Trimming problems

[mark.martinezECRPT]

I have Autocad 2023.  I am trying to trim 44 lines using fence.  Only 10 lines trim to the boundaries then the rest get deleted.

Also, if a trim a line that has the boundary out of focus, it deletes the whole line.  I normally do not work in Autocad so I don't know what is going on.

The same is with extend.  If I extend many lines to a boundary using fence, only 10 will extend and the others will extend to the next boundary or not extend at all.

[pendean]

Ensure your AutoCAD commandline is 5-10-20 lines tall, then try those commands again: what is the program reporting is the problem? There is always an alert.

[paullimapa]

Perhaps not all the lines are drawn in same elevation. Maybe first run flatten command and then try trim fence again 

[illusionistNUGXG]

All elements that are used as a cutting line have to be on screen, or else they get ignored and trimming cuts away the whole line (or polyline-segment to the next vertex).

This is done by AutoCAD for performance reasons - otherwise it could take a long time to check all elements of the drawing if they could be cutting lines.

Except - if you start the command TRIM, type C for cutting line*, select all lines (or other objects) you want to trim to,  enter and now you can trim your lines without having the cutting lines on screen.

* i have a german version - here it is S for "Schnittlinie" - i don't know if it is C (for cutting line..or edge?) in english.