]

Lots on youtube, search there, I will try to get to explicit links later.

End[edit]