Multi segment Air duct pipe conundrum

69 degree elbow.skp (1.1 MB)
As an exercise, and also to have a component for a HIVAC model I was working on, I attempted drawing an elbow downloaded from 3D warehouse. The elbow I downloaded was 90 degrees, but what I needed was 69 degrees. In the model I’ve uploaded, there is the downloaded warehouse 90 sitting at axis center. To the right are examples of what I created. As a base I could work with, I started drawing the angled rings and placing them at their elevations and angle. Many hours of trying to flesh out the pipe; eventually getting frustrated with each attempt. As an exercise it was good. Practice with the tools. Riding the learning curve. Occasionally thinking that if some Forum Folk were watching me struggle, some would chuckle with the knowledge of doing it the easier way. Anyone out there willing to share that way?
I tried making groups of each angled ring and creating a thickness with offset so I had a face to use push pull. Tried Fredo Tools which I find the push pull has little intuitive help.Tried to use Follow Me to extrude a solid group pipe face. Then tried using Solid Tools to trim against each solid group. Lengthy process which had too many problems. So I Ended up doing all the geometry line by line. Much too long a process with the end product having far to many lines visible. I ran Soften on it but then it became too soft or not soft enough. So I made another copy and selected only edges that were not the working rings. Ran soften on those edges and had a better result. But that was a long process that probably wasn’t necessary. Would like to know how the person who modeled the original 90 elbow did it. Or how would you do it?

VBO has his ducting extension on a blackfriday special for $1

One manual method for a 69deg bend with the four segments you are using would be to lay it out with two perpendicular segments and a 2 segment curve then use follow me. Note how I explode the curve, this will give you the hard edges you want. Also note how the radius of the circle will work better when it is less slightly than the radius of the bend. This is not meant as a mathematically correct solution, only a close approximation.

A 90 deg bend could be done with a 16 segment circle and 3/4 deleted.

Here I have done it with thickness.

I just noticed you mentioned using extensions, I thought you were using the web version as mentioned in your profile, if not please correct it.
Fredo’s Curviloft will give you four identical segments at 69 deg.

Thankyou very much for your tutorial Mr. Box.Your first tutorial using Follow Me was the ticket that eventually worked and was a hell of a lot faster than my early attempts. I say eventually because I was having difficulty getting the 2 point arc to perform 2 segments, It insisted on doing a default of 12 thereby giving a smooth arc which auto-filleted the result. Didn’t seem to matter when I would enter 2 in the measure box it would draw a smooth single curve. So I drew an arc away from the object on a flat surface entered the 2 for segments and that worked. When I went back to the flat plane surface it then would draw the 2 segment without a problem. Seems a default needed to be cleared somehow. Anyhow it all went very well after. Thank you again for the knowledge and solution.Figured someone on this forum a had a quick solution in their back pocket.

With tools that have a changeable option, like segments count, you can do it several ways.
Select the tool and before you do anything just type 2 and hit enter/return and then draw your curve.
Or Draw your curve then without doing anything else type 2s and hit enter/return.
You can also change the segment number in entity info as long as the curve hasn’t been modified too much.

Oh and the one I never use, ctrl with - and + works too.

I had tried those solutions and it insisted on creating a smooth arc. I gave a good 15 minutes trying different approaches. I tried making a group out of the profile pre- drawing the arc then opening to edit to no avail. Tried without making a group. After pretty much giving up I went and drew an arc next to the geometry entered 2 and it worked. Then when I went back to the profile and drew on the plane it automatically drew a 2 segment arc. Like it had become a new default. So after reading your suggestions, I just went back into Sketchup and clicked on 2 point arc and it drew a 2 seg. arc without me entering anything in the box. It’s like a new default. Actually as I play around with it now I can’t get it out of 2 segment mode. Even if I choose another tool then come back and choose 2 point arc and enter 12 before drawing it does a 2 seg! Bug?

The 2 point arc tool has a default of 12, but when you change it to 2 it will stay that way until you change it again or start a new session.
Same with circles etc, 24 is the default but if you change it to 48 each subsequent circle will be 48, until you change it or start new.

Okay figured it out . I wasn’t hitting Enter after entering a segment value. Ahhhhhh… embarrassment.

It happens, just remember most things need the enter to activate.