Rounding angles < 90° with predetermined radius

[jwr.rom]

I am looking for a method to round off angles smaller than 90° with a predetermined radius.
For angles of 90° this is not a problem and you can use SU’s native tool or an extension.

Only for angles < 90°, I am looking for the right method or extension to round them with a predetermined radius. Currently, I create a circle with the desired radius and connect it to the two planes. This works but is very laborious to make this nicely.

Possibly someone can help me further with this. Thanks in advance for any suggestions.

[ateliernab]

Well you can do it with the 2 point arc tool, and double clicks.

I was going to start explaining it all but remembered Aaron did a video on it some time ago

Double Click - Skill Builder

and yes, works with acute and obtuse angles, as long as there is space. it’s really handy.

[francisquitof]

You can also use fredo corner or round corner.

[ateliernab]

nope, it won’t work.

he’s not talking about rounding existing edges, he’s talking about rounding 2d corners.

Fredo’s solution is rounding between faces.
(and I’m pretty sure he’s already got it, looking at the pictures)

the 2 point arc + double click method solves everything here. I’ve been using it for exactly this need for quite some time now.

Using the 2 point arc, you round one 2d coner the way you want, then by double clicking (with the tool activated) on other 2d corners it’ll reproduce the operation. It’s quick, simple once you get it, and it’s vanilla, no need for extra tools.

[Guido]

I use the offset tool to give 2 equidistant lines or arcs then use the arc tool or pie tool (then remove the perpendicular) set to the offset to make the required arcs. Be careful of the number of segments though because the arcs might look like they touch but sometimes there is a minute gap that prevents the union of the arcs and lines.

[ateliernab]

@Guido

I use the offset tool to give 2 equidistant lines or arcs then use the arc tool or pie tool (then remove the perpendicular) set to the offset to make the required arcs. Be careful of the number of segments though because the arcs might look like they touch but sometimes there is a minute gap that prevents the union of the arcs and lines.

again, with the method shown at the start of the video, you don’t get gaps, and you don’t need to offset, just a guide line if you want the curve to start from a specific point.

EDIT : just noticed your profile says Make 2017, and suddenly doubt comes to me, I don’t remember if this method, and the subsequent double click method worked already then. But if id does work, I find it better than offset, you don’t need to find the centre point to make curved corners.

@jwr.rom check from minute 1 to 3, it should solve your issue. (the rest is worth watching too)

[DaveR]

A couple of other options to consider:

You could use the 2D Fillet tool in TIG’s 2D Tools to draw the arcs of the desired radii. You just click on each of the joining edges and it draws them. That’s very quick and the tool remembers the radius so you can bang around the 2D drawing and round the corners. It’s a bit faster than using the native 2-Point Arc tool.

One thing I often do, especially when I want arcs that are tangent to each other is draw in temporary arcs or circles and use TIG’s Tangent Tools to figure out the true tangents. Then I replace the temporary geometry using the Arc tool to draw arcs that meet at the tangent points. This is one model in which I did that.

[TIG]

https://sketchucation.com/pluginstore?pln=2Dtools
https://sketchucation.com/pluginstore?pln=TrueTangents
Both available for free download, free membership possible.
Donations welcomed and Premium memberships offer freebies etc…

[DaveR]

Thanks, TIG. I was going back to get those links but you beat m to it.

[jwr.rom]

Good evening all. Thank you so much for your input, tips, and suggestions! I did not expect to receive so much useful information so quickly and so much. Top!

@ateliernab As for using the Fredo Round Corner; That’s right. I am using this extension. You saw that correctly

I’m going to try them all out and let you know what works best for me. Regards, Jan-Willem

[jwr.rom]

Good morning Pierre,

I watched the video and tried to apply this method to my design, but it doesn’t quite work.

Creating one rounding and after double clicking also removing the two redundant lines sometimes works. But to then apply the same operation to the remaining corner does not. I made a video showing my actions. In doing so, I also provided some commentary, so turn on your speaker.

In addition, I attach the design as an example. I am using SU 2023 and working with it on a MacBook Pro M1. Possibly I am overlooking something.

