Resize a STL File For Me

[bostonman]

Where do you come up with these oddball layer heights?

Were you referring to me?

If you mean the 0.3mm height, that's the default in my slicing software and what I've used. As for the 0.13mm height, I didn't remember if the suggestion was 0.12 or 0.13, but I didn't realize multiples of 0.04mm was important. Maybe I even used 0.12mm and thought I used 0.13mm. Again though, I didn't realize multiples of 0.04mm was important until now.

If you're asking about the two different tools, the 'revolution' is an additive action while the 'groove' is a subtraction action.

Yes, that's what I'm asking about. Let's say I wanted to make diagonals, not necessarily threads, just  45 degree angles all connected together. I could draw a horizontal line, go up 45 degrees to the left, 45 degrees to the right, etc... draw a line back to the z-axis, and down to the 0,0 point. Now perform a revolution and I have the same as I would with groove (or believe I would).

Using 'groove' is still an uphill battle for me due to not grasping the whole tree structure. I create a sketch, then a pad, then another sketch, etc... I can follow the 1-2-3 steps, but I don't grasp the whole concept.

[MarkF]

All you need to do is create a body, then a sketch of the profile, and do the revolve.
Note:  You can't cross the axis you're going to revolve around or it will fail.

Watch this:
  https://youtu.be/eP_pMWu25tM?list=PLWuyJLVUNtc0UszswD0oD5q4VeWTrK7JC&t=540

[MarkF]

It would behoove you to watch his entire FreeCAD series.

   https://www.youtube.com/playlist?list=PLWuyJLVUNtc0UszswD0oD5q4VeWTrK7JC 

It's a serious commitment of time but well worth it.  It took me about four days to watch.

[bostonman]

Not crossing the axis makes sense.

I'll have to set aside time to watch the videos. Typically if I don't grasp the concepts or the foundation, I tend to not retain the information well. Hence why I keep getting stuck on basic concepts, however, I know what needs to be done in order to create a part based off a mental image.

3D modeling I grasp. I've explained the basic concepts to friends when I've printed something and they stare at me like I have three heads, but I think the tree structure is what throws me for a loop; especially when I view designs by others.

[MarkF]

I can't say that I have ever looked at someone else's FreeCad model.  I've always just watched them developing the model and seeing the process and not paying much attention to the tree structure.  I use the tree structure mostly to go back and edit previous parts of the model.  Not so much how it is built.

The only way I tend to learn is by 'doing'.  I do go back to videos to see how something is done and then doing it right away.  Just did a quick look and found that I've done 180+ models over the past several years.

I see that FreeCAD v1.00 is in release candidate and looking forward to seeing what's new.  Just the topological naming problem mitigation will be a welcome fix.  I'm always modifying something that adds a extra edge and breaking the whole model.

[bostonman]

You're absolutely correct about learning by doing.

I don't necessarily follow the tree structure, but uncertain how to avoid it. In the case of this knob, the dimple on the face and the shaft hole needed to be changed. Ignoring that the tree names could be changed to make it more obvious, I find myself questioning why 'revolution' is above 'sketch'. Seems to me 'sketch' would be the parent part of the model and 'revolution' is a sub design (since it was done second).

When I made the acorn cap last night, I realized it was easier to delete the 'revolution' from the tree and return to the 2D 'sketch'. Prior I was looking at a series of constraints, lines, etc... that didn't make sense.

Again though, no idea why 'revolution' is sitting above 'sketch' in the tree structure, but just emphasizing why I get confused.

[MarkF]

You have to pay attention to the indentation.  With the arrows, you can expand and contract tree branches.  The expanded revolution shows what was revolved.  The same with pads.  Expanding the pad shows what was padded.  etc.
The tree structure shows the sequence but also the sub-branches show the makeup of the higher branch.

[MarkF]

I was thinking of FreeCAD's tree structure and my understanding of it.

• It is NOT a list of instructions for building a model.  As you would find in a set of Ikea shelves.
  
  
• The tree shows the dependencies within the model.  As you go down the tree (at the same level), each item is dependent on the one above it.  Each sub-level/indentation contains the items that makeup that branch.  For example, the sub-level for a fusion shows what was combined or a cut sub-level shows what was cut from what or a compound shows all its pieces or etc.

Maybe that helps your understanding.

[bostonman]

The tree shows the dependencies within the model.  As you go down the tree (at the same level), each item is dependent on the one above it.

This does help.

I think it's decades of seeing a tree structure for a Windows directory that's confusing. When I see 'sketch' under 'pad' I question: how can a pad exist when it was created after the sketch.

Interpreting the design from others is harder I think. Currently, as it has been, I can handle padding a 2D object and managing the tree somewhat. It's doing the fancier stuff like adding a second piece to a part that I don't grasp. Also, sometimes I've exported to a STL and I get garbage in the slicer software. I end up highlighting different things in the tree until I get a STL that makes sense; so I haven't understood what I need to highlight. In the past I believe I did a CTRL-A and got a junk STL, and then I've highlighted the last thing in the tree and got a good STL; but don't hold me to this as I don't remember exactly.