The Trim tool in SOLIDWORKS 2019 introduces two new options that will be very useful. It relates to how construction geometry in sketches interact when trimming. Most of the time you want to keep construction geometry so your sketch remains easier to constrain. These construction lines can get in the way especially using the Power Trim option.
- Keep trimmed entities as construction geometry
- Ignore trimming of construction geometry
Let’s take a look at how these options work using the following sketch (all sketch relations hidden for clarity). We have some construction lines and overlapping sketch entities. All of the red arrows represent sketch entities that need to be trimmed away.
Keep trimmed entities as construction geometry
Here is what happens when we use Power trim with ‘Keep trimmed entities to construction geometry‘ DISABLED like it behaved in previous versions. Notice the corner geometry is gone and therefore we lost the dimensions. The original construction lines also got trimmed back to the arc. The sketch is now underdefined.
If we ENABLE the option to ‘Keep trimmed entities to construction geometry‘, dragging across the lines will trim it into separate entities but leave the remnants as construction so it maintains the references. The sketch remains fully defined as the dimensions remain attached to the construction lines.
Ignore trimming of construction geometry
The second option ‘Ignore trimming of construction geometry‘ is very useful when you want to trim several entities but some construction geometry lies in the way. Here’s what would happen if you kept it DISABLED, like previous versions. The inside arc and line need to be trimmed. If you attempt this in one pass you’d have to cross some construction lines.
But now you can ENABLE ‘Ignore trimming of construction geometry‘ so construction geometry is no longer a barrier.