Creating a ledge on a post for circuit board to sit on.

[paulMVAJU]

I found this link, but I did not see what I was looking for.

I am very new to Fusion 360. Also, this is my first post so I am open to suggestions on forum etiquette.

Bottom line the two middle posts will support a circuit board. The post are 4 mm in diameter.  The circuit board is about 1.5 mm thick and the mounting holes are 3 mm in diameter.

I would like to narrow the top of the post by 1 mm in diameter, 1.5 mm down from the top, creating a shelf for the board to set on. I did include a picture of what I am trying to model. 

More info than you might care, we have brown electrical switches. This smart switch only comes in white. I am trying to model it and then 3 D print it. I know there are smart switches that have replaceable paddles. This one does not and it has some features that the others who do have replaceable colors do not. But more important I am learning both 3 D printing and Fusion 360.  This project has really taught me sketches, using the timeline, and editing features. 🙂

[davebYYPCU]

Sketch the smaller diameter on the top of the post, then Extrude > cut the donut ring down 1.5mm.

Might help.....

[chrisplyler]

Or...you know...put all relevant diameters into the same sketch, and extrude the two portions to separate heights.

[paulMVAJU]

if fairness to @davebYYPCU, I did not try his suggestion. From lurking around, if you use sketches to lock down or not seems to be a personal preference. Lot's of debates on best practices. With my limited time of messing around, I have started leaning toward sketches, which is why I tried @chrisplyler suggestion.

Seem to work great, in fact, I changed my screw holes from "a hole" to sketching a circle and extruding around it.  Caught that while watching the screencast. So getting ready to print a test and see what happens.

Here is my current drawing.

[chrisplyler]

@davebYYPCU 's method ALSO involved a sketch. The only difference is that he suggested a new sketch, placed on top of the post, just for the shelf. That presumes you already have a sketch from which you created the post with an Extrude, a Sweep, a Loft or a Pipe function.

Neither method is more right or wrong. It is just my preference to use fewer sketches, keeping things together where possible, and keeping clutter in the Browser and in the Timeline to a minimum, as long as a sketch doesn't become too terribly complex. And I don't think a few concentric circles is too terribly complex.

[davebYYPCU]

There are a few things to add into this discussion, 

Teaching with your file is the best for not creating misunderstandings, cause we are talking to you with your data.   Sure each of us have different workflows that tend to influence answers, and it makes the world go round.

i recommend to new people, one sketch per feature until you know what you are doing will not slow Fusion down.  So lots of small sketches, dedicated to a job, is easier to trouble shoot, and my modelling screen does not become the cluttered area.  

My read of your file, everything in the same sketch, adding another two circles won’t matter, and do it Chris’ way, but you had not done many extrude cuts if any, adding the ledge’s circle in position, was quick clean and simple, both posts cut with one sketch one Extrude, because they existed.  

Many ways to skin the cat....