Creating a stepped rod


I’ve created a rod in Sketchup. It is 1" in diameter and 16" long. I need to have a couple different diameters along its length. For example, from one end extending in 6.5", I need the diameter to be only .500". For another segment within the rod over a length of about 1", I need the diameter to be .625".

One other segment within the rod (2.5" in from the other end), I need the diameter to taper from the full 1" diameter down to .550" over the course of 2". That’s probably a difference technique. Let me know if I should ask that in a separate thread.



Your best solution would be to draw a profile of one half of the rod, then use the Follow Me command to sweep around a circle.

Some thing like this:

Select the circle, then Follow Me, then the profile.


Ooh @TheOnlyAaron, your turn to type faster than the Sages!


It wasn’t easy! You have no idea how much coffee I drank to be fast enough!


That looks super easy! I’ll give it a whirl. Thanks!



Try taking it intravenously. It kicks in a bit quicker.



Okay. Not as easy as I thought. First, instead of being able to specify the diameter directly, I’ve got to pull up the calculator and get half the value (for example half of .625"). This is not a big deal–just a little inconvenient compared to just using the diameters I know for the various sections of the rod.

Here’s where I’m stuck, though. I started by selecting the tape measure and setting guide points at 2.5", 4.5", 8.5", 9.5", and 16", which is the full length. I figured I could just draw a few rectangles, delete the ones I don’t want, etc., to end up at the final shape (not sure about the taper). The problem is that the rectangles I’m drawing don’t snap to the guide points. Makes me wander what they’re there for.



It’s easier to get the tool to snap to the guides if there are intersections.

Try it this way.

Work on an axis (don’t move the thing back in space like I did for this example)

Draw the rectangle for the profile of the rod. 16" long and 1/2 in. high.
Place the guidelines at the required locations and draw in the shapes of what needs to be removed.
Erase the unneeded edges.
Create a path for Follow Me.
Select the path, get the Follow Me tool and click on the profile.
Delete the path and Bob’s yer uncle.

As for entering the radius, yes, you have to do the math. Maybe it’s easier to work in fractional units or metric. In any case, I think that’s good brain work. :wink:


This is how I was trying to approach it, but after selecting the ruler, clicking on the end point, then typing 2.5" (for example), no guideline appears. What am I doing wrong?


If you are clicking on a point with the Tape Measure tool, you won’t get a guideline. A guideline is formed when you click on an edge instead of a point. You should get a guide point, though. If you aren’t seeing the guide points either, check in the View menu to make sure Guides are turned on.


Got it! Now let’s see if I can chop some chunks out (including the taper).


You can do it.

I didn’t know where the taper went of I’d have included it. :wink:


An alternative approach (however, I think that the “lathe” approach already outlined above is the easiest way to go):


Jim, That’s actually kinda cool. Maybe I’ll give it a try sometime, although I’d rather type in the diameter, but it looks like yours is using radius.

Dave, I’m trying to use the follow me tool. I see where you created a path for the tool to follow. It looks like you just drew a circle. However, when I try to draw a circle, it keeps lying on one of the other axes. How do I get it on the proper axis?



Orbit around so you’re looking down the length of the profile. Once you get the tool showing the right color, hold Shift to lock the direction. In SU2016 you can also set the orientation with the cursor keys.

Note, I drew the circle centered on and touching the corner of the profile. I deleted the face of the circle before running Follow Me. If you don’t do that, you’ll have a hole in the end of the rod.


Here’s a quick gif of changing the view to get the correct orientation.


It appears that nothing is left to be said about actually creating your stepped rod, so I’ll just put this one thought out there: what’s the point of using decimal inches if you’re still going to design in common fractions? Is five-eighths (.625) really essential to the design? Wouldn’t .62 be easier to work with? Or .60?



It will be a machined part, and parts are commonly machined to the thousandth of an inch. The dials on lathes and mills use thousandths, not fractions. Some of the other dimensions in the drawing are .550", .605", .806", etc.


It was a bit challenging to get the “Follow Me” tool to wrap all the way around, but I got it done. Thanks for the help, everyone. It’s a bit tricky to get started, but the more you do, the easier it gets.




Don’t try to drag the tool around, select the circle first, then get the follow me tool and click the profile with it and it will do the full sweep on its own.