Tag: virtual sharp

What’s New in SolidWorks 2014: On-The-Fly Virtual Sharps While Dimensioning

This entry is part 3 of 13 in the series New in SOLIDWORKS 2014

SolidWorks 2014 introduces the ability to find and use virtual sharps on the on-the-fly while creating dimensions.

  1. Start any dimension tool.
  2. Right-click on model or sketch geometry
  3. Choose “Find Intersection”.
  4. Left-click on any model or sketch geometry that intersect the first selection.
  5. The Virtual Sharp element is automatically added, the point is automatically applied as a selection for the dimension tool.

See the attached video below (AVI will open, not an embedded video).

 On-The-Fly Virtual Sharps while Dimensioning

On-the-fly Virtual Sharps (AVI video)

Point Location (Virtual Sharp)

Point Locations by another name, such VIrtual Sharps

The names for dimensioning methods within ASME Y14.5 often do not match the common names.  For example, what most of us call ordinate dimensioning is officially labelled as rectangular coordinate dimensioning.  This can make information about certain dimensioning methods hard to find within the standard.  One dimensioning method that is particularly difficult to find is point location.  A point location is where a point is located by the intersection of extension lines only.  The method is known by so many other names.

  • theoretical sharp corner
  • theoretical corner
  • theoretical sharp
  • apex
  • intersectVirtual Sharp optoins
  • intersection
  • intersection point
  • imaginary point
  • virtual sharp
  • and likely others as well

The SOLIDWORKS application uses the term virtual sharp.  SOLIDWORKS offers a list of options for the delineation of virtual sharps (i.e., point locations). These options are found at Tools pulldown>Options...>Document Properties tab>Dimensions heading>Virtual Sharps subheading.  The only method supported by ASME Y14.5-2018 is the use of intersecting extension lines from two surfaces; so called witness in SOLIDWORKS.

The standard does not require any other identifier or labelling.  Yet many of us do feel compelled to add some sort of label to the dimension, using one of the above terms or their initials.  A label does add clarity, particularly when the scale of a view makes display of a point location hard to read.

Point location

I covered this topic once before from a slightly different perspective in this article: Virtual Sharps.  That article includes instructions on how to create a virtual sharp in SOLIDWORKS drawings.

Virtual Sharps – What do you call them?

What do you call it when you dimension to the intersection of two lines that don’t come to a point? Virtual Sharps?

In the past, I’ve settled on using the phrase “TO V.S.” after dimensions when they attach to virtual sharps. I’ve seen this type of notation used elsewhere. Another abbreviation I’ve come across is TSC, which I assume stands for Theoretical Sharp Corner. I think that might be older terminology.

Personally, I used to prefer the shorter “VS” because it feels like a more commonly understood term. That said, none of this really matters since the standards don’t specify what’s “proper.” For example, ASME Y14.5-2009 uses the term Point Location but doesn’t provide any identification symbols or abbreviations for this concept.

SOLIDWORKS, on the other hand, generously offers a variety of marks to identify virtual sharps. The main problem? These markers are often so small on certain drawing scales or radii that they’re nearly impossible to see without magnification. Another issue is that none of these marks are defined in any standards. And, honestly, a third problem is the hidden nature of the functionality.

You have to know how to create a virtual sharp mark—there’s no dedicated button or icon for it. It’s a short sequence of steps that you’d never guess without guidance. Here’s how it’s done in a drawing:

  1. Select the two object lines that intersect in space.
  2. Use the Point sketch tool.

How is anyone supposed to intuitively figure out that you need to use the Point sketch tool for this? Seriously. But hey, at least SOLIDWORKS provides some method. That’s more than can be said for the standards.

I guess my question is: What are others doing to identify dimensions that reference virtual sharps?

Anyway, here’s an updated article about Virtual Sharps.