Curved pipes

Can you please tell me if I need help with modeling in 3 demensions

Tubes as an example when they are bent in 3 different directions. How to draw a sketch and which “Plan” to use?

Hi, instead of creating 3d curves, any 2d curve can be projected onto surfaces as edges, even if it is a curved surface. The result will be an edge element, that can be used as a rail for sweeping around 3d shapes

Thank you very much, this is the way I use it, isn’t there an easier way to work with bent shapes?

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Well, the chaotic lines are understandable, here is a specific example of brake cables on a bicycle. Can you explain how to build lines in these planes?

Not sure if I’m missing the point here. But do you mean something like this?

I do quite a lot of proper wreathed hand railing and the geometry can get interesting. Especially because the shaped section of the handrail has to follow the centre line, but unlike this section, it has to stay horizontal laterally.

Often the wreath has to predictably and accurately traverse some interesting lines as below.


Edit: I should have said in this case I created a distorted cube and drew sketches on each side for the sweep tool to follow.

My method really doesn’t use planes per se. You can start with one plane to draw the initial line. as you finish one curve, simply select it’s end point to start another curve and then use the move/rotate tool, moving the center to the connecting point of the 2 curves and rotate it. and then select the end curve point to add a new curve segment and repeat.

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Thank you very much!

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Thank you very much, both methods are working

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No problem. If you ever need to describe a line over a defined curved plan, but that falls at a given or at different rates, this can be defined accurately too. The plane sketch system used by Shapr3D lends itself quite well to it, though I do yet have to experiment with irregular sections being swept in any of these cases.

Sweeping to a different geometry would be handy. Loft can but I haven’t found a sweep tool that will so far.

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Yes and I find loft can give unexpected results between the section drawings.

The methods of defining a sweepable line are a bit different depending on what you’re after. In handrailing the problem is how to carve a potentially helical curve out of flat planks of wood. The basic principle is based on the ideas here oblique section through a cylinder produces a true ellipse. In fact you can do the same with an elliptical or even naively curved cylinder.

Any segment of the oblique cut is obviously on a single plane, and you can use sections of the curves between the apex and base ends of the sloped shape to make any line you want. With most applications it’s necessary to keep the segment’s plan angle at 90°or less for any practical use.

I’ll try and do a demo when I get a mo.


We are happy to see your results! You do nice work. The main reason I contribute is to teach myself. Trying to help others is the next best reason. I have a project I’m working on where I could use a team.