ISO Views, How Useful?

Seems like the primary use of ISO views might be for illustration purposes. Where the scale and actual measurements are secondary to clearly communicating the “purpose” of the object in question.

I have been trying to wrap my brain around the concept. The basic definition goes something like," the ability to see 3 sides in one view". Okay, easy enough! But with most CAD software it is straight forward to manipulate a view to accomplish this. Then I noticed in SU, camera>standard views>iso. The angle looks to be 45 degrees. But looking at drafting standards the definition is: where the X and Z axes are inclined to the horizontal plane at the angle of 30⁰.

What am I missing? What is ISO view used for in SU?

Finally, to my real question, can an ISO drawing in 2d be converted into a 3d version, by tracing over the line work and re-scaling appropriately? I am ignoring the issue of raster vs. vector of the original drawing for now (although important!). Or, is there so much work involved (due to inherent distortion), that it is easier to just re-create the object from scratch, using the ISO for reference only. Case in point, I wanted to model the hanger hardware from this ISO drawing (and yes, I know, it’s in the 3D Warehouse, but I need the practice).

ISO in Parallel Projection is 120˚ between axes…

draw a cube and go from Front to Iso, print and measure angles to see…

in SU you can view in either Perspective or Parallel Projection…

Perspective is best for modelling and PP is best only for 2D output or some types of selecting…

‘match photo’ may work with your example, but I would only use it as reference myself…

john

If it’s 45 degrees, it is technically axonometric.

Both isometric and axonomteric were used in 2D drawing to give some impression of 3D whilst keeping the drafting simple since dimensions remain constant. Using a drawing board and an adjustable angle, you can keep to a set angle whereas with true parallel, the angles would be changing constantly to meet one or more vanishing points.

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This is in parallel and iso, what am I missing? Looks like 90 degrees between axes.

john

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Some useful info: Setting the camera view to Iso when in perspective does NOT set it to an actual isometric view. The camera elevation is wrong. You must select Parallel Projection BEFORE selecting Iso to get an isometric view. If you set up the view in LayOut there is no way to get an isometric view. Setting the camera to Iso gives it the wrong elevation regardless of what projection is used.

Once the view is an actual isometric and in LO, you can set the scale to 1:0.816497 for a 1:1 iso drawing. For a 1:100 iso drawing, set the scale to 1:81.6497. This difference in scale is because LO measures the scale in the image plane, while iso drawings measure the scale along axes going diagonally away from the camera.

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You are missing the difference between the actual angle between lines in the model’s 3D space and the angle between lines as projected onto your 2D display screen. Isometric deals with the latter.

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I occasionally use Iso View when I know I want to add dimensions in Layout. I don’t really like Iso Projection and prefer Perspective views, but dimensions can not be added to Perspective views… yet :grinning:

c07-2019-05 - b05 - proposed steelwork isometric and details - rev a.pdf (1.4 MB)

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I miss Gully. When I occasionally see “cranky” posts from regular posters, it makes me want to create a “Gully Foyle” award.

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I miss him too, but I think that his “crankyness” was mostly misunderstood.

I understand that nobody needs ISO views today except students studying according to totally outdated curriculums that have to produce them as parts of their assignments.

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I know his crankiness was misunderstood. He was a stickler for details, gave great advice and occasionally got frustrated with people that couldn’t clearly explain what they were asking for.
And if you were patient with him, he was patient back. He helped me through a lot of problems when I first started. And his torch has been picked up by all the great helpful people that post here!

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My kids are really into isometric view. Makes it easy to count the number of nubs in each direction to get the right piece (which is another way of saying dimensions are preserved), and makes the sizes of things easy to visually compare no matter where they are in the drawing.

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