Modifying and developing the Model

One of the main strengths of a parametric modeling system is the ability to develop a model by changing existing features and for that change to propagate though the whole model.

” With great power power comes great responsibility ” – it doesn’t necessarily follow that the model will update successfully, it is your responsibility to build a robust model which considers the implication of changes and development, the power to develop a model can cause references and associativity to fail.

Even with the best planning, features will fall over.  A whole list of features may fail but this is simply a domino effect – if you sort out the first failure it will often resolve the rest of the list.  Make sure you know how to resolve issues, generally this is as simple as redefining sketcher references.

Regeneration

Any change to the model, however small will generally cause the model to be regenerated – rebuilt to consider the implication of the changes.

Use the Regenerate icon in the top toolbar or Ctrl G to manually regenerate a model.  In assemblies you may have to force a regeneration if you have made changes to associated parts to see that change.

 

Double click

Double click a feature in the graphics area to show it’s general parameters.  If the cursor changes to a triangle then an element is draggable.  Click in the background to update the model.

The 3 holes in the above examples reposition themselves along the part as the base extrusion is modified because their position is mathematically controlled by a Relation to stay  equally spaced along its length.

 

Edit Definition

If you cannot dynamically edit a feature in the graphics area or if you want to change fundamental aspects of the feature;

RMB > Edit Definition to re-enter the feature environment and make changes to the feature.

 

Insert Here

Drag the Insert Arrow up the model tree or RMB > Insert Here to insert feature at a specified point in the model tree.  Also use this option to avoid the entire model regenerating with every change.

 

Suppress

RMB feature in Model Tree > Suppress

This doesn’t delete a feature but ‘freezes’ it and takes it out of the build

RMB > Resume to re-activate the feature

Temporarily suppress heavy features such as patterns or groups of fillets to reduce regeneration time.

 

Selection methods

 

 

RMB toggle

There will be occasions when there are multiple entities in one place and the one you want does not highlight;

  • cursor over the entities – don’t move the cursor
  • momentary click RMB rather than press and hold RMB (which gives you RMB menus)
  • toggle to the desired entity – don’t move the cursor
  • LMB to select the entity

Alternatively use the RMB menu option Pick From List;

  • hover over the entity
  • RMB menu (press and hold) > Pick From List
  • select required entity from list

 

Chain of Edges

Edges or curves can be broken down into straight lines, arcs or splines.  These will often need to be individually selected and grouped to create entities such as trajectories or surfaces boundaries – this selection method creates a Chain of Edges

  • Select the anchor curve – you may have to RMB toggle if it is part of a sketched curve.
  • Hold Shift and select chained elements – RMB toggle again if necessary

 

 

 

Dynamic edit Xsec

A useful tip which exploits the Dynamic Edit function is the ability to see a live, draggable cross section of a part (not assembly)

create a datum plane in such a way that it has a dimension with a drag handle – say a simple offset plane through the View Manager, create an xsec using this plane – set the xsec as active

Dynamic Edit the plane and this will dynamically update the cross section