Regards, Jan-Willem

Video
arc test.skp (149.8 KB)

[mihai.s]

[ateliernab]

haha, yes, circles, what a messy shape.

ok, first, the fact that the extra bit doesn’t dissaper is not an issue. from time to time, the extra bit will remain. you can delete it.

the issue you’re getting is that this method will try to put the curve on both lines that form an angle. and because you’re trying to join a line and an arc, you’re getting a problem.

so let’s say I make this. a 2m radius arc (notice how using a guide allowed me to pick the distance of my arc)

When using the same parameter on an acute or an obtuse angle, it’ll require more or less line to draw. You can see that on the acute, it’s 5,4m while the obtuse only needs 0,7m

and that’s where your problem is. at 90° you’ll need 2m. lower than 90° you’ll need more length.

Here in your first problematic place, you can see that because of the first circle segment, you are limited to 1,883m radius. so off course your 2m radius won’t work.
and that’s exactly what Mihai is showing in the video, take a smaller radius, then suddenly it works.

When working with cuves like yours, you’ll need to pick a rounding that’ll work with the smallest of your angles.
in my example, 2m was too much, but 1,883 was ok (simply going from the tip of the segment)

(here is another example, you can see that if I force the 2m radius, the last segment on the right is too short. so I should have done exactly what you did, make the rounding from the second segment)

In your case, you might have to do it manually (wit this technique at least) on these angles.

[Wo3Dan]

@jwr.rom

Possibly I am overlooking something.

Yes you are.
Look closely, your “arc tangent point” (so to speak) exceeds the length of one segment of the curves that you are trying to include in the rounding.
Try the same with a smaller magenta tangent arc and you will see that it works in more or even all cases in your example.

In other words, carrying tangent from one corner to another corner only works on segments running from one mutual endpoint.

And as for removing the corner geometry at the end of the operation, the will only happen if the mutual endpoint of the rounded two segments is not also the endpoint of other connected edges at that point.

Rounding off corners works as expected if you fully understand what SketchUp is doing.

[ateliernab]

@francisquitof

You can also use fredo corner or round corner.

actually, it made me think, and yes, you can. in a way.

what you can do is take your 2d unrounded shape, and make it 3d.

then select the 4 verticals vertices that you want to round. and go do some fredocroner.

then when you’re satisfied, simply keep the top face (either copy it on the side, or delete the rest)

it’s extra steps, BUT you’ll be able to use the full power of Fredo’s tools. circle, squircle, straight line, you can have different radius and segment count for every corner. but you’ll need to go 3d first, as it doesn’t work in 2d.

[DaveR]

@ateliernab

I avoid this situation by using the method I described above with TIG’s True Tangenets.

[jwr.rom]

Thank you so much again for all your input. I learned a lot from that and now know what was the reason for not displaying correctly plus how to fix it!

It might be an idea if Aaron discusses several options like you have given in a new Skill Builder in addition to the double-click method. After all, in industrial design, this is a regular occurrence.

I only run into two things that I think have to do with my configuration (MacBook Pro M1 / SU2023)

Double-clicking to apply an arc to multiple angles (Skill Builder Double Click) usually does not work for me for angles larger or smaller than 90°. As @mihai.s Mihai demonstrates, it absolutely does not work for me.

In addition, the 2D Tools extension crashes on multiple options (the familiar beach ball appears, and I have to forcefully close SU). Fortunately, the ‘2D fillet’ option does work. @TIG TIG Is it true that my configuration is having trouble with your nice extension yet?

Greetings and have a happy Easter!

[Wo3Dan]

@jwr.rom

Double-clicking to apply an arc to multiple angles (Skill Builder Double Click) usually does not work for me for angles larger or smaller than 90°.

In other words it only works on angles equal to 90°?

Look at my posts above and also the attached screenshot. Native SketchUp ‘2D-Arc’ double click should work (as shown) for all angles, taken that both segments closest to the mutual endpoint aren’t too short.

[jwr.rom]

I did not express myself well. Sorry! The answer to your question is no.

I find it difficult to explain. I certainly looked closely at your screenshot and also understand that this is how it should work, but on my system, it just doesn’t work

See the video. I am also attaching the file that failed on my system. Hope this helps clarify my experience.

double_click.skp (80.2 KB)

[ateliernab]

edit : Wo3Dan found what the problem was, the arc being an arc refused to cooperate. my bad.

with angles like this I usually do it by hand, angle after angle, because an identical radius will give different-looking results. and the final look is as important as the mathematical rigour here I think. (at least when I do it)