Connecting lines

It there a way to remove the points between lines and make them as one ?

I’m trying to sweep :roll_eyes:

Sadly no Join option available yet :confused: if you create a conical spiral and project it to a plane, it may result in a single line but not sure

edit: It will be a single curve

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I will try it … thanks :smiley:

Hello mr Peter

Unfortunately same problem
I wish you make a tutorial on how to :face_with_head_bandage:


selecting all the wanted sketches for sweep path and then selecting the “to be swept” sketch then select sweep

Seem to jump over my problem :smiley:

I recently made a spiral body using Sweep. I used 90° circle segments instead of 180° ones. You can still do the sweep by selecting each arc segment sequentially.

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180 is easier but 90 is basically 4 different circle sizes in one round.

You are correct. My first large spiral meant to fit on my 11" square 3D print bed was done with 180° half circles. When finished, it looks a little bit oblong. I chose to redo it in incremental quarter circles to make it look more circular. I had to satisfy my critical eye :smiley:

You must have a very good eye because that’s the standard traditional way to create the appearance of a spiral in a volute such as a stair handrail. Quarter circles…

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There was an awesome thread about tapered threads, I hope this can be helpful. The result will be a solid body and you can project one of the helical edges to get the planar spiral shape to guide the sweep

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Back in the day, the only tools available were compass and straightedge. A technique they used still works quite well in the digital age. The simplest method, traditionally using only a compass, is a two point spiral.




The other method used both compass and straightedge. Polygons and lines are used as the basis. The “points” in this instance will be those at the vertices of the polygon.

The first example will use a triangle which creates a 3 point spiral. The appearance is somewhat more balanced than the previous 2 point spiral.




Construction is similar to the 2 point method. Instead of alternating between two points, the center of each successive circle is the next vertex of the triangle. Each new circle is tangent to the previous circle where the common radius lines are parallel. The progression of circles continues until the desired diameter is achieved.


Trimming involves removing 2/3 of each drawn circle. Starting adjacent to the first tangent point as shown. Continue with the remaining circles and construction lines. The initial circle is a tighter radius in proportion to the rest and it’s line may be removed.

Trimming of earlier circles may also be accomplished as each new circle is drawn instead. If while drawing you get “lost”, merely tap the prior circle to show which vertex the next origin is to be placed on.


I have drawn multiple point spirals and have found the 6 point to be the most visually appealing. Construction is identical the the three point. Though 5/6 ths of each circle is trimmed at the finish. Note the distance between spiral lines is 6 times the length of one side of the initial hexagon.




Very nice presentation. The first example uses 180° half circles, hence the somewhat oblong shape. The second example with the triangle uses 120° circle segments, and the third using 60° segments thus making a much more true spiral.

You mentioned back in the day. I started with T-square and triangles, then to a drafting machine, then to my first CAD experience using a light pen and vector display (CADAM developed by Lockheed). I still have my Leitz electric erasure! Here’s a reminder of ‘back in the day’. Good times. (Note: I flipped the image as I am a lefty.) :grinning:


Amazing :clap:

I usually do translate work like a charm

But doing it manually…

Your way prevent errors even manually

Edit …

But wait … how do you sweep like that ?
Doesn’t it come as line regard of the swept shape ?

These are some real ‘old school’ gems! Thanks for sharing!!
I’m loving how the new technology is beginning to merge more closely to manual techniques.
Much as I love my iPad, there’s still nothing like the feel of pencil on a nice rag vellum, though. :blush:

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To MrJack.
My apologies for neglecting the question of your original post. What I demonstrated still results in individual line segments that can’t be joined on the original sketch plane. Sweeping would have to be performed on each segment.

There have been various discussions of spirals in the forum previously. This was an opportunity to offer a simple method of spiral construction that was also a recognition of the traditional compass and straightedge technique.

I am happy the example gave you and others some pleasure. That was my hope.


Oh man must’ve been hard
But that also taught you different techniques :slightly_smiling_face: