How do I miter steel tubing of different sizes?



I’m new to SketchUp in general but I went to school and took several autocad classes about 10 years ago so bare with me please.

What I’m trying to accomplish is to miter the joint between two different sized pieces of tubing but have them maintain them as individual objects, like a coped joint in trim carpentry. Can anyone help me with this task. Thanks a lot!


It’s hard to know how to answer, as a coped joint and a mitered joint are very different things. In a mitered joint, two pieces meet at an angle, and their ends are beveled so that they meet along the bisector of the angle. In a coped joint, the end of one piece is cut to the negative shape of the profile of the edge on the other piece. In SketchUp it is quite easy to draw a mitered joint, considerably harder to draw a coped joint. So which is it you really want?



You’re absolutely correct, they are two different things! I apologize for that. I’m looking to cope a joint. Is that reasonably possible without reinventing the wheel?


It is pretty simple if you have Pro and can use the solids tools, somewhat more complicated if you have Make. Here’s the process for Make:

(note: I will call the piece with the end to be coped the “rail” and the piece with the profile to match the “stile”)

  • Create the two pieces and make them Groups or Components. Shape the edge of the stile to the desired profile, typically using pushpull or followme.
  • Scale the two pieces up by a factor of 10 or 100 (to avoid issues with creating small geometry). This is easier with Components because you can make another instance and scale it then delete when finished. With Groups you have to apply the inverse of the original scaling.
  • Position the two pieces correctly with respect to each other (they will overlap but not interact)
  • open the stile, select all the geometry in its profile edge, and copy it, then close the stile
  • open the rail and invoke “Paste in place” to add the profile geometry to the rail’s group.
  • select all inside the rail (still open for edit) right-click, and select Intersect Faces with->selection
  • after the intersection completes, delete the stray geometry where the profile juts beyond the ends of the now-coped rail.
  • scale the parts back to the real size

If that is too confusing, I’ll make an animation of the process - I have to leave now and don’t have time.


<img src="/uploads/default/original/2X/2/2cea0b3dc2feaec99dfe2f3bfc3b1e8e560033d9.png" width="690"height=“392”>

While waiting for Mr. B to return, here’s a method using only native tools that can be done with any version of Sketchup. Working from the left:

1.Place tube components as needed. Let the tube being coped be plenty long. The waste side won’t cost anything and you won’t be filling the scrap bin.
2. Open the tube that isn’t getting coped and copy the outside surface to the clipboard with Ctrl+C (Command-C on Mac). Close this component to get out of Edit mode (use Esc). Then hide that component to get it out of your way for the moment. Open the other component which is getting coped and use Edit>Paste in Place to paste the copied surface.
3. Select the surfaces, right click and choose Intersect Faces>With Selected. Edges will be formed between the crossing surfaces.
4. Erase the tube on the waste side of the cope along with the surface from the other tube. Correct the face orientation in the coped area.
5. Unhide the other tube.



I’m assuming this method would work equally well with tubing that doesn’t intersect at a 90 degree angle? Most of the joints that I’ll be drawing will need to be at an acute angle.


Yes. It’ll work with tubing that is at other angles.

Keep in mind that since SketchUp represents circles with a polygon of 24 sides (or more if you choose) the cuts can look a bit jagged. It probably won’t be a problem unless you are making close up views of the joints. You can make them look smoother by increasing the number of sides used to draw the circle for the tube but be conservative. Increasing the number of sides might make things look smoother but often that comes at the cost of more complicated work and reduced computer performance. Find a good balance that works for your needs.


Also don’t work with very small dimensions.
SketchUp’s tolerance will baulk at 1/1000".
So any edges with start/end closer than that are not be made by native-tools and plugins.
So reliant faces also get missed out.
So if you work with very small dimensions, very tight angles, tiny bends etc, then consider scaling the parts up x10 or x100 and doing the intersections etc - after the processing scale-down back to the original.
Small geometry can exist - but it cannot be created straight-off…


I just wanted to say to everyone, thanks for the advice. I’ve been a member of only a handful of forums in the past and this is by far the best and fastest response I can remember ever receiving. I now know what I’m going to be doing tonight after work :smiley:



I’m attempting to you use method right now but I have one more rookie question. How to I ensure that the face surface I copy and paste goes back exactly where I took it from? Everytime I’ve tried to paste it back into the drawing it always follows my cursor. Thanks


Use edit option “Paste in place”


Box beat me to it. Reread step 2 in my description of the process.

“Open the other component which is getting coped and use Edit>Paste in Place to paste the copied surface.”

At least for my use, Paste in place gets far more use than regular old Paste.


Tip: You can customise the keyboard shortcuts; personally I have [ctrl+shift+v] set up as “paste in place”


Good tip. I use Shift+V for that.


I use ctrl b as it’s next to v.


On a Mac, regular paste is Command-V, so I use Ctrl-V for paste in place. That would be an issue if I switched back and forth with Windows, though :grin:


Be mindful of segment orientation when creating the initial geometry.
Regardless of whether the tubes are the same size or not, symmetrically aligned geometry will produce a cleaner intersection.