Morons Guide to FreeCAD

[joebataz]

Hi Folks,

Talk about a steep learning curve... How about vertical. I am a former middle school mentor who used Fusion 360 in the past and created very sophisticated drawings with my students. I am also retired andwould like to run an engineering class for kids interested in, well engineering. Now that COVID is past, relatively. AutoDesk is being less than cooperative in getting my license reinstated and I'd like to get some simple drawings together to start my summer clubs with. So I looked at FreeCAD.
WOW, right into a brick wall. Been looking at tutorials and none of it makes any sense. I finally got a simple hexagon to draw but couldn't figure out how to scale it or get it to a certain size. Not in mm but in feet and inches. Is there a REALLY simple tutorial, video if possible, I fall asleep reading technical stuff. As I said I've taught basic engineering stuff, my kid graduated with a degree in Aerospace Engineering. He was using SolidWorks on a Windows platform and the schools here mostly use Macs, which is also what I use.
So I would be very appreciative if someone could point me at something that gets me out of the AutoDesk mindset. FreeCAD looks amazingly powerful and I can probably figure a lot out if I can just get to the point where I can actually draw and manipulate objects. I promise once I get going I'll give back and help out as much as I can.

Thanks and stay safe,

Joe B

[chrisb]

Hi and welcome to the forum!

I like your approach. You may have a look at Brad Colette's book "FreeCAD for inventors". It is a bit outdated, but still valid.

As there are many more bad videos out there than good ones, I would rather direct you to the PartDesign Tutorials, where can work at your own pace. If you are interested in advanced sketching, I dare to recommend the document in my signature.

[drmacro]

...

Is there a REALLY simple tutorial, video if possible,

The simplest tutorial...hmm.

The concept is similar to most parametric CAD software.

You have to think in cross sections that are built up to create solids.

So, example in Part Design workbench.

• Select Part Design workbench.
• Create a new document
• Create a Body (this will contain a single, contiguous solid)
• Create a sketch, select the XY_Plane (This will contain the first cross section)
• Create, using the Rectangle tool, a rectangle around the center (where the red and green lines cross)
• Close the sketch
• Click the Pad tool, enter a length, click Ok

Thus a block of solid is born and can be further formed by adding or subtracting with additional sketches.

Have a look at this page for a comparison between Part and Part Design workbench. Scroll down the page to where it shows how to make the same part in each workbench. The comparison shows each step in the progression with associated icons used, you may find it informative. https://wiki.freecadweb.org/Part_and_PartDesign

Have a look at the two MangoJelly beginners tutorial series on YouTube. This 40+ videos should get you going.

[joebataz]

Thanks so much for the advice. Been looking at various tutorials and they are either outdated (don't look anything like what I'm seeing), presented at warp speed or are so complex beyond what I want to start out with; make a hexagon with 48" sides. I am a hands on type of teacher, I have 6 48" aluminum u channels that can be connected at the ends and use it to teach the concept of stable structures. I also teach Lego Robotics for First Lego League and have done mentoring for First Robotics League at the local High School. LOTS of programming in my background, hence my interest in FreeCAD and the Python scripting that will be available when I get a handle on it. Luckily I have about 6 months to get there.
Saw Brad Collette's book but it covers .17, haven't seen an update. I did see another pair of books which are by M.Eng Johannes Wild;FreeCAD Step by Step and FreeCAD Design Projects. They were published in December 2022 and cover v .19.3. They are also on Kindle which is where I read ALL my books. I did see FreeCAD 0.20 Black Book but that one is $57, a little out of my range.
I downloaded Sketcher Lecture and will be taking a look at that as well as the MangoJelly ( GREAT NAME!!) tutorials.
Once again, THANKS for the help! I probably won't be on here while I read away. Don't read as fast as I used to. At 70+ things tend to go a little slower...
BTW, also appreciate the Wrath of Khan (my alltime favorite Star Trek movie, keep your special effects) quote!

Have a great day and stay safe,

Joe B

[drmacro]

...

Difficult to keep books current when the target is constantly moving.

And, there are plenty of old timers here so, 70+ is no big thing.

[joebataz]

Good to know (70+). A lot of the boards I'm on, music mostly (I write music instead of yelling at the TV), consider me a dinosaur...
Real quick questions;
How do I display dimensions? If I want to find the distance between 2 objects, while I'm sketching.
I was trying to draw a line tangent to a circle and the constraint icon (red point on an arc) came up but instead of the line dropping onto the circle, the circle got bigger. Does this have to do with the grid snap being turned?

Thanks,

Joe B

[drmacro]

Good to know (70+). A lot of the boards I'm on, music mostly (I write music instead of yelling at the TV), consider me a dinosaur...
Real quick questions;
How do I display dimensions? If I want to find the distance between 2 objects, while I'm sketching.
I was trying to draw a line tangent to a circle and the constraint icon (red point on an arc) came up but instead of the line dropping onto the circle, the circle got bigger. Does this have to do with the grid snap being turned?

Thanks,

Joe B

Sketching is constraint based. So, in an open sketch you add a constraint. If you just want it as reference, make it so by ticking the Reference checkbox.

[wandererfan]

Does this have to do with the grid snap being turned?

If you are using Sketcher, then concept of a snapping grid isn't very helpful. Sketcher works by solving a system of constraints. Since the circle's diameter wasn't constrained, the Sketcher solved the constraint system by enlarging the circle. If you don't want the circle to grow, then apply a constraint to the diameter.

The Draft workbench is closer to a traditional 2d drafting application, with a grid for snapping.

Here's A solution to the hexagon problem, using Sketcher and Part. No claims that it is the best solution.

[joebataz]

Thanks!

I bought the pair of books and although I'm doing some searching to find what is being described I have made a lot of progress in understanding what is going on and how it's happening which for me is a VERY good thing. The first example in the book was a coil spring which I breezed thru but then I hit the carbinger model and ran into this issue. I had a sneaking suspicion that somehow the grid was the issue but I'm so rooted in EXACT that I like to think I know where things are precisely. FreeCAD is different from Fusion in that respect. I'm going into the Sketcher prefs and turn the grid snap off.
Just wish I could get the dimension stuff to display. Any pointers as to where that option is?

You and the other folks here have been most patient and I appreciate it!

Joe B

[drmacro]

Thanks!

I bought the pair of books and although I'm doing some searching to find what is being described I have made a lot of progress in understanding what is going on and how it's happening which for me is a VERY good thing. The first example in the book was a coil spring which I breezed thru but then I hit the carbinger model and ran into this issue. I had a sneaking suspicion that somehow the grid was the issue but I'm so rooted in EXACT that I like to think I know where things are precisely. FreeCAD is different from Fusion in that respect. I'm going into the Sketcher prefs and turn the grid snap off.
Just wish I could get the dimension stuff to display. Any pointers as to where that option is?

You and the other folks here have been most patient and I appreciate it!

Joe B

I would also note, that grid snap in Sketcher does not produce coincident vertexes. Using the grid snap will invariably create a what the modeling engine will reject as an open profile.

Using the Polyline to make the basic shape (the polyline adds coincident to the vertexes, except the end vertex) is far more efficient. Then add geometrical constraints, then dimensional constraints.