Drawing small parts in Content Builder

[nestly2]

Using Content Builder in AutoCAD MEP 2013, I am unable to create any geometry that is under about 1.5 units (inches) or within about 1.5 units of another point.  It doesn't matter if the point is picked with the mouse, or specified via absolute coords, the geometry is either not created or it snaps to the nearest existing point.  The min distance also seems to increase the longer Content Builder is open, with the unexpected "snapping" increasing to over 4" in some instances.

This makes no sense to me, especially since many of the OOTB pipe fittings are smaller than the parts I'm trying to create?  The only way I've been able to work around it is to draw everything much larger than it's actual size, then use dimensions to drive everything down to it's correct size one-by-one, but this is a very tedious process, and it's impossible to add geometry to the model after it's been "driven" down to it's proper size.

To be clear, precise dimensions can be entered, but only if they're over a (seemingly) arbitrary length.

Attached screencast demonstrates the issue in a fresh session of Content Builder using the OOTB template.

http://www.screencast.com/t/yh064Wcb7UM

[nestly2]

Here is a demo showing how it's impossible to place any new point within 4 inches of an existing point.

[nestly2]

I'm going to piggy-back two additional issues I'm having with Content Builder

Problem 2)  When trying use a Sphere or Dome primitive (OOTB or user defined)  into a pipe domain parametric part, the spheres/domes display properly in Content Builder, but are not displayed when the part is inserted.  In addition to the sphere/dome not being displayed, it also seems to interfere with other geometry that the sphere "should" overlap.

Problem 3)  When trying to use an arc as the path for a custom profile (hexagon) the path displays properly in Content builder for both segmented and unsegmented curves, however when the part is inserted, the "unsegmented" curve is not swept along the path, rather it's being drawn as a single segment between the arc start/endpoints.

[Joshua.Benoist]

Hi,

I want to address the first question about drawing objects with dimensions closer than 1.5".  Think of Content Builder as drawing on a sketch pad, not as a drafting table with rulers.  Never draw your initial geometry to a true dimension!

The lines and points do not even have to be straight or form any recognizable shape at all.  So when you want two points that are "EVENTUALLY" going top be 1.5" apart, draw them 12" apart.  Draw everything 12" or more apart.  Forget scale and accuracy.

Once you have lines, points, curves roughed-in or sketched in.  Your next step is to constrain the geometry.  You can take a crooked line and constrain it to the horizontal or vertical, parallel or perpendicular.  Crooked lines become straight.  If they don't, then you have immediate visual feedback that something in your model is broken or over-constrained.  You want that visual feedback.

After applying constraints, then add dimensions but DON'T set the dimension just yet to 1.5".  Your dimensions will show up in the "Model Parameters" list.  You want to use a dimension value that cleans up the line and pulls the overall model into a form that is "proportional" to other lines.  As you add more dimensions, the model should take on the shape and be scaled proportional to the finished model.  This is where your lines or points get "pulled" to a dimension.  AGAIN, you want to see that the lines AND constrained geometry moves to meet your expectations.  If something does not move to meet expectations, then you may need to add a constraint or dimension.  Or delete a constraint if over-constrained.

Once your model stretches and flexes to expectations, plus it should be in the general form of the final skeleton.  You then go to the "Model Parameters" and add in formulas.  Test the formulas to ensure it still flexes to expectations and does not break. 

** That's the whole purpose of having a separate Model Parameters that differ from the Size Parameters.  Model Parameters, are there to assist in flexing the model and roughing in formulas, testing for breaks.  If the model does not change when a dimension value changes, then something is broken or over-constrained.  You WANT the model to be exaggerated in dimensions, so you can see it flex (or break and not flex).  It's part of troubleshooting your model. 

At this point you can extrude, add connectors, etc.  Re-test.

Once you are satisfied with the model, go to the "Size Parameters" where you enter in the Manufacturer's Cut Sheet values.  This is where the 1.5" value should reside.  You can even apply a size range to the model to see that it flexes to those dimensions.

HTH

[Joshua.Benoist]

Problem 2:  Cannot use primitives with fittings.  Primitives are typically used with MvParts.

Problem3:  I have seen similar things break like this in Content Builder.  If confirmed on our end, we will log a change request with development.

JB

[nestly2]

Thank you for the reply Joshua.  I'm not surprised at your response to the 1st problem, because you teach using visual feedback in your demos, however I will point out that in all the content builder videos I've seen, the parts seems to be drawn reasonably close to their actual size, not 20 or 100x larger than the completed part.

If there's a limitation, then I guess I'll deal with it, but I really don't understand why you can't "rough in" the model at something close to it's real world size. If you're suggesting 12 inches as a baseline for the small geometry, then I'll literally have to rough in a 1/2" fitting the size of a dump truck.  Is there a minimum distance, or a calculation to determine how far you have to be from an existing point to prevent pickpoints from snapping to existing geometry/points, because as shown in my examples, the distance seems to be arbitrary.

2) I kinda figured as much, but couldn't find any documentation that says fittings can't contain primatives.  I assume Revolve and Boolean don't work for fittings either since they are "greyed out"

3)  If you can't confirm the problem with arc paths and custom profiles, I'll be happy to provide an example.  Do you have a suggestion how to create a smooth profile as shown in the lower left of the screencap?  The only way I can think of is extruding to multiple profiles on multiple planes?