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Jimmie

What's the best way to set parametric values?

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I just started a new job that gave me Vectorworks 2014 as the CAD package. We have a ton of Mac users, and lighting/event designers, so it makes sense for most of the company, but I do mechanical CAD. I'm used to Solidworks, Autodesk Inventor, and Onshape, so I use the parametric features quite a bit. I'm going to miss the mechanical-specific features of those programs (seeing the mechanism in movement, etc), but I can live with basic CAD. The quick questions I have can be answered with these:

 

Let's say I have a box, and I want one side to be X, one side to be 2X, and one side to be 1/2X, so that when I change X all other sides change appropriately. In Solidworks I just create a variable, and all sides are defined in relation to that variable, so a single change in one variable results in the entire drawing being correct, changing anything tied to that variable. What is the method of doing this in Vectorworks?

 

Let's say I make a mounting bracket and I need 100 of them in a particular installation. Now a designer comes along and says we need to change to a different mounting standard. How do I create an object that when I change one, all others change? In Solidworks I just make it a part, and I just edit that part. It takes only a few seconds to make such a change, but I've not seen anything like that in Vectorworks.

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1.

There are options to constrain geometry but as far as I heard that is not so much fun.

In your example, it looks like you could just scale your object.

 

2.

Do you mean Symbols ?

(aka Blocks, Cells, Instances, ...)

You copy these in your file, if you edit one, all others will follow.

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1. Constraining geometry is fairly close to what I'm talking about. Scaling would work in the given case, but I want a general variable that perhaps a gearbox has a width, and the rod inside is width + clearance, so that when I change the width of the gearbox the rod length will change without changing any other dimension of the assembly (scaling would break it). Another specific example is that if I change the rod diameter, then all the gears on that rod will change according to the new diameter. In Solidworks this can be a single variable, and is trivially easy to do.

 

2. Symbols may be the terminology Vectorworks uses, so that may be what I have to learn. Basically I'm used to creating an assembly, and it gets grouped as an object. I can then create X instances of the object, and I only need to edit the underlying object to make a change to all of them.

 

I'm actually building a gearbox that drives a chain to another gearbox right now for work. I've managed to get a simple model from McMaster parts up fairly quickly, but for me this is basically a sketch without being able to set some of this variables. Having some sort of list of the variables I can change would be ideal, but I can at least work with doing them all individually. This is a relatively simple project, so it's good for me to learn a new CAD program with. I found some info on Vectorscript that looks like it can do some of what I'm talking about, but that's a steep learning curve for a quick project like this.

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The parametric constraints in VW are basically for 2D objects only. I also don't believe that there is an option to contain proportional as you are requesting. There are option to coincident points, Parallel, perpendicular, concentric and by distance.

 

As Zoomer says, Symbols are what you are looking for to simulate parts in Solid Works.  Symbols in VW can be hybrid objects meaning that they can have a different view in Top/Plan than in other 3D views. When a Symbol contains both 2D (and screen plane) and 3D (and layer or working plane)  objects, the 2D portion is displayed in Top/Plan view and everything else is in the 3D portion. If you draw a 2D object in the 3D part it will "fall through" to the 2D part. Similarly a 3D object drawn in the 2D part will fall through. Now way around this.

 

Also, Hybrid Symbols can not be rotated in 3 dimensions, only around the XY plane.  My guess is that you are going to want to make sure you only use 3D/Non-Screen Plane objects in your symbols so you can rotate them in any direction required.

 

HTH.

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3 minutes ago, Pat Stanford said:

The parametric constraints in VW are basically for 2D objects only. I also don't believe that there is an option to contain proportional as you are requesting. There are option to coincident points, Parallel, perpendicular, concentric and by distance.

...

HTH.

 

That explains why I can't get any points to constrain in the 3D view. :-/

This tool doesn't seem to be built around mechanical design, so I guess I can't fault it for not having these features I've previously taken for granted, but it's a bit painful.

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Yes, mechanical design is not the primary focus, and I would not want to design a747 in VW, or for that matter, probably not even a Schwinn (bicycle famous in the US for our non-US based readers), but you can do a lot with it in terms of simple mechanisms and assembly of components, it just takes more effort to keep everything aligned.

 

A work around for your proportional Constraints could be to use the SCALE command to make the change instead of just dragging one side. You can do basic math in most VW dialog boxes, so if you know the current dimension and know the desired dimension, just go into the SCALE Objects command, choose the Symmetric option and just enter Desired/Current as the XYZ factor.  Or even better as I just tried it, use the Symmetric by Distance mode. Click the little dimension button to the right of the Current Distance field and then draw a temporary dimension along the side you know the desired new value for. Enter the desired value in the New Distance field and click OK.  XYZ all scale by the new proportion.

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In my opinion, Marionette is great for creating objects, but not especially good for modifying objects that already exist, especially manually drawn objects.

 

Yes a script (Vectorscript, Python, probably Marionette) could be written that would scale objects from the center (or simulate it by scaling and then moving the object), but you would probably need a lot of script to handle all of the things that true parametric constraints would give you.

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It may be naive of me to think this, but it seems like introducing a type of global variable for holding various common dimensions would be a super great feature for Vectorworks. Such a variable could be managed within the Organization dialog, similar to the way Levels work. For example, a variable "Panel Thickness" containing the dimension "3/4" might be used in any field within the the object info palette that accepts dimensions, such that panel thicknesses, reveal sizes, spacing, etc, might be changed universally in the project simply by updating the single variable.

 

I had the impression that Levels would partly serve this purpose, but It's been frustrating to discover that one cannot bind any arbitrary dimension to a given Level. 

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Soldiworks also uses Parasolid as its 3D kernel so theoretically Vectorworks could have 3D constraints as well if it would license that part of Parasolid.

 

For those not having used 3D constraints in mechanical software it may be a bit harder to see the usefulness of this but it could make things quite a bit easier if you would only have to use a few 3D constraints instead of having to create a parametric symbol by using Marionette or Vectorscript to have the same functionality. Not to mention to be able to keep things together in 3D when adjusting just one object, but that would get VWX a bit more into the mechanical realm of CAD with similarity to parts/assemblies kind of stuff used in mechanical CAD. Though at a basic level I would like to have this in in Vectorworks 3D (e.g. if objects need to be at a certain distance and position from each other and one object of such a group would change dimensions then I would have to manually update the configuration. 3D constraints could take care of this).

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I definitely agree that 3D Constraints would be a great benefit for me. I keep struggling along doing things that would probably be better off in Solidworks or Inventor. Mostly because I know VW and I don't do that much of it.

 

Please enter a wish. I have already asked for this many times.

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Posted (edited)
21 hours ago, mgebel said:

According to the Wikipedia article on Parasolid, Vectorworks is already using it. 

Yes, Vectorworks has been using the Parasolid kernel for a while now, but it is not the full Parasolid kernel nor the same (sub)set of Parasolid functions as Solidworks is using.

 

As far as I can tell Siemens does offer several levels of Parasolid functionality that others can license but not the full Parasolid kernel (i.e. they may want to keep some things exclusively for themselves for SolidEdge such as ST (Synchronous Technology) that I have not seen in Solidworks (at least not in the version that I was using).

 

Of course more Parasolid functionality such as 3D constraints would mean a higher license cost, so it is a bit of a balance between costs and the functionality that VW thinks is useful for or used by its customers.

 

I think VW Spotlight might benefit from 3D constraints given the interdependency of structures and equipment etc. but for Landmark and Architect there are easily situations to be thought of where it would be useful for 3D as well.

Edited by Art V

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