Bending a spring

Hi all,
It’s been a while, and hoping all is well. Another stumper for me today please. I have to model the attached light fixture for a render I am working on. Not sure where to start. I drew a row of circles and my first attempt was to bend this group using TrueBend. (LOVE that extension!) Sadly, it is bending my group in the oddest of ways and not at all what I was hoping for. Any suggestions as to how I might go about this please?

You could do this with truebend, which bends on the red axis so perhaps your component axis is not set correctly if you are gettin unexpected results. However this will also distort your loop geometry to be non uniform (wider on the outside) and also be more complicated than necessary.

I think I would do this with a simple combination of follow me for the wire loops and radial array. Here I copy rotate the first loop and type in 360, effectively coming full circle, then I can type /12 to iterate 12 copies evenly in around the circle, the advantage is that I can continue to type in /x to try populate with different numbers of instances to my liking.


Actually I was about to come back here to write, “Thanks but never mind. I figured it out by changing the axis.” - then saw your reply. At least I figured it out. Now to try Fredo6 Fredoscale to see if I can manipulate those rings to match my picture. Thank you so very much for responding. :grin:

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PS: I actually use radial array a lot as I do a lot of work with event seating - dining tables etc. That method will give me a nice 360° circle, but the challenge was/is now to bend those circles as in the shape of the light fixture. I am sure one of the Fredo6 tools would do it, but not sure which one. I shall experiement. I tried with one of them and ended up with this. Pretty for sure, and will no doubt come in handy down the road, but not what I needed.

Do you mean the shape of an individual wire loop? Looks pretty close to pill shape to me, close to parallel walls with arc ends, you could make the sides shallow arcs too if desired. If you need to match the shape exactly then bring the image into SU and model your initial follow-me loop on top of it. Use Tangent locking on the arc tool to trace a series of arcs around the loop.

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I meant getting the loop to pinch the way that one does. And do you know the worst thing about working in SU and for that matter even Photoshop depending on what I am doing… being a math moron! And I am that in spades. But it’s the pinch that’s my next challenge. You are being so patient - thank you. If you are like me, I love a challenge, so always up for one. I finish all of my sketchup work in Photoshop, so I could easily remove the background from the original picture and just composite it, but that would be cheating.

Pinch? Describe the pinch, I don’t understand which part that is. How the shapes converge at the top around the hanging point?

See where it narrows in the front? Almost like the top of the volcano. If in real life you took that circle of rings and pinched it at the top at that point to bring the rings closer together, you would get that “pinched” effect.

Here’s a view of the lamp from a different angle.

I think @endlessfix is on the right path.


That pinch is a function of where the center of your radial array is. Place the Axis of rotation at the hanging point for a copy of the photo. (2)


Jealous. I guess if I had more time to really learn all that is so in depth with SketchUp I might one day be a shadow of what you are and can do, but for now I struggle along with help and grateful for it all. This looks so good!!!

Thanks for the compliments but that image has nothing to do with SketchUp. I just went looking for other images of that lamp. I was hoping for a top view but this was as close as I could get. It looks like what Riley has been showing.

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I am going to try this tomorrow. Again… a math moron and to include geometry so SU is a challenge for me. I hope I can get it right, but I won’t give up. To be cont’d - and I shall return with either my success, or my dismal failure. Thank you and goodnight. :confounded:

It’s not that complicated, you can certainly do it. Re-read the previous posts and watch the gifs then take it one step at a time. There are no fancy extensions involved, no math either :wink:. I unusually encourage other users to try and learn for themselves, but as I was going to trash the file, I figured I might as well share it as a reference for you. But do try, you can do this!

Untitled.skp (369.1 KB)

Coming up with some really interesting shapes this early morning, but not there yet! I shall prevail! But not now… later… :upside_down_face: Mornings are a bit of a rush so I shall go through all the suggestions in detail later. Ta.

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Kathryn, I’m late to the party as always… Keep to the advice Endlessfix gave and you’ll get there. Had to have a little play with the light. The skewed perspective of the pictures made it a little difficult to come up with a profile for the wires that suited me. the rest easy peasy. The profile I came up with is on the right.


You know I tried that! That was the shape I used this morning and the result was what you saw in my last post. Just sat down with my cuppa, and going to try a few more things. The render that this was to go in has been finished and sent off, but I really really dislike unsolved problems and love a challenge, so I am going to keep on until I get this right. I do have one more idea… Hmmmm. And I totally agree re the light perspective. I had a rough time actually seeing that it was a full circle and not something that was just somewhere in the region of 270°.

Kathryn, sent you a private message….

Sometimes… not always… it pays to be doggedly stubborn - lol. Still got to tweak a little, since the centre column is not thick enough, and now that I have a method, I will make my tubes/spokes a little more finished and smoother, but I think I’m getting there! Do I say “Eureka!” or “Drop the mike?” Don’t know what I would do without the inspiration on this forum. (Screenshot won’t upload - trying.)

